Synthesis via MedWorm.com MedWorm.com provides a medical RSS filtering service. Over 6000 RSS medical sources are combined and output via different filters. This feed contains the latest items from the 'Synthesis' source. Mon, 06 Feb 2012 12:55:20 +0100 A Cost-Effective, Column-Free Route to Ethylene Glycol Oligomers EG6, EG10, and EG12 http://www.medworm.com/index.php?rid=5663903&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289685 SynthesisDOI: 10.1055/s-0031-1289685AbstractAlthough monodisperse ethylene glycol (EG) oligomers are important in a wide range of applications (ranging from drug therapeutics to materials science and engineering), their cost - especially for longer EG oligomers is often prohibitive. For example, decaethylene, EG10, and dodecaethylene, EG12, glycols cost hundreds of dollars per gram, and are only available from most vendors, including Sigma-Aldrich, in the polydispersed form. This high-cost is, in large part, due to laborious nature of synthesis and, above all, purification steps involved. Therefore, the motivation of our work was to design a cost-effective route to the EG oligomers that would altogether avoid the column-chromatography purification. This was achieved by a simple synthetic s... Synthesis journals http://www.medworm.com/rss/comments.php?id=5663903 Fri, 03 Feb 2012 05:00:00 +0100 5663903 One-Pot Synthesis of Dibenzo[b,e][1,4]diazepin-1-ones http://www.medworm.com/index.php?rid=5663902&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289691 SynthesisDOI: 10.1055/s-0031-1289691AbstractA simple and efficient method for the synthesis of wide range of 3,3-dimethyl-11-alkyl or aryl 2,3,4,5-tetrahydro-1H-dibenzo[b,e][1,4]diazepin-1-ones, recently reported as hepatitis C virus (HCV) NS5B polymerase inhibitors, is presented. The proposed method consists of one-pot condensation between 1,2-phenylenediamine and 5,5-dimethylcyclohexane-1,3-dione (dimedone) followed by cyclization with various alkyl and aryl acyl chlorides catalyzed by Er(III) triflate. With respect to methods previously reported, the proposed one-pot procedure furnishes appreciably higher yield of product in shorter reaction time.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Syn... Synthesis journals http://www.medworm.com/rss/comments.php?id=5663902 Fri, 03 Feb 2012 05:00:00 +0100 5663902 Nucleophilic Carbene-Mediated Hydrophosphonylation of Aldimines http://www.medworm.com/index.php?rid=5663901&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289690 SynthesisDOI: 10.1055/s-0031-1289690AbstractAldimines undergo efficient hydrophosphonylation reactions with dimethyl phosphite in the presence of nucleophilic heterocyclic­ carbenes (NHCs) as organocatalysts to give the corresponding (α-aminoalkyl)phosphonates in moderate-to-excellent yields.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5663901 Fri, 03 Feb 2012 05:00:00 +0100 5663901 Efficient and Divergent Synthesis of Functionalized Cyclopropanes via Iodoform Reaction http://www.medworm.com/index.php?rid=5663900&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289693 SynthesisDOI: 10.1055/s-0031-1289693AbstractEfficient and divergent one-pot synthesis of cyclopropyl amides and esters from readily available 1-acetylcyclopropanes via iodoform reaction based on the selection of reaction conditions is reported. A series of substituted cyclopropyl amides were synthesized from 1-acetylcyclopropanes, iodine, and ammonia in water in the presence of K2CO3 in good yields, whereas substituted cyclopropyl esters were obtained from the reaction of 1-acetylcyclopropanes with iodine and alcohols in the presence of DBU.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5663900 Fri, 03 Feb 2012 05:00:00 +0100 5663900 Synthesis of a New Deuterium-Labeled Phytol as a Tool for Biosynthetic Studies http://www.medworm.com/index.php?rid=5663899&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289689 SynthesisDOI: 10.1055/s-0031-1289689AbstractAn efficient and stereoselective synthesis of a new deuterium-labeled phytol as a useful tracer in biosynthetic processes is presented.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5663899 Fri, 03 Feb 2012 05:00:00 +0100 5663899 Decarboxylative Carbon-Carbon Bond-Forming Transformations of (Hetero)aromatic Carboxylic Acids http://www.medworm.com/index.php?rid=5663898&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289686 SynthesisDOI: 10.1055/s-0031-1289686AbstractIn the last decade, the use of (hetero)aromatic carboxylic acids as aryl donors in C-C bond-forming reactions has emerged as a powerful tool for organic synthesis. In this review article we describe the progress that has been achieved in the coupling of these acids with (pseudo)haloarenes, arenes, alkenes and alkynes, among other coupling partners, with particular emphasis on the most recent developments.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5663898 Fri, 03 Feb 2012 05:00:00 +0100 5663898 Synthesis of Chiral Five-, Six-, and Seven-Membered Heterocycles from (S)-3-Hydroxy-γ-butyrolactone http://www.medworm.com/index.php?rid=5643475&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289677 SynthesisDOI: 10.1055/s-0031-1289677AbstractChiral small molecules such as amino alcohols and their heterocyclic derivatives are useful building blocks for asymmetric synthesis and the preparation of biologically active compounds. Using a common starting material derived from carbohydrate, the (S)-3-hydroxy-γ-butyrolactone, we have synthesized several five-, six-, and seven-membered nitrogen-containing chiral heterocycles. These include (S)-3-benzyloxypyrrolidine, a protected 6-substituted morpholin-3-one and its homologous 1,4-oxazepan-3-one, and 6-trityloxymethyl tetrahydro-1,3-oxazine-2-thiones. These chiral small heterocycles were synthesized from the lactone via efficient cyclization reactions. Their syntheses and characterization are reported here.[...]© Georg Thieme Verlag Stuttga... Synthesis journals http://www.medworm.com/rss/comments.php?id=5643475 Mon, 30 Jan 2012 05:00:00 +0100 5643475 Bicyclo[3.2.0]heptane-Based Enamides by Ru/PNNP-Catalyzed Enantioselective Ficini Reactions: Scope and Application in Ligand Design http://www.medworm.com/index.php?rid=5643474&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289679 SynthesisDOI: 10.1055/s-0031-1289679AbstractDouble chloride abstraction from [RuCl2(PNNP)] [PNNP­ = (S,S)-N,N′-bis[o-(diphenylphosphino)benzylidene]cyclohexane-1,2-diamine] gives the elusive dicationic adduct [Ru(OEt)2(PNNP)]²+ which catalyzes the [2+2] cycloaddition of cyclic alkylidene β-keto esters with a variety of ynamides to produce bicyclo[3.2.0]heptane-based enamides with high yields and enan­tioselectivity. The structural features of these products are discussed and selected examples are converted into highly modular diene, phosphite-alkene, and diphosphite derivatives, which were tested as bidentate ligands with Rh(I), Ir(I), and Pd(II).[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: ... Synthesis journals http://www.medworm.com/rss/comments.php?id=5643474 Mon, 30 Jan 2012 05:00:00 +0100 5643474 Asymmetric Synthesis of Functionalized Chromans via a One-Pot Organocatalytic Domino Michael-Hemiacetalization or -Lactonization and Dehydration Sequence http://www.medworm.com/index.php?rid=5643473&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289683 SynthesisDOI: 10.1055/s-0031-1289683AbstractStarting from 2-(nitrovinyl)phenols and various cyclic dicarbonyl nucleophiles, a one-pot thiourea-catalyzed diastereo- and enantioselective synthesis of polyfunctionalized chroman derivatives via a domino Michael-hemiacetalization and dehydration sequence as well as via a domino Michael-lactonization reaction is reported. Cyclopenta[b]chromenes, tricyclic spirochromans, and tetrahydro-1H-xanthenes bearing a variety of functional groups can be synthesized in this way in good to excellent yields (56-91%) and with very good diastereo- (88-99% de) and enantioselectivities (83-99% ee).[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5643473 Mon, 30 Jan 2012 05:00:00 +0100 5643473 A Synthesis of 1,4-Disubstituted Imidazolidin-2-ones from Fused-Ring Aziridines http://www.medworm.com/index.php?rid=5643472&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289684 SynthesisDOI: 10.1055/s-0031-1289684AbstractAs part of an antibacterial drug discovery project, we were interested in preparing bioisosteric replacement analogues of 4,5-disubstituted oxazolidinones. One such isosteric replacement is the imidazolidinone ring system. Here, we report the development of a general synthesis of 1,4-disubstituted imidazolidinones that takes advantage of the base-catalyzed rearrangement of amino­methyl-substituted oxazolidinones.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5643472 Mon, 30 Jan 2012 05:00:00 +0100 5643472 (3,3,5,5-Tetranitropiperidin-1-yl)acetic Acid: Precursor for 1,3,3,5,5-Pentanitropiperidine http://www.medworm.com/index.php?rid=5643471&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289682 SynthesisDOI: 10.1055/s-0031-1289682Abstract(3,3,5,5-Tetranitropiperidin-1-yl)acetic acid is a novel and economical precursor for 1,3,3,5,5-pentanitropiperidine. Treatment of 2,2-dinitropropane-1,3-diol with glycine in water at 65-70 ˚C for five hours gave (3,3,5,5-tetranitropiperidin-1-yl)acetic acid in 52% isolated yield. Nitration of the latter in a mixture of 100% nitric acid and trifluoroacetic anhydride for 12 hours gave 1,3,3,5,5-pentanitropiperidine in essentially quantitative yield. (3,3,5,5-Tetranitropiperidin-1-yl)acetic acid and 1,3,3,5,5-pentanitropiperidine were fully characterized by means of IR and NMR (¹H, ¹³C, and ¹5N) spectroscopy, differential scanning calorimetry, and elemental analysis.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals... Synthesis journals http://www.medworm.com/rss/comments.php?id=5643471 Mon, 30 Jan 2012 05:00:00 +0100 5643471 Catalytic Enantioselective Alkylations with Allylic Alcohols http://www.medworm.com/index.php?rid=5634959&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289681 SynthesisDOI: 10.1055/s-0031-1289681AbstractAllylic alcohols have recently risen to prominence as a valuable synthetic alternative to classic activated alkylating agents in asymmetric catalysis. The intrinsic drawbacks that limited their employment in catalytic enantioselective transformations, until recently, have been efficiently addressed providing elegant solutions. This short review intends to summarize the most salient and recent outcomes in this emerging research area, highlighting the scope and limitations of the most selective catalytic methodologies.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5634959 Thu, 26 Jan 2012 05:00:00 +0100 5634959 Breakthrough in the α-Perchlorination of Acyl Chlorides http://www.medworm.com/index.php?rid=5634957&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289678 SynthesisDOI: 10.1055/s-0031-1289678AbstractThe preparation of α-perchloroacyl chlorides, from reaction of the corresponding unfunctionalized acyl halides with chlorine, was efficiently achieved under base-catalysis, using a tetraalkylammonium chloride as catalyst. The process is solvent-free and the procedure is easy, inexpensive, and suitable for scale-up.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5634957 Thu, 26 Jan 2012 05:00:00 +0100 5634957 An Easy Approach for the Synthesis of N-Substituted Isoindolin-1-ones http://www.medworm.com/index.php?rid=5634956&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289680 SynthesisDOI: 10.1055/s-0031-1289680AbstractA practical and efficient two-step synthesis of N-substituted isoindolin-1-ones was developed. The one-pot reaction of 2-formylbenzoic acid with amines and dimethyl phosphite proceeds in short time either with conventional heating or microwave irradiation under catalyst-free conditions to afford the corresponding N-substituted dimethyl 3-oxoisoindolin-1-ylphosphonates in good yield which, by means of a dephosphonylation reaction with lithium aluminum hydride, give the target N-substituted isoindolin-1-ones in moderate to good yield.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5634956 Thu, 26 Jan 2012 05:00:00 +0100 5634956 Enantioselective Total Synthesis of (+)- and (-)-Vittatalactone http://www.medworm.com/index.php?rid=5634958&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1290155 SynthesisDOI: 10.1055/s-0031-1290155AbstractThe asymmetric total synthesis of both enantiomers of (+)- and (-)-vittatalactone has been achieved using a desymmetrization strategy to create three methyl chiral centers. The key steps in these total syntheses are Myers asymmetric alkylation, copper-­catalyzed alkylation, 2,2,6,6-tetramethyl-1-piperidinyloxyl-(diacet­oxyiodo)benzene [TEMPO-PhI(OAc2)] promoted oxidation and p-toluenesulfonyl chloride mediated lactonization. The products are obtained in good overall yields employing linear synthetic sequences.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5634958 Wed, 25 Jan 2012 05:00:00 +0100 5634958 Scale-Up of Flow-Assisted Synthesis of C2-Symmetric Chiral PyBox Ligands http://www.medworm.com/index.php?rid=5634955&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289676 SynthesisDOI: 10.1055/s-0031-1289676AbstractA series of PyBox ligands were prepared from commercially available chelidonic acid by a multistep flow sequence using mesoreactor technology. A chloro group introduced onto the ligand scaffold was subsequently exploited to give amine derivatives ready for immobilization through microencapsulation technologies.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5634955 Wed, 25 Jan 2012 05:00:00 +0100 5634955 Synform issue 2012/2 http://www.medworm.com/index.php?rid=5624347&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289996 Synthesis 2012; 44: A10-A19DOI: 10.1055/s-0031-1289996© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.Article in Thieme eJournals:Table of contents (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5624347 Mon, 23 Jan 2012 05:00:00 +0100 5624347 A Straightforward Approach towards α-Amino-β-keto Esters via Acylation of Chelated Amino Acid Ester Enolates http://www.medworm.com/index.php?rid=5624346&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289674 SynthesisDOI: 10.1055/s-0031-1289674AbstractChelated enolates were found to be good nucleophiles for reactions with acyl halides affording α-amino-β-keto esters. In most cases, the reactions are over after a few minutes and preparatively useful yields are obtained, independent of the protecting groups and halides used. Besides acyl halides, also the corresponding imidazolides can be used with similar success. With chloroformates as acylating agents different protected amino malonates become accessible.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5624346 Mon, 23 Jan 2012 05:00:00 +0100 5624346 Cyclic Aromatic Analogues of the Hendrickson Reagent; NMR Studies and Electrophilic Properties http://www.medworm.com/index.php?rid=5624345&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289660 Synthesis 2012; 44: e2-e2DOI: 10.1055/s-0031-1289660© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  FREE Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5624345 Mon, 23 Jan 2012 05:00:00 +0100 5624345 Synthesis of a Benzophenone C-Nucleoside as Potential Triplet Energy and Charge Donor in Nucleic Acids http://www.medworm.com/index.php?rid=5624344&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289672 SynthesisDOI: 10.1055/s-0031-1289672AbstractA synthetic route to the C-nucleoside that bears benzophenone as a DNA base substitution directly at the anomeric center of the 2′-deoxyribofuranoside was worked out. Furthermore, the α-anomer of this artificial nucleoside was converted synthetically into the corresponding DNA building block and incorporated into two representative oligonucleotides by automated phosphoramidite chemistry. The chromophore-modified DNA was characterized by methods of optical spectroscopy. The absorption band at ∼350 nm can be used for selective excitation of the benzophenone chromophore outside the nucleic acid absorption range, which makes the benzophenone nucleoside potentially useful for photochemical and photobiological applications.[...]© Georg Thieme Ver... Synthesis journals http://www.medworm.com/rss/comments.php?id=5624344 Mon, 23 Jan 2012 05:00:00 +0100 5624344 Synthesis of Benzoxazines, Quinazolines and 4H-Benzo[e][1,3]thiazine by ANRORC Rearrangements of 1,2,4-Oxadiazoles http://www.medworm.com/index.php?rid=5624343&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289673 SynthesisDOI: 10.1055/s-0031-1289673Abstract1,2,4-Oxadiazoles undergo ANRORC (addition of nucleophile, ring-opening and ring-closure) rearrangements upon reaction with excess of n-butyllithium to give benzoxazines, benzothiazines, and quinazolines in good yields under mild conditions.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5624343 Mon, 23 Jan 2012 05:00:00 +0100 5624343 Microwave-Assisted Synthesis of 1,3-Disubstituted β-Carbolines from α-(Alkylideneamino)nitriles and Gramine http://www.medworm.com/index.php?rid=5624342&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289675 SynthesisDOI: 10.1055/s-0031-1289675AbstractReaction of deprotonated α-(alkylidenamino)nitriles with gramine in the presence of tributylphosphine furnishes α-substituted imines of tryptophane nitrile. Their subsequent intramolecular cyclization followed by dehydrocyanation and oxidation affords 1,3-disubstituted β-carbolines.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5624342 Mon, 23 Jan 2012 05:00:00 +0100 5624342 Transition-Metal-Catalyzed Enantioselective Propargylic Substitution Reactions of Propargylic Alcohol Derivatives with Nucleophiles http://www.medworm.com/index.php?rid=5603498&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1290158 SynthesisDOI: 10.1055/s-0031-1290158AbstractRecent advances in the transition-metal-catalyzed enantioselective propargylic substitution reactions of propargylic alcohol derivatives with nucleophiles are reviewed in this article. After the disclosure of the first example of a ruthenium-catalyzed propargylic alkylation, various types of enantioselective propargylic substitution reactions, including enantioselective propargylation of aromatic compounds, have been reported in the last eight years. In addition, a variety of enantioselective propargylic alkylations use two distinct catalysts, where the two catalysts work cooperatively to promote the asymmetric reactions.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full te... Synthesis journals http://www.medworm.com/rss/comments.php?id=5603498 Mon, 16 Jan 2012 05:00:00 +0100 5603498 Facile Synthesis of Substituted 1,1-Difluoroallenes via Carbonyl Difluorovinylidenation http://www.medworm.com/index.php?rid=5603497&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1290157 SynthesisDOI: 10.1055/s-0031-1290157AbstractTwo methods for the difluorovinylidenation of carbonyl compounds have been developed to synthesize 1,1-difluoroallenes bearing various substituents. The reaction of 1-bromo-2,2-difluorovinyllithium, generated from 1,1-dibromo-2,2-difluoroethylene and n-butyllithium, with aldehydes or ketones, and subsequent acetylation, gives 2-bromo-3,3-difluoroallylic acetates. Elimination of these acetates with n-butyllithium affords 1,1-difluoroallenes in high yield. 3,3-Difluoro-2-iodoallylic acetates are similarly prepared from aldehydes or ketones on treatment with 2,2-difluoro-1-iodovinyllithium, generated from 1,1,1-trifluoro-2-iodoethane and lithium diisopropylamide, followed by acetylation. These acetates readily undergo elimination with zinc metal to ... Synthesis journals http://www.medworm.com/rss/comments.php?id=5603497 Mon, 16 Jan 2012 05:00:00 +0100 5603497 Efficient Palladium-Catalyzed Cross-Coupling Reaction of Alkynyl Halides with Organoboronic Acids under Aerobic Conditions http://www.medworm.com/index.php?rid=5603496&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1290159 SynthesisDOI: 10.1055/s-0031-1290159AbstractLigand-free palladium-catalyzed cross-coupling reaction of alkynyl halides with organoboronic acids under aerobic conditions has been developed. In the presence of bis(dibenzylideneacetone)palladium(0) and cesium carbonate, a variety of alkynyl halides (I, Br, and Cl) underwent the Suzuki-Miyaura cross-­coupling reaction with organoboronic acids at room temperature to afford the corresponding unsymmetrical diarylalkynes in moderate to good yields. It is noteworthy that this is first report on the reaction of alkynyl chlorides with arylboronic acids.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5603496 Mon, 16 Jan 2012 05:00:00 +0100 5603496 Expeditious Synthesis of Papilionaceous Molecules Containing Oligobenzofurans http://www.medworm.com/index.php?rid=5603495&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1290066 SynthesisDOI: 10.1055/s-0031-1290066AbstractAn efficient synthetic route to construct particular papilionaceous molecules containing oligobenzofurans is described. The key steps involved composing the backbone of the molecules by the Sonogashira cross-coupling reaction, followed by closing the benzofuran ring under alkaline conditions, and further aromatic cyclization of a multi-benzofuranyl precursor using ferric chloride as the oxidative reagent. Basic optical studies (UV-Vis, fluorescence, and fluorescence quantum yield) have been carried out on the synthesized molecules.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5603495 Mon, 16 Jan 2012 05:00:00 +0100 5603495 Stereoselective Synthesis of (4S,6S)-6-Hydroxy-4-undecanolide: A Pheromone of the Giant White Butterfly Idea leuconoe http://www.medworm.com/index.php?rid=5603494&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289671 SynthesisDOI: 10.1055/s-0031-1289671AbstractThe stereoselective synthesis of (4S,6S)-6-hydroxy-4-undecanolide, a major pheromone component in the secretion of Idea leuconoe has been accomplished employing Prins cyclization to produce anti-1,3-diols and hydroboration/oxidation of terminal olefin to introduce primary alcohol as the key steps.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5603494 Mon, 16 Jan 2012 05:00:00 +0100 5603494 Second-Generation Synthesis of (-)-Viriditoxin http://www.medworm.com/index.php?rid=5603493&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289651 SynthesisDOI: 10.1055/s-0031-1289651AbstractViriditoxin is a secondary metabolite isolated from Aspergillus­ viridinutans that has been shown to inhibit FtsZ, the bacterial homologue of eukaryotic tubulin. A streamlined, scalable, and highly diastereoselective synthesis of this complex natural product is described. Key advances include a more efficient synthesis of the requisite unsaturated pyranone, scalable assembly of the naphthopyranone monomer, and improved diastereoselectivity in the biaryl-coupling reaction. In addition, we disclose a serendipitous ruthenium-catalyzed anion dimerization resulting from trace metal left by an RCM reaction.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesi... Synthesis journals http://www.medworm.com/rss/comments.php?id=5603493 Mon, 16 Jan 2012 05:00:00 +0100 5603493 Specific Polar Solvents as Organocatalysts for the Hydrosilylation of Isoprene http://www.medworm.com/index.php?rid=5603492&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289669 SynthesisDOI: 10.1055/s-0031-1289669AbstractIsoprene was hydrosilylated in the absence of transition metals by using specific organic solvents as both reaction media and organocatalysts. A highly selective reaction with successful catalyst recycling could be performed by using propylene carbonate as the reaction medium.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5603492 Mon, 16 Jan 2012 05:00:00 +0100 5603492 Stereoselective Total Synthesis of Putaminoxin http://www.medworm.com/index.php?rid=5603491&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1290156 SynthesisDOI: 10.1055/s-0031-1290156AbstractThe stereoselective total synthesis of a phytotoxic macrolide putaminoxin, isolated from the culture of Phoma putaminum fungus, has been accomplished by utilization of Sharpless asymmetric epoxidation, Birch reduction, Jacobsen’s kinetic resolution of racemic epoxide, and Yamaguchi lactonization as key transformations.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5603491 Mon, 16 Jan 2012 05:00:00 +0100 5603491 Recent Developments in Palladium-Catalyzed Alkene Aminoarylation Reactions for the Synthesis of Nitrogen Heterocycles http://www.medworm.com/index.php?rid=5603490&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289668 SynthesisDOI: 10.1055/s-0031-1289668AbstractThis short review describes new developments in palladium-catalyzed aminoarylation reactions between aryl halides and alkenes bearing pendant nitrogen nucleophiles. These transformations provide a novel and powerful method for accessing numerous three-, five-, six-, and seven-membered nitrogen heterocycles.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5603490 Mon, 16 Jan 2012 05:00:00 +0100 5603490 Stereodivergent Synthesis of the C1-C9 Tetrahydropyran Subunit of Zincophorin and Isomers Thereof http://www.medworm.com/index.php?rid=5603489&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289661 SynthesisDOI: 10.1055/s-0031-1289661AbstractZincophorin C1-C9 fragment and seven tetrahydropyran analogues were prepared diastereoselectively by sequential iodo­etherification and radical hydrogen-transfer reactions. Stereoselective formation of 3,7-trans or 3,7-cis rings was rationalized through minimization of allylic-1,3 strain in chair-like transition states. Subsequent hydrogen-transfer provided 7,8-anti or 7,8-syn isomers under acyclic stereocontrol or endocyclic control respectively. The latter approach relies on the formation of a [4.4.0] bicyclic complexes resulting from the chelation of the oxygen of the tetrahydropyran ring and the ester by a bidentate Lewis acid.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |... Synthesis journals http://www.medworm.com/rss/comments.php?id=5603489 Mon, 16 Jan 2012 05:00:00 +0100 5603489 Rapid Synthesis of Benzodiazepines by Ring Expansion of Aziridines with Anthranilic Acids by Using a Grinding Technique http://www.medworm.com/index.php?rid=5603488&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289670 SynthesisDOI: 10.1055/s-0031-1289670AbstractA grinding-induced, atom-economic, rapid, efficient, one-pot protocol was developed for the synthesis of pharmaceutically relevant benzo-1,4-diazepin-5-ones in excellent yields (72-91%) and high regioselectivities. The method involves a ring-opening­-ring-closure cascade of aziridines with anthranilic acids by grinding the neat reactants at room temperature in the presence of lithium bromide as a mild catalyst. Among the advantages of this protocol are its economic viability, the ability to recycle the catalyst, and the formation of water as the only byproduct.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5603488 Mon, 16 Jan 2012 05:00:00 +0100 5603488 The Synthesis of Highly Basic Ï€-Extended Porphyrins by Palladium-Catalyzed Amination http://www.medworm.com/index.php?rid=5568258&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289667 SynthesisDOI: 10.1055/s-0031-1289667AbstractRecently synthesized tetrabenzoporphyrins and tetra­naphthoporphyrins with extended Ï€-systems and bearing 4-bromo­phenyl substituents were subjected to palladium-catalyzed amination by primary and secondary amines. The yields of the tetra­amino derivatives were markedly dependent on the nature of amine reactant.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5568258 Wed, 04 Jan 2012 05:00:00 +0100 5568258 A Facile Multicomponent Reaction Involving Isoquinoline, Dimethyl Allenedicarboxylate, and 2-Oxo-1H-indol-3-ylidenes http://www.medworm.com/index.php?rid=5568255&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289666 SynthesisDOI: 10.1055/s-0031-1289666AbstractTransient zwitterions generated from dimethyl allenedicarboxylate and isoquinoline were successfully intercepted with 2-oxo-1H-indol-3-ylidenes to result in a facile multicomponent reaction under mild conditions.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5568255 Wed, 04 Jan 2012 05:00:00 +0100 5568255 Rhodium-Catalyzed [2+2+2] Cycloaddition of Alkynes for the Synthesis of Substituted Benzenes: Catalysts, Reaction Scope, and Synthetic Applications http://www.medworm.com/index.php?rid=5568261&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289665 SynthesisDOI: 10.1055/s-0031-1289665AbstractThe transition-metal-catalyzed [2+2+2] cycloaddition of alkynes is a useful and atom-economical method for the synthesis of substituted benzenes. This comprehensive review covers the [2+2+2]-cycloaddition reactions catalyzed by rhodium complexes. Applications of the rhodium-catalyzed [2+2+2] cycloaddition in the synthesis of functional organic compounds are also described.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5568261 Tue, 03 Jan 2012 05:00:00 +0100 5568261 Highly Efficient and Broad-Scope Protocol for the Preparation of 7-Substituted 6-Halopurines via N9-Boc-Protected 7,8-Dihydropurines http://www.medworm.com/index.php?rid=5568259&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1290068 SynthesisDOI: 10.1055/s-0031-1290068Abstract9-Boc-6-chloropurine, which can be obtained in high yield, is nearly quantitatively reduced with the THFË™BH3 complex. The obtained 9-Boc-7,8-dihydropurine derivative is more stable compared to the corresponding 9-tritylpurine and can be smoothly N7-alkylated, acylated, or it can serve as an N-nucleophile in conjugate additions. Deprotection with trifluoroacetic acid followed by MnO2 oxidation affords the N7-substituted purines in high yields. The whole sequence of alkylation, deprotection, and oxidation can be done with crude intermediates using chromatography only for the purification of the final N7-substituted purine.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full te... Synthesis journals http://www.medworm.com/rss/comments.php?id=5568259 Tue, 03 Jan 2012 05:00:00 +0100 5568259 Heck Arylation of Styrenes Promoted by an Air-Stable Phosphinito Complex with Palladium(II); Synthesis of Resveratrol http://www.medworm.com/index.php?rid=5568257&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289664 SynthesisDOI: 10.1055/s-0031-1289664AbstractAn air-stable phosphinito complex of palladium(II) was found to be an efficient catalyst in the Heck reaction of a variety of aryl halides and styrenes. Resveratrol was concisely synthesized in 63% overall yield; the reactions were performed under conventional and microwave heating.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5568257 Tue, 03 Jan 2012 05:00:00 +0100 5568257 Stereoselective Synthesis of (Z)-1,2-Dithio-1-alkenes via Copper-Catalyzed Thiolation of (Z)-2-Bromovinyl Sulfides http://www.medworm.com/index.php?rid=5568256&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1290067 We describe a new method for the stereoselective synthesis of (Z)-1,2-dithio-1-alkenes via copper-catalyzed cross-coupling of (Z)-2-bromovinyl sulfides and thiols. The desired products are obtained in good to excellent yields. The double bond geometry of the starting (Z)-2-bromovinyl sulfides is retained under these reaction conditions.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5568256 Tue, 03 Jan 2012 05:00:00 +0100 5568256 Synthesis of (3R,3′R)-Zeaxanthin and Its meso-Stereoisomer from (3R,3′R,6′R)-Lutein via (3R)-3′,4′-Anhydrolutein http://www.medworm.com/index.php?rid=5568262&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289662 SynthesisDOI: 10.1055/s-0031-1289662AbstractA process has been developed for the partial synthesis of (3R,3′R)-zeaxanthin and (3R,3′S; meso)-zeaxanthin from commercially available (3R,3′R,6′R)-lutein. This involves the regioselective hydroboration of a dehydration product of lutein, namely (3R)-3′,4′-didehydro-β,β-caroten-3-ol [(3R)-3′,4′-anhydrolutein], to yield a mixture of (3R,3′R)-zeaxanthin and (3R,3′S; meso)-zeaxanthin followed­ by separation of these carotenoids by enzyme-mediated acylation. (3R,3′R,6′R)-Lutein, (3R,3′R)-zeaxanthin and its meso-isomer accumulate in human ocular tissues and have been implicated in the prevention of age-related macular degeneration (AMD).[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of ... Synthesis journals http://www.medworm.com/rss/comments.php?id=5568262 Mon, 02 Jan 2012 05:00:00 +0100 5568262 Friedel-Crafts 3-(2-Bromobenzoylation) of Indoles and Intramolecular Direct Arylation: An Efficient Route to Indenoindolones http://www.medworm.com/index.php?rid=5568260&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289663 SynthesisDOI: 10.1055/s-0031-1289663AbstractAn efficient two-step approach, comprising the Friedel-Crafts reaction of 2-bromobenzoyl chlorides with indoles to give 3-(2-bromobenzoyl)indoles and their palladium-catalyzed intramolecular direct arylation to give indenoindolones, has been developed. 3-(2-Bromobenzoyl)indoles were crucial intermediates; the method was successful with N-unprotected or N-protected indoles. This approach affords a convenient preparation of diverse substituted and functionalized indenoindolones in good to high yields from easily accessible starting materials. Several moieties, which are commonly integrated into bioactive compounds, can be incorporated with ease by this synthesis.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of c... Synthesis journals http://www.medworm.com/rss/comments.php?id=5568260 Mon, 02 Jan 2012 05:00:00 +0100 5568260 Synthesis of Allyl Acetates via Palladium-Catalysed Functionalisation of Allenes and 1,3-Dienes http://www.medworm.com/index.php?rid=5556582&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289658 SynthesisDOI: 10.1055/s-0031-1289658AbstractÏ€-Allylpalladium intermediates are known to participate efficiently in transformations involving nucleophilic species. Exploring these processes, we have developed a method for the preparation of allyl acetates via palladium-catalysed functionalisation of allenes and 1,3-dienes. Reactions of aryl iodides with either of these two classes of compounds and excess sodium acetate in the presence of Pd(OAc)2 and Ph3P as the catalytic system afforded the respective allyl acetates in moderate to good yields. The scope of this process has been investigated. The described method is an addition to the synthetic repertoire for the preparation of allyl acetates, and may be useful, in particular, for the synthesis of structurally complex compounds of this typ... Synthesis journals http://www.medworm.com/rss/comments.php?id=5556582 Thu, 29 Dec 2011 05:00:00 +0100 5556582 One-Pot Ester Synthesis from Allyl and Benzyl Halides and Alcohols by Palladium-Catalyzed Carbonylation http://www.medworm.com/index.php?rid=5556581&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289659 SynthesisDOI: 10.1055/s-0031-1289659AbstractA mild and efficient one-pot synthesis of esters based on the Pd-catalyzed alkoxy- and aryloxycarbonylation of allylic and benzylic halides is described. The methodology has been applied to primary, secondary, and tertiary alcohols as well as to phenol derivatives. The O-protection of some biologically relevant molecules is also reported.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5556581 Thu, 29 Dec 2011 05:00:00 +0100 5556581 Synthesis of Quinolines via Friedländer Reaction in Water and under Catalyst-Free Conditions http://www.medworm.com/index.php?rid=5542039&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289657 SynthesisDOI: 10.1055/s-0031-1289657AbstractA straightforward and efficient method for the synthesis of quinolines via Friedländer reaction of 2-aminobenzaldehyde with various ketones or malononitrile in water without using any catalyst at 70 ËšC is reported.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5542039 Fri, 23 Dec 2011 05:00:00 +0100 5542039 Three-Component Reaction between Vinyl Ethers, Secondary Phosphines, and Elemental Selenium: One-Pot Synthesis of 1-(Alkoxy)ethyl and 1-(Aryloxy)ethyl Phosphinodiselenoates http://www.medworm.com/index.php?rid=5542038&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289655 SynthesisDOI: 10.1055/s-0031-1289655AbstractA family of previously unknown phosphinodiselenoic esters containing a selenoacetal moiety, R²2P(=Se)SeCH(Me)OR¹ (R¹, R² = alkyl, aryl, etc.), were synthesized by means of a three-component reaction between the elemental selenium and the corresponding vinyl ether and secondary phosphine. The reaction proceeds readily in 1,4-dioxane at 90 ˚C for 1-1.5 hours and gives the phosphinodiselenoic esters quantitatively and in an entirely atom-economic manner. The reaction proceeds through electrophilic addition to the electron-rich double bond of the phosphinodiselenoic acids generated in situ.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5542038 Fri, 23 Dec 2011 05:00:00 +0100 5542038 Cyclic Aromatic Analogues of the Hendrickson Reagent; NMR Studies and Electrophilic Properties http://www.medworm.com/index.php?rid=5532625&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289998 SynthesisDOI: 10.1055/s-0031-1289998AbstractTwo novel cyclic aromatic analogues of the Hendrickson ‘POP’ reagent, 1,1,3,3-tetraphenyl-1,3-dihydro-2,1,3-benzoxadi­phosphole-1,3-diium bis(trifluoromethanesulfinate) and bis(tri­fluoromethanesulfonate), have been readily prepared by the treatment of 1,2-bis(diphenylphosphino)benzene or 1,2-bis(diphenyl­phosphoryl)benzene, respectively, with trifluoromethanesulfonic anhydride in dichloromethane. ³¹P and ¹9F NMR studies indicated that while the latter complex is formed as the sole product, the former species was shown to be the predominant component in equilibrium with 1-(diphenylphosphino)-2-[diphenyl(trifluorometh­ylsulfonyloxy)phosphonio]benzene trifluoromethanesulfinate and 1,2-bis[diphenyl(trifluoromethylsulfonyloxy)phosphonio]be... Synthesis journals http://www.medworm.com/rss/comments.php?id=5532625 Thu, 22 Dec 2011 05:00:00 +0100 5532625 First Synthesis of Benzopyridoiodolium Salts and Twofold Buchwald-Hartwig Amination for the Total Synthesis of Quindoline http://www.medworm.com/index.php?rid=5532624&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289652 SynthesisDOI: 10.1055/s-0031-1289652AbstractThe first synthesis of cyclic benzopyridoiodolium salts is described. These hypervalent iodine intermediates are used in an efficient strategy for the construction of the δ-carboline core. This novel approach involves a twofold palladium-catalyzed Buchwald-Hartwig reaction between these unprecedented reagents and a primary amine. Our methodology successfully provides the expected N-substituted δ-carboline core and is efficiently applied in the total synthesis of quindoline.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5532624 Thu, 22 Dec 2011 05:00:00 +0100 5532624 Synthesis of Tetrasubstituted NH Pyrroles and Polysubstituted Furans via an Addition and Cyclization Strategy http://www.medworm.com/index.php?rid=5532622&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289993 SynthesisDOI: 10.1055/s-0031-1289993AbstractThe FeCl3-catalyzed addition and cyclization of enamino esters with nitroolefins provides a straightforward and general method for the synthesis of tetrasubstituted NH pyrroles. This novel method tolerates a wide range of functionality, and allows for rapid elaboration of the nitroolefins into a variety of substituted pyrroles in good yields. Further, an efficient KOAc-promoted addition and cyclization protocol toward substituted furans has been described as well.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5532622 Thu, 22 Dec 2011 05:00:00 +0100 5532622 A Practical Synthesis of Cefcapene Pivoxil http://www.medworm.com/index.php?rid=5532621&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289654 SynthesisDOI: 10.1055/s-0031-1289654AbstractCefcapene pivoxil monohydrochloride monohydrate, a broad spectrum third-generation cephalosporin for oral administration, was prepared by reacting three centers of 7β-amino-3-(hydroxymethyl)cephalosporinic acid (7-HACA), derived from 7β-aminocephalosporanic acid. The coupling of 7-HACA and (Z)-2-[2-(Boc-amino)thiazol-4-yl]pent-2-enoic acid, followed by carbamylation with chlorosulfonyl isocyanate, and precipitation with diisopropylamine gave the key intermediate, in which thiazole side chain and carbamoyl group had been introduced into the 7-amino and 3-hydroxymethyl groups of 7-HACA, respectively, in a continuous procedure. Afterwards, the intermediate was esterified with pivaloyloxymethyl iodide to complete the modification of the C4 carboxy ... Synthesis journals http://www.medworm.com/rss/comments.php?id=5532621 Thu, 22 Dec 2011 05:00:00 +0100 5532621 Synthetic Approaches to Highly Functional β-Carboline Building Blocks via Allylic Amidation http://www.medworm.com/index.php?rid=5532619&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289656 SynthesisDOI: 10.1055/s-0031-1289656AbstractA new, straightforward synthesis of highly functional β-carboline building blocks is presented that makes use of allylic amidation methodology. The products obtained carry a terminal double bond as well as an easy-to-deprotect amide, which make them perfectly suitable for further functionalization. The use of the trifluoroacetamide group is exploited in a dual fashion; it acts as a protecting group and functions as the nucleophile for the allylic amidation reaction.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5532619 Thu, 22 Dec 2011 05:00:00 +0100 5532619 A Thiophosphoryl Chloride Assisted Transformation of Arylaldoximes to Thioamides http://www.medworm.com/index.php?rid=5532618&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289994 SynthesisDOI: 10.1055/s-0031-1289994AbstractPrimary benzothioamides were accessed from benzaldoximes (benzaldehyde oximes) via benzonitriles in a sequential tandem approach utilizing thiophosphoryl chloride as a dehydrating and thionating agent.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5532618 Thu, 22 Dec 2011 05:00:00 +0100 5532618 Diastereo- and Enantioselective Synthesis of Fluorinated Proline Derivatives via Copper(I)-Catalyzed Asymmetric 1,3-Dipolar Cycloaddition http://www.medworm.com/index.php?rid=5532615&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289653 SynthesisDOI: 10.1055/s-0031-1289653AbstractA catalytic asymmetric cycloaddition reaction of fluoromethyl-substituted nitroalkenes with azomethine ylides was developed using a catalyst derived from copper(I) perchlorate and a commercially available, chiral Walphos ligand. This method provides a simple approach to optically active exo-3-(fluoromethyl)proline derivatives in high yields, as well as in high diastereo- and enantioselectivities.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5532615 Thu, 22 Dec 2011 05:00:00 +0100 5532615 Synform issue 2012/1 http://www.medworm.com/index.php?rid=5532623&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289951 Synthesis 2012; 44: A1-A9DOI: 10.1055/s-0031-1289951© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.Article in Thieme eJournals:Table of contents (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5532623 Wed, 21 Dec 2011 05:00:00 +0100 5532623 Synthesis of 1-Chloroalkynes from Alkynylsilanes Using Trichloroisocyanuric Acid as Chlorinating Agent http://www.medworm.com/index.php?rid=5532617&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289642 Synthesis 2012; 44: 0158-0158DOI: 10.1055/s-0031-1289642© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  FREE Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5532617 Wed, 21 Dec 2011 05:00:00 +0100 5532617 tert-Butoxide-Assisted Amidation of Esters under Green Conditions http://www.medworm.com/index.php?rid=5532616&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289625 Synthesis 2012; 44: e1-e1DOI: 10.1055/s-0031-1289625© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  FREE Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5532616 Wed, 21 Dec 2011 05:00:00 +0100 5532616 CAN-Catalyzed Regioselective Synthesis of Pyrido[2,3-c]carbazoles by the Povarov Reaction http://www.medworm.com/index.php?rid=5532626&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289967 SynthesisDOI: 10.1055/s-0031-1289967AbstractA simple route for the synthesis of 3-methyl-3H-pyrido[2,3-c]carbazoles via Povarov reaction of 3-aminocarbazoles, and ethyl vinyl ether is described. This transformation, catalyzed by cerium(IV) ammonium nitrate (CAN) under mild reaction conditions, provides the pyrido[2,3-c]carbazoles in good yields with high regioselectivity.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5532626 Tue, 20 Dec 2011 05:00:00 +0100 5532626 Highly Efficient and Enantioselective α-Arylation of Cycloalkanones by Scandium-Catalyzed Diazoalkane-Carbonyl Homologation http://www.medworm.com/index.php?rid=5532620&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289650 SynthesisDOI: 10.1055/s-0031-1289650AbstractFunctionalized α-tertiary and -quaternary 2-arylcycloalkanones are rapidly accessed by scandium(III) triflate-catalyzed diazo­alkane-carbonyl homologations. Recent developments have allowed for carbon insertion reactions to be performed with catalyst loadings as low as 0.5 mol% on scales up to 5 mmol. Pairing readily available bis- and tris(oxazoline) based ligands with scandium triflate allows access to arylated medium ring carbocycles with enantioselectivities up to 98:2 er and >98% yield. The formal C-C insertion of aryldiazo­methanes into unsubstituted cycloalkanones provides a single-step solution to the ongoing challenge of α-arylation.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |... Synthesis journals http://www.medworm.com/rss/comments.php?id=5532620 Tue, 20 Dec 2011 05:00:00 +0100 5532620 An Efficient and Practical Synthesis of Aryl and Hetaryl α-Keto Esters http://www.medworm.com/index.php?rid=5511819&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289647 SynthesisDOI: 10.1055/s-0031-1289647AbstractA general and highly efficient method was developed for the synthesis of α-keto esters by oxidative esterification of 2,2-dibromo-1-(het)arylethanones by sequential treatment with dimethyl sulfoxide and an alkanol. The versatility of the reaction was established by synthesizing a range of α-keto esters by treatment of 2,2-dibromoethanones, derived from aryl or hetaryl ketones, with di­methyl sulfoxide and a cyclic or acyclic primary or secondary alcohol. The mechanism of the reaction was established by means of a detailed study.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5511819 Fri, 16 Dec 2011 05:00:00 +0100 5511819 Parallel Synthesis of Aminobenzimidazole-Tethered Thiazoles http://www.medworm.com/index.php?rid=5511826&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289644 SynthesisDOI: 10.1055/s-0031-1289644AbstractA multistep approach to construct thiazole-derived aminobenzimidazoles from commercially available amino acids, amines, carboxylic acids, and α-halo ketones is described. Coupling of 9-fluorenylmethoxycarbonyl-protected (Fmoc-protected) amino acids to resin-bound aminobenzimidazoles provides essential intermediates for the construction of an array of thiazoles by utilizing the Hantzsch cyclization strategy. The aminobenzimidazole-tethered thiazoles were isolated in moderate yields.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5511826 Thu, 15 Dec 2011 05:00:00 +0100 5511826 First Stereoselective Total Synthesis of Naturally Occurring (6R)-6-(4-Oxopentyl)-5,6-dihydro-2H-pyran-2-one and Its (6S)-Enantiomer¹ http://www.medworm.com/index.php?rid=5511825&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289643 SynthesisDOI: 10.1055/s-0031-1289643Abstract(6R)-6-(4-Oxopentyl)-5,6-dihydro-2H-pyran-2-one, a naturally occurring α,β-unsaturated δ-lactone, and its (6S)-enan­tiomer have been synthesized stereoselectively starting from pentane-1,5-diol. The synthesis involves Maruoka asymmetric allylation and ring-closing metathesis as the key steps.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5511825 Thu, 15 Dec 2011 05:00:00 +0100 5511825 A Concise and Diastereoselective Synthesis of Piperidine and Indolizidine Alkaloids via Aza-Prins Cyclization http://www.medworm.com/index.php?rid=5511824&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289648 SynthesisDOI: 10.1055/s-0031-1289648AbstractThe synthesis of 2-substituted and 2,4-disubstituted piperidine alkaloids such as (±)-coniine, (±)-hydroxypipecolic acid, (±)-pipecolic acid, (±)-coniceine, and (±)-4-hydroxy-2-hydroxy­methyl piperidine have been accomplished in a highly diastereo­selective manner by employing aza-Prins cyclization as a key step to construct the piperidine core of these alkaloids.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5511824 Thu, 15 Dec 2011 05:00:00 +0100 5511824 Isocyanide-Based Four-Component Synthesis of Benzo[a]pyrano[2,3-c]phenazines http://www.medworm.com/index.php?rid=5511823&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289968 SynthesisDOI: 10.1055/s-0031-1289968AbstractAn efficient and simple method for the synthesis of biologically interesting benzo[a]pyrano[2,3-c]phenazines by a four-component reaction of o-phenylenediamines, 2-hydroxynaphthalene-1,4-dione, isocyanides, and dialkyl acetylenedicarboxylates in N,N-dimethylformamide at 100 ËšC is reported.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5511823 Thu, 15 Dec 2011 05:00:00 +0100 5511823 Synthesis of Functionalized 3,4-Diarylbenzophenones and 2,4-Diarylbenzophenones by Site-Selective Suzuki and Sonogashira Cross-Coupling Reactions of Bis(triflates) of 3,4- and 2,4-Dihydroxybenzophenone http://www.medworm.com/index.php?rid=5511820&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289649 SynthesisDOI: 10.1055/s-0031-1289649AbstractPalladium(0)-catalyzed Suzuki and Sonogashira cross-coupling reactions of the bis(triflates) of 2,4- and 3,4-dihydroxybenzophenone afforded 2,4- and 3,4-diarylbenzophenones, respectively. The reactions proceeded with very good site-selectivity in favor of position 4.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5511820 Thu, 15 Dec 2011 05:00:00 +0100 5511820 First Enantioselective Synthesis of Aptazepine http://www.medworm.com/index.php?rid=5511822&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289646 SynthesisDOI: 10.1055/s-0031-1289646AbstractAptazepine (2-methyl-1,3,4,14b-tetrahydro-2H,10H-pyrazino[1,2-a]pyrrolo[2,1-c][1,4]benzodiazepine), a potent tetracyclic antidepressant, was synthesized in both its enantiopure forms by using an asymmetric transfer hydrogenation in a key step. Reduction of the prochiral imine 7 gave the products (R)- and (S)-8 in 63% and 61% ee, respectively, but a single crystallization improved the enantiomeric purity to 98% ee. The final (R)- and (S)-aptazepines were prepared in four subsequent steps. The absolute configuration of intermediate (S)-8 was determined by X-ray crystallography.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5511822 Wed, 14 Dec 2011 05:00:00 +0100 5511822 A Stereodivergent Route to Four Stereoisomeric 3′-Acetoxycyclopentenylglycine Derivatives http://www.medworm.com/index.php?rid=5511821&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289645 SynthesisDOI: 10.1055/s-0031-1289645AbstractA short and efficient synthetic route to four stereoisomeric 3′-acetoxycyclopentenylglycine derivatives from l-serine has been developed. The method features a stereoselective conjugate addition and ring-closing metathesis as key steps.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5511821 Wed, 14 Dec 2011 05:00:00 +0100 5511821 Stereoselective Concise Total Synthesis of Leodomycin C and D http://www.medworm.com/index.php?rid=5492265&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289640 SynthesisDOI: 10.1055/s-0031-1289640AbstractStereoselective concise total synthesis of leodomycin C and D from commercially available propylene oxide using Jacobsen’s hydrolytic kinetic resolution (HKR), base-promoted alkyne zipper reaction, TPP-promoted enyne ester (ynoate) to diene ester (dienoate) isomerization, and (R)-(+)-2-methyl-CBS-oxazaborolidine reduction as key steps is reported.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5492265 Thu, 08 Dec 2011 05:00:00 +0100 5492265 The Heck Reaction of Allylic Alcohols Catalysed by an Air-Stable Phosphinito Complex of Palladium(II) http://www.medworm.com/index.php?rid=5492264&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289639 SynthesisDOI: 10.1055/s-0031-1289639AbstractThe Heck coupling of aryl bromides with primary and secondary allylic alcohols, performed in the presence of an air-stable­ phosphinito complex of palladium(II), produced the corresponding carbonyl compounds. Reactions with tertiary allylic alcohols under the same conditions generated the aromatic conjugated alcohols.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5492264 Thu, 08 Dec 2011 05:00:00 +0100 5492264 Microwave-Assisted Solvent-Free Diels-Alder Reaction - A Fast and Simple Route to Various 5,6-Substituted Norbornenes and Polychlorinated Norbornenes http://www.medworm.com/index.php?rid=5482567&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289624 Synthesis 2011; 2011: e4-e4DOI: 10.1055/s-0031-1289624© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  FREE Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5482567 Tue, 06 Dec 2011 05:00:00 +0100 5482567 A Facile One-Pot Synthesis of Substituted Thieno[2,3-b]pyridines from Enaminones http://www.medworm.com/index.php?rid=5482568&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289633 SynthesisDOI: 10.1055/s-0031-1289633AbstractA facile and efficient one-pot synthesis of substituted thieno[2,3-b]pyridines has been developed. Treatment of enamin­ones, such as 2-acetyl-3-(dimethylamino)propenamides and -propenoates, with 2-cyanothioacetamide in the presence of potassium carbonate in N,N-dimethylformamide at 80 ËšC followed by addition of methylene-active bromides at room temperature provided, via intramolecular cyclization, 2,3,5,6-tetrasubstituted thieno[2,3-b]pyridines in yields of 78-90%. This protocol, which combines construction and modification of the thieno[2,3-b]pyridine ring, increases the structural diversity of the final products from readily available materials.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |... Synthesis journals http://www.medworm.com/rss/comments.php?id=5482568 Mon, 05 Dec 2011 05:00:00 +0100 5482568 Synthesis of Carbo- and Heterocycles via Coupling-Isomerization Reactions http://www.medworm.com/index.php?rid=5482566&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289636 SynthesisDOI: 10.1055/s-0031-1289636AbstractThe coupling-isomerization reaction is an unusual outcome of the Sonogashira coupling of propargyl alcohols, N-tosyl­amines, or ethers with preferentially electron-deficient (hetero)aryl halides. As a result, chalcones, enimines and allenyl ethers are generated in situ. The former two are readily transformed into heterocycles in consecutive cyclization and cyclocondensations in a one-pot fashion, whereas the latter are excellent entries into pericyclic domino processes for the rapid construction of complex polycyclic scaffolds.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5482566 Mon, 05 Dec 2011 05:00:00 +0100 5482566 An Efficient and Convenient Bromination of BODIPY Derivatives with Copper(II) Bromide http://www.medworm.com/index.php?rid=5482565&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289637 SynthesisDOI: 10.1055/s-0031-1289637AbstractEfficient and convenient methods for the mono- and dibromination of 1,3,5,7-tetramethyl-substituted BODIPYs were developed by using copper(II) bromide as the bromination reagent under mild reactions, in good to excellent yields. The selectivity of mono- or dibromination depends strongly on the additives of the reactions.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5482565 Mon, 05 Dec 2011 05:00:00 +0100 5482565 Selective Copper- or Silver-Catalyzed Decarboxylative Deuteration of Aromatic Carboxylic Acids http://www.medworm.com/index.php?rid=5482564&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289638 SynthesisDOI: 10.1055/s-0031-1289638AbstractThe practical utility of decarboxylative transformations in organic synthesis is discussed, and the decarboxylative deuteration of (hetero)aromatic carboxylic acids is disclosed as a further example. Various monodeuterated arenes were synthesized under mild conditions, in a single step from easily accessible aromatic carboxylic acids and deuterium oxide. Copper catalysts were found to have the widest scope, but silver catalysts are superior for some ortho-substituted benzoates. A few substrates, e.g. quinoline-2-carboxylic acid, decarboxylate even in the absence of a metal catalyst.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5482564 Mon, 05 Dec 2011 05:00:00 +0100 5482564 (N-tert-Butanesulfinyl)imines in Alkaloid Synthesis: Concise Formal Syntheses of the Dendrobate Alkaloid (+)-241D and Its C-4 Epimer¹ http://www.medworm.com/index.php?rid=5473331&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289634 SynthesisDOI: 10.1055/s-0031-1289634AbstractConcise formal syntheses of the dendrobate alkaloid (+)-241D and its C-4 epimer are described by means of a highly diastereoselective Barbier-type indium-mediated allylation strategy involving an (S)-(N-tert-butanesulfinyl)imine.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5473331 Fri, 02 Dec 2011 05:00:00 +0100 5473331 Lewis Acid Catalyzed Diastereoselective Vinylogous Mannich Reaction Induced by O-Pivaloylated d-Galactosylamine as the Chiral Auxiliary: Stereoselective Synthesis of 6-Arylpiperidin-2-ones http://www.medworm.com/index.php?rid=5473330&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289635 SynthesisDOI: 10.1055/s-0031-1289635AbstractThe diastereospecific formation of β-N-glycosidically linked α,β-unsaturated δ-aminocarbonyl derivatives, in the form of (S)-δ-amino-δ-arylpent-2-enoic ester, has been achieved in high yield via a vinylogous Mannich reaction, utilizing poly-O-pivaloylated d-galacosylamine as the chiral auxiliary. (S)-6-p-Tolylpiperidine-2-one can be stereoselectively synthesized from (S)-δ-amino-δ-arylpent-2-enoic ester by sequential hydrogenation of the double bond, cyclic lactam formation, and removal of the N-glycosidic auxiliary under basic conditions.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5473330 Fri, 02 Dec 2011 05:00:00 +0100 5473330 Selective Protection and Deprotection of ortho-Functionalized Arylphosphonates http://www.medworm.com/index.php?rid=5473329&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289626 SynthesisDOI: 10.1055/s-0031-1289626AbstractFunctionalized aromatic alkylphosphonates, hemi-phosphonates and phosphonic acids are good candidates to elaborate water-soluble building blocks. The key step of the synthesis developed here consisted of the introduction of a phosphoryl group by an ortho-metallation reaction from protected ortho-anisidine. A practical route to phosphonated benzoxazoles was thus discovered. Chemoselective deprotections were investigated and mono-, bis-, and ter-deprotected aromatic derivatives were obtained.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5473329 Fri, 02 Dec 2011 05:00:00 +0100 5473329 Charge-Accelerated Sulfonium [3,3]-Sigmatropic Rearrangements http://www.medworm.com/index.php?rid=5464703&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289632 SynthesisDOI: 10.1055/s-0031-1289632AbstractCharge-accelerated sigmatropic rearrangements are useful reactions for the creation of key C-C bonds in synthesis. In this mini-review, recent developments in sulfonium [3,3]-sigmatropic rearrangements that take place under mild and operationally simple conditions are presented and discussed in a unified manner.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5464703 Thu, 01 Dec 2011 05:00:00 +0100 5464703 Synthesis of a Phenanthridine Analogue of Natural Isocarbostyril Alkaloids http://www.medworm.com/index.php?rid=5464702&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289627 SynthesisDOI: 10.1055/s-0031-1289627AbstractA phenanthridine alkaloid analogue has been synthesized by a short sequence, using a stereoselective hydroxylation process and a Pictet-Spengler reaction. The starting material, 5-(3,4-dimethoxyphenyl)-6-nitrocyclohex-2-enol, is a compound previously reported by us and prepared through a Diels-Alder reaction. The configurational assignment of the starting material, previously done by NMR experiments, was confirmed by X-ray crystallographic analysis.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5464702 Thu, 01 Dec 2011 05:00:00 +0100 5464702 Synthesis of the Indolo[2,3-a]quinolizidine Ring through the Addition of 2-Siloxyfurans to Imines and Intrinsic Reaction Coordinate Calculations http://www.medworm.com/index.php?rid=5464701&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289631 SynthesisDOI: 10.1055/s-0031-1289631AbstractA concise asymmetric diastereoselective strategy for the synthesis of indolo[2,3-a]quinolizidine derivative 1 was developed using diastereoselective addition of 2-siloxyfurans 4 to imine 3 through chiral auxiliary induction. The addition of an ionic liquid as additive in the reaction favored the anti configuration in the major adduct. The stereochemical outcome of the anti/syn (threo/erythro) selectivity was rationalized based on transition state and IRC calculations at DFT (B3LYP) and MP2 theories. MP2 calculations was shown to be the method of choice in these systems, which orbital desymmetrizations were observed in the anti transition state of the addition of 4 to 3 and secondary orbital interactions allowed us to rationalize the production of... Synthesis journals http://www.medworm.com/rss/comments.php?id=5464701 Thu, 01 Dec 2011 05:00:00 +0100 5464701 Enantio- and Diastereoselective Synthesis of β,γ,γ,δ-Tetrasubstituted α-Methylene-δ-lactones http://www.medworm.com/index.php?rid=5464700&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289629 SynthesisDOI: 10.1055/s-0031-1289629AbstractThe synthesis of two α-(diethoxyphosphoryl)-α,β-unsaturated δ-lactones with 98% ee has been developed using (S)-3-aryl-3-hydroxy-2,2-dimethylpropanals, easily accessible via direct, asymmetric organocatalytic aldol reaction, as the starting materials. The lactones were transformed into the corresponding α-methylene-δ-lactones in a two-step process involving Michael addition followed by Horner-Wadsworth-Emmons olefination without loss of enantiomeric purity. Furthermore, it was shown that diastereoselectivity of the Michael addition can be fully controlled by the C6 stereogenic center in the intermediate lactones. A transition-state model rationalizing the stereochemical outcome of the reaction was proposed.[...]© Georg Thieme Verlag Stuttg... Synthesis journals http://www.medworm.com/rss/comments.php?id=5464700 Thu, 01 Dec 2011 05:00:00 +0100 5464700 Synthesis of Sulfonyl Chlorides and Sulfonic Acids in SDS Micelles http://www.medworm.com/index.php?rid=5464704&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289628 SynthesisDOI: 10.1055/s-0031-1289628AbstractH2O2/POCl3 is found to be a reactive reagent system that can be used in sodium dodecyl sulfate (SDS) micellar solution in aqueous media for the direct oxidative chlorination of thiol and di­sulfide derivatives to give the desired sulfonyl chlorides. The oxidation of thiols and disulfides to sulfonic acids with this system is also reported. In most cases, these reactions are highly selective, simple, and clean, affording products in excellent yields and high purity.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5464704 Wed, 30 Nov 2011 05:00:00 +0100 5464704 An Effective Catalytic α-Phosphoryloxylation of Ketones with Iodobenzene http://www.medworm.com/index.php?rid=5464699&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289630 SynthesisDOI: 10.1055/s-0031-1289630AbstractAn effective catalytic method for α-phosphoryloxylation of ketones is reported. When ketones were reacted with phosphates in the presence of iodobenzene as the recyclable catalyst and m-chloroperbenzoic acid as the terminal oxidant in acetonitrile at room temperature, the α-phosphoryloxylation of ketones took place easily and the corresponding keto phosphates were obtained in moderate to good yields.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5464699 Wed, 30 Nov 2011 05:00:00 +0100 5464699 Ecofriendly Oxidative Nuclear Halogenation of Aromatic Compounds Using Potassium and Ammonium Halides http://www.medworm.com/index.php?rid=5447157&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289620 SynthesisDOI: 10.1055/s-0031-1289620AbstractHalogenated aromatic compounds are versatile building blocks in organic synthesis and form an important class of molecules in organic chemistry. A wide variety of methods and reagent systems have been developed to affect their synthesis. This short review presents an overview of methods used for efficient and regio­selective nuclear halogenation of activated aromatic compounds with potassium and ammonium halides.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5447157 Thu, 24 Nov 2011 05:00:00 +0100 5447157 tert-Butoxide-Assisted Amidation of Esters under Green Conditions http://www.medworm.com/index.php?rid=5447156&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289622 SynthesisDOI: 10.1055/s-0031-1289622AbstractEfficient and green amidation reactions are of great importance. In this work, we demonstrate the tert-butoxide-assisted amidation of esters with amines under ambient conditions. Aliphatic and/or aromatic esters were converted into the corresponding amides under mild conditions in good to excellent yields. It is noteworthy that the reaction is highly efficient, rapid, versatile, green and economical, and will find great practical application in organic synthesis, biochemistry, and industrial chemistry.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5447156 Thu, 24 Nov 2011 05:00:00 +0100 5447156 An Environmentally Friendly Synthesis of Michler’s Ketone Analogues in Water http://www.medworm.com/index.php?rid=5447152&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289623 SynthesisDOI: 10.1055/s-0031-1289623AbstractAn environmentally friendly method for the synthesis of a series of novel, unsymmetrical Michler’s ketone analogues, [4-(dialkylamino)phenyl](aryl)methanones, via nucleophilic aromatic substitution of (fluorophenyl)(aryl)methanones with various amines in water­ is described. The reaction products are formed in high yields and additional purification is not required. The aqueous solvent and unreacted amines can be recycled.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5447152 Thu, 24 Nov 2011 05:00:00 +0100 5447152 New Procedure for the Preparation of (1R,2R)-2-[(R)-3-(Benzyloxy)pyr­rolidin-1-yl]cyclohexanol http://www.medworm.com/index.php?rid=5447155&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289619 SynthesisDOI: 10.1055/s-0031-1289619AbstractA novel route to an intermediate of vernakalant, (1R,2R)-2-[(R)-3-(benzyloxy)pyrrolidin-1-yl]cyclohexanol from ethyl (R)-4-chloro-3-hydroxybutanoate is described. It was found that the key intermediate (R)-4-(benzyloxy)-1-[(1R,2R)-2-(tert-butyldimethylsiloxy)cyclohexyl]pyrrolidin-2-one could be isolated with high dia­stereomeric excess (up to 99% de) from its isomer by column chromatography alone, without further chemical resolution.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5447155 Wed, 23 Nov 2011 05:00:00 +0100 5447155 Novel Strategy for the Bis-Butenolide Synthesis via Ring-Closing Metathesis http://www.medworm.com/index.php?rid=5447154&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289621 SynthesisDOI: 10.1055/s-0031-1289621AbstractA new synthesis to bis-butenolide derivatives from inexpensive divinylglycol is described, employing a sequential double acylation followed by a double ring-closing metathesis. The selectivity is affected by the choice of catalyst.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5447154 Wed, 23 Nov 2011 05:00:00 +0100 5447154 5-(p-Tolyl)isoxazol-3-amine-Palladium(II) Complex: Preparation, Structure, and Catalytic Application in the Suzuki-Miyaura Reaction in Water http://www.medworm.com/index.php?rid=5447153&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289618 SynthesisDOI: 10.1055/s-0031-1289618AbstractA air and moisture stable square-planar trans-dichloropalladium(II) complex containing two 5-(p-tolyl)isoxazol-3-amine ligands was synthesized and structurally characterized by single-crystal X-ray diffraction. The isoxazol-3-amine ligand was prepared from 5-(p-tolyl)isoxazole-3-carbaldehyde oxime by successive transformations. The new complex is a high-turnover-number catalyst for the Suzuki-Miyaura reaction with low palladium loading (0.0001-0.1%) in neat water under an air atmosphere.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5447153 Wed, 23 Nov 2011 05:00:00 +0100 5447153 Synthesis of Diamondoid Carboxylic Acids http://www.medworm.com/index.php?rid=5447151&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289617 SynthesisDOI: 10.1055/s-0031-1289617AbstractProcedures for the synthesis of apical mono-, di-, and tricarboxylic acids of triamantane, [121]tetramantane, and [1(2,3)4]pentamantane, apical diacetic acids of diamantane and triamantane, as well as medial propionic acids of diamantane and triamantane were elaborated starting from the corresponding alcohols and bromides. The obtained diamondoid acids were characterized as their methyl ester derivatives.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5447151 Wed, 23 Nov 2011 05:00:00 +0100 5447151 Science of Synthesis, Stereoselective Synthesis 3: Stereoselective Pericyclic Reactions, Cross Coupling, and C-H and C-X Activation http://www.medworm.com/index.php?rid=5436916&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289605 Synthesis 2011; 2011: 3927-3927DOI: 10.1055/s-0031-1289605© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.Article in Thieme eJournals:Table of contents (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5436916 Tue, 22 Nov 2011 05:00:00 +0100 5436916 Synform issue 2011/12 http://www.medworm.com/index.php?rid=5436915&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289431 Synthesis 2011; 2011: A109-A118DOI: 10.1055/s-0031-1289431© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.Article in Thieme eJournals:Table of contents (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5436915 Tue, 22 Nov 2011 05:00:00 +0100 5436915 Organozirconium Chemistry on Cyclosporin: A Novel Process for the Highly Stereoselective Synthesis of (E)-ISA247 (Voclosporin) and Close Analogues http://www.medworm.com/index.php?rid=5436914&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289616 SynthesisDOI: 10.1055/s-0031-1289616AbstractApplication of organozirconium chemistry to cyclosporin has led to the development of a novel process for the highly stereoselective synthesis of the E-isomer of ISA247 (voclosporin), which is a potent immunosuppressive agent currently in late stage human clinical trials for treatment of psoriasis, prevention of kidney transplant rejection, and ophthalmic indications. Synthesis of deuterated analogues of ISA247 and a cyclosporin triene analogue using the same methodology is also described.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5436914 Tue, 22 Nov 2011 05:00:00 +0100 5436914 Regioselective Syntheses of Substituted Pyridines and 2,2′-Bipyridines by Cobalt-Catalyzed [2+2+2] Cycloaddition of α,ω-Diynes with Nitriles http://www.medworm.com/index.php?rid=5436913&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289596 Synthesis 2011; 2011: 3928-3928DOI: 10.1055/s-0031-1289596© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  FREE Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5436913 Tue, 22 Nov 2011 05:00:00 +0100 5436913 Science of Synthesis, Stereoselective Synthesis 2: Stereoselective Reactions of Carbonyl and Imino Groups http://www.medworm.com/index.php?rid=5436912&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289604 Synthesis 2011; 2011: 3926-3926DOI: 10.1055/s-0031-1289604© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.Article in Thieme eJournals:Table of contents (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5436912 Tue, 22 Nov 2011 05:00:00 +0100 5436912 Science of Synthesis, Stereoselective Synthesis 1: Stereoselective Reactions of Carbon-Carbon Double Bonds http://www.medworm.com/index.php?rid=5436911&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289603 Synthesis 2011; 2011: 3925-3925DOI: 10.1055/s-0031-1289603© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.Article in Thieme eJournals:Table of contents (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5436911 Tue, 22 Nov 2011 05:00:00 +0100 5436911 Unusual Regioselective Reactions of 2,4-Bis(methylsulfanyl)pyrimidine under Modified Suzuki and Stille Cross-Coupling Conditions http://www.medworm.com/index.php?rid=5436910&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289615 SynthesisDOI: 10.1055/s-0031-1289615Abstract2,4-Bis(methylsulfanyl)pyrimidine undergoes unusual regioselective cross-coupling reactions with aryl boronic acids and organostannanes in the presence of copper(I) 3-methylsalicylate or copper(I) thiophene-2-carboxylate as a cofactor to give 2-aryl-4-(methylsulfanyl)pyrimidines as the major products. The structures of the products of the coupling reaction were established by X-ray crystallography.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5436910 Tue, 22 Nov 2011 05:00:00 +0100 5436910 Electroreduction of Triphenylphosphine Oxide to Triphenylphosphine in the Presence of Chlorotrimethylsilane http://www.medworm.com/index.php?rid=5427734&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289612 SynthesisDOI: 10.1055/s-0031-1289612AbstractElectroreduction of triphenylphosphine oxide to triphenylphosphine in an acetonitrile solution of tetrabutylammonium bromide in the presence of chlorotrimethylsilane was performed successfully in an undivided cell fitted with a zinc anode and a platinum cathode under constant current. A plausible mechanism involving, (1) one-electron reduction of triphenylphosphine oxide generating the corresponding anion radical [Ph3PË™-O-], (2) subsequent reaction with chlorotrimethylsilane affording the (trimethylsiloxy)triphenylphosphorus radical [Ph3PË™-OSiMe3], and (3) further one-electron reduction followed by P-O bond fission leading to triphenylphosphine is proposed. In a similar manner, electroreduction of some triarylphosphine oxides and alkyldiarylpho... Synthesis journals http://www.medworm.com/rss/comments.php?id=5427734 Fri, 18 Nov 2011 05:00:00 +0100 5427734 Non-Cyclizing Direct Transformation of Arene Carbon-Hydrogen Bonds into Carbon-Nitrogen Bonds http://www.medworm.com/index.php?rid=5427733&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289614 SynthesisDOI: 10.1055/s-0031-1289614AbstractThis review covers advances in the non-cyclizing direct transformations of arene carbon-hydrogen bonds into carbon-nitrogen bonds, including carbon-nitrogen bond formations for arenes bearing directing groups, for polyfluoroarenes, and for alkyl-substituted arenes. Copper catalysis, palladium catalysis and metal-free strategies for carbon-nitrogen bond formation are discussed.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5427733 Fri, 18 Nov 2011 05:00:00 +0100 5427733 Microwave-Assisted Solvent-Free Diels-Alder Reaction - A Fast and Simple Route to Various 5,6-Substituted Norbornenes and Polychlorinated Norbornenes http://www.medworm.com/index.php?rid=5427732&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289610 SynthesisDOI: 10.1055/s-0031-1289610AbstractA series of 5,6-substituted norbornenes and 5,6-substituted polychlorinated norbornenes was prepared by using a microwave-assisted Diels-Alder reaction. This procedure proved very versatile, fast, and with an easy workup step, and therefore suitable even for large-scale synthesis.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5427732 Fri, 18 Nov 2011 05:00:00 +0100 5427732 A Convenient Synthesis of Novel 2,8-Disubstituted Pyrido[3,4-b]pyrazines Possessing Biological Activity http://www.medworm.com/index.php?rid=5427731&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289613 SynthesisDOI: 10.1055/s-0031-1289613AbstractA regioselective synthetic route to 2,8-disubstituted pyrido[3,4-b]pyrazines, by initial condensation reaction between suitable diaminopyridines and α-keto aldehydes equivalents, has been developed. Focusing on the functionalization on C-8, 2-aryl-8-bromo- and 8-amino-2-arylpyrido[3,4-b]pyrazines have been synthesized. Anilines, amides, and ureas have been introduced at the 8-position from key intermediates. 2,8-Disubstituted pyrido[3,4-b]pyrazines thus prepared were found to be of biological interest.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5427731 Fri, 18 Nov 2011 05:00:00 +0100 5427731 Cationic Late-Transition-Metal Complexes Catalyze the Ring Opening of Aziridines with Amines http://www.medworm.com/index.php?rid=5427730&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289611 SynthesisDOI: 10.1055/s-0031-1289611AbstractCationic palladium and nickel complexes have been found to catalyze the ring-opening of meso-N-aryl aziridines with anilines very efficiently and furnish valuable 1,2-diamines in typically excellent yields. The active catalysts were generated in situ from the corresponding metal dichloride bis(triphenylphosphine) complexes through chloride abstraction with a silver salt. This new protocol is applicable across a broad substrate range with both cyclic as well as acyclic aziridines. In addition, cationic gold-phosphine complexes proved to be highly reactive as well as delivering products in comparable rates and yields.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (So... Synthesis journals http://www.medworm.com/rss/comments.php?id=5427730 Fri, 18 Nov 2011 05:00:00 +0100 5427730 Synthesis of α-Trifluoromethyl-α-hydroxy Acid-Peptide Conjugates via Click Chemistry http://www.medworm.com/index.php?rid=5427735&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289609 SynthesisDOI: 10.1055/s-0031-1289609AbstractA simple and convenient method for the incorporation of fluorinated α-hydroxy acids into peptides is described. The target conjugates were obtained from α-alkynyl-α-trifluoromethyl-α-hydroxy acids and azido peptides via the copper(I)-catalyzed Huisgen cycloaddition reaction (click chemistry). After straightforward deprotection, the α-trifluoromethyl-α-hydroxy acid containing peptides may find important applications in biochemistry and medicinal chemistry.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5427735 Thu, 17 Nov 2011 05:00:00 +0100 5427735 Click Chemistry: An Efficient Synthesis of Heterocycles Substituted with Steroids, Saponins, and Digitalis Analogues http://www.medworm.com/index.php?rid=5416894&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289606 SynthesisDOI: 10.1055/s-0031-1289606AbstractThe copper-catalyzed azide-alkyne cycloaddition (CuAAC) has been used for the construction of 1,2,3-triazole containing steroids in good to excellent yields. Combination of propargylic glycosides and steroidal azides as reaction partner allowed the synthesis of a privileged class of natural product analogues. The versatility of this protocol makes this chemistry a useful attractive approach for the synthesis of target molecules.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5416894 Wed, 16 Nov 2011 05:00:00 +0100 5416894 Copper(II) Triflate Promoted One-Pot Synthesis of Coumarin-, Quinolone-, and Naphthalene-Annulated 2-Aminothiazoles under Ligand-Free Conditions http://www.medworm.com/index.php?rid=5416895&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289608 SynthesisDOI: 10.1055/s-0031-1289608AbstractAn efficient synthesis of new 2-aminothiazole-annulated compounds is described via copper(II) triflate promoted sequential condensation, arylation, and heterocyclization reactions in one step. The reaction is compatible with a variety of substrates providing efficient access to many biologically important skeletons in good yields.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5416895 Tue, 15 Nov 2011 05:00:00 +0100 5416895 Novel σ1 Receptor Ligands by Oxa-Pictet-Spengler Reaction of Pyrazolylethanol http://www.medworm.com/index.php?rid=5416893&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289607 SynthesisDOI: 10.1055/s-0031-1289607AbstractThe oxa-Pictet-Spengler reaction of 2-(1-phenylpyrazol-5-yl)ethanol required the weak acid pyridinium p-toluenesulfonate to provide pyrano[4,3-c]pyrazoles with additional functional groups in the side chain. These functional groups allow the introduction of various amino substituents into the side chain in position 4. In receptor binding studies the aminoethyl-substituted pyranopyrazoles revealed higher σ1 receptor affinities and σ1/σ2 selectivities than the shorter aminomethyl homologues. The pyranopyrazole bearing the phenylpiperidine substituent (Ki = 0.99 nM) represents the most potent and that bearing the piperidine substituent the most selective (σ1/σ2 = 180) σ1 ligands of this series of compounds.[...]© Georg Thieme Verlag S... Synthesis journals http://www.medworm.com/rss/comments.php?id=5416893 Tue, 15 Nov 2011 05:00:00 +0100 5416893 A Novel Method for the Synthesis of (1,8-Dioxo-2,3,4,5,6,7,8,9-octahydro-1H-xanthen-9-yl)acetic Acids on Solid Phase http://www.medworm.com/index.php?rid=5416896&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289602 We report the first solid-phase synthesis of (1,8- dioxo-2,3,4,5,6,7,8,9-octahydro-1H-xanthen-9-yl)acetic acids via a tandem Michael-Michael cyclization with resin-bound propiolic acid as Michael acceptor and cyclohexanediones.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5416896 Fri, 11 Nov 2011 05:00:00 +0100 5416896 New Method for the Synthesis of Sulforaphane and Related Isothiocyanates http://www.medworm.com/index.php?rid=5416892&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289601 SynthesisDOI: 10.1055/s-0031-1289601AbstractThe biologically important isothiocyanate sulforaphane (4-isothiocyanatobutyl methyl sulfoxide) was synthesized in six simple steps from commercially available 4-aminobutan-1-ol with an overall yield of 64%. The new synthetic method is suitable for multigram-scale preparation of sulforaphane and does not require expensive or toxic reagents. A novel one-pot procedure was also developed for preparing isothiocyanates through reaction of amines with O-phenyl chlorothioformate under mild conditions. Additionally, methyl pyrrolidine-1-carbodithioate was obtained as an unexpected byproduct, and this protocol was shown to be useful for the synthesis of S-aryl or S-heterocyclic thiocarbamates with cyclic side chains.[...]© Georg Thieme Verlag Stuttgart Ë... Synthesis journals http://www.medworm.com/rss/comments.php?id=5416892 Fri, 11 Nov 2011 05:00:00 +0100 5416892 Convenient Synthesis of Ethenylcyclopropane and Some 2-Cyclopropylcyclopropane Derivatives¹ http://www.medworm.com/index.php?rid=5416891&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289600 SynthesisDOI: 10.1055/s-0031-1289600AbstractEthenylcyclopropane (5) was prepared from cyclopropyl methyl ketone (1) in four simple, easily scalable steps (bromination, reduction to the bromohydrin, acetylation of the latter, and reductive elimination with Zn/Cu) in an overall yield of 56%. 1-Bromo-2-cyclopropylcyclopropane (7) (approximately 1:1 mixture of cis- and trans-7) was prepared from 5 via the dibromide 6, and from 7 the boronate cis/trans-8 (ratio 1:1) was obtained in 96% yield. Rhodium(II)-catalyzed cyclopropanation of 5 with ethyl diazoacetate gave ethyl 2-cyclopropylcyclopropanecarboxylate (cis/trans-9, ratio 1:1.4) in 80% yield. The latter was also prepared in 79% overall yield by sequential cyclopropanation of buta-1,3-diene with ethyl diazoacetate [under Rh2(OAc)4 catalysis]... Synthesis journals http://www.medworm.com/rss/comments.php?id=5416891 Fri, 11 Nov 2011 05:00:00 +0100 5416891 d-Gluco-hept-2-ulose and Novel Deoxyfluoro Derivatives as Seven-Carbon Analogues of F-Deoxy-d-glucose (FDG) http://www.medworm.com/index.php?rid=5396007&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289598 SynthesisDOI: 10.1055/s-0031-1289598AbstractKetoheptoses, seven-carbon sugars, were recognized to display pharmacological properties that are potentially suitable for in vivo diagnostic of diabetes and cancers using ¹9F-MRI. The present paper describes efficient syntheses towards ketoheptoses and exemplary a series of regioisomeric fluoro derivatives of d-gluco-hept-2-ulose.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5396007 Wed, 09 Nov 2011 05:00:00 +0100 5396007 Three-Component Synthesis of Some Novel N-Heterocycle Methyl-O-oxime Ethers http://www.medworm.com/index.php?rid=5396006&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289599 SynthesisDOI: 10.1055/s-0031-1289599AbstractA convenient and highly efficient protocol for one-pot synthesis of some novel N-heterocycle methyl-O-oxime ethers is described. In this method, three-component coupling of different types of ketoximes, with methylene iodide and nitrogen heterocycles, including imidazoles, benzimidazole, benzotriazole, and theophylline in the presence of an equimolar mixture of K2CO3/Et3N in refluxing MeCN furnished the corresponding N-heterocycle methyl-O-oxime ethers in good yields. This methodology is highly efficient for the synthesis of various structurally diverse N-heterocycle methyl-O-oxime ethers. The results of quantum mechanical studies on reaction intermediates are discussed.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:... Synthesis journals http://www.medworm.com/rss/comments.php?id=5396006 Wed, 09 Nov 2011 05:00:00 +0100 5396006 Convenient and Practical Synthesis of α-Amido Stannanes http://www.medworm.com/index.php?rid=5396004&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289597 SynthesisDOI: 10.1055/s-0031-1289597AbstractConvenient and practical synthesis of N-Boc- and N-Cbz-α-amino stannanes from the corresponding α-amido sulfones was achieved. Yields of products are generally good to high because of the consequence of avoiding the isolation of unstable imine intermediates. The procedure is so simple that large-scale stannylation is possible without any difficulty.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5396004 Wed, 09 Nov 2011 05:00:00 +0100 5396004 Inexpensive Phthalic Acid Promoted Domino Povarov Reaction between Anilines and N-Vinylamides: An Efficient Preparation of Privileged 4-Substituted 2-Methyl-1,2,3,4-tetrahydroquinoline Scaffolds http://www.medworm.com/index.php?rid=5396005&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289591 SynthesisDOI: 10.1055/s-0031-1289591AbstractAn efficient and simple synthesis of new 2-methyl-1,2,3,4-tetrahydroquinolines with C4 amide fragments based on the phthalic acid promoted domino Povarov reaction between anilines and N-vinylamides has been developed.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5396005 Tue, 08 Nov 2011 05:00:00 +0100 5396005 Supported Synthesis of Halogenated Organic Compounds http://www.medworm.com/index.php?rid=5395999&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289590 SynthesisDOI: 10.1055/s-0031-1289590AbstractHalogenated organic compounds are highly sought after in a wide variety of fields, for example synthetic and medicinal chemistry as well as materials science. The supported synthesis of organohalogens has been extensively developed in the field of imaging where rapid purification of radiotracers containing isotopes with short half-lives is of great importance. Electrophilic and nucleophilic halogenation occurs upon cleavage from the support and the desired labeled product is readily separated from contaminants. This review provides a discussion as to how supported synthetic routes have facilitated the preparation of halogenated compounds.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstrac... Synthesis journals http://www.medworm.com/rss/comments.php?id=5395999 Tue, 08 Nov 2011 05:00:00 +0100 5395999 (R)-[(2-Oxo-4-thiazolidinyl)methyl]triphenylphosphonium Iodide: A Wittig Reagent for the Synthesis of Cysteine-Derived Alkenes http://www.medworm.com/index.php?rid=5396000&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289583 SynthesisDOI: 10.1055/s-0031-1289583Abstract(R)-[(2-Oxo-4-thiazolidinyl)methyl]triphenylphosphonium iodide (1), readily prepared in five steps from l-cysteine ethyl ester (39% overall on a 500 g scale), is a useful Wittig reagent for the synthesis of cysteine-derived alkenes such as those found in dipeptide isosteres and peptidomimetics. Preparation of 1 and its use in Wittig olefination reactions with aldehydes is described. The resulting thiazolidinone compounds are readily unmasked to provide the corresponding thiol, symmetrical disulfide, or S-trityl derivatives.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5396000 Mon, 07 Nov 2011 05:00:00 +0100 5396000 A Straightforward Approach to Protected (S)-Dolaphenine (Doe), the Unusual Amino Acid Component of Dolastatin 10 http://www.medworm.com/index.php?rid=5395998&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289594 SynthesisDOI: 10.1055/s-0031-1289594AbstractA short, four-step synthesis of Boc-protected (S)-dolaphenine is described, starting from protected phenylalanyl glycine. The key step is the cyclization of an endothiodipeptide to give a thiazolyl­ triflate, which can be subjected to a palladium-catalyzed reduction with formic acid.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5395998 Mon, 07 Nov 2011 05:00:00 +0100 5395998 Mechanistic Studies on a New Catalyst System (CuI-NaHSO4×SiO2) Leading to the One-Pot Synthesis of Imidazo[1,2-a]pyridines from Reactions of 2-Aminopyridines, Aldehydes, and Terminal Alkynes http://www.medworm.com/index.php?rid=5395997&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289297 Synthesis 2011; 2011: e3-e3DOI: 10.1055/s-0031-1289297© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  FREE Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5395997 Mon, 07 Nov 2011 05:00:00 +0100 5395997 On the Dual Role of N-Heterocyclic Carbenes as Bases and Nucleophiles in Reactions with Organic Halides http://www.medworm.com/index.php?rid=5395996&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289593 SynthesisDOI: 10.1055/s-0031-1289593AbstractThe synthetic consequences of different basicities, nucleophilicities, and sterics of N-heterocyclic carbenes have been studied in reactions of imidazolin-2-ylidenes with organic halides. Highly nucleophilic and less basic carbenes cleanly gave alkyli­deneimidazolines, the deoxy analogues of Breslow-type intermediates. More basic NHCs engaged in unwanted deprotonation or dehydrohalogenation reactions.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5395996 Mon, 07 Nov 2011 05:00:00 +0100 5395996 One-Pot Synthesis of Isocyanides from Alcohols http://www.medworm.com/index.php?rid=5396003&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289592 SynthesisDOI: 10.1055/s-0031-1289592AbstractA one-pot reaction of alcohols with trimethylsilyl cyanide and methanesulfonic acid with subsequent neutralization by triethylamine and dehydration by tosyl chloride and pyridine gave the corresponding isocyanides in moderate-to-high yields. This method was used to synthesize tertiary and benzylic isocyanides from the corresponding alcohols.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5396003 Fri, 04 Nov 2011 04:00:00 +0100 5396003 A Practical, Laboratory-Scale Synthesis of Perampanel http://www.medworm.com/index.php?rid=5396002&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289587 SynthesisDOI: 10.1055/s-0031-1289587AbstractThe orally active, noncompetitive, selective AMPA receptor antagonist Perampanel, 2-[1′,6′-dihydro-6′-oxo-1-phenyl-(2′,3′-bipyridin)-5′-yl]benzonitrile, has been prepared from readily available, relatively inexpensive starting materials. The synthesis was carried out on a laboratory scale with no specialized equipment, and involved only two chromatographic purifications.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5396002 Fri, 04 Nov 2011 04:00:00 +0100 5396002 Desymmetrization of Hepta-1,6-dien-4-ol by Prins Reaction and Subsequent Cross-Metathesis: Access to Diospongine A Homologues http://www.medworm.com/index.php?rid=5396001&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289588 SynthesisDOI: 10.1055/s-0031-1289588AbstractA new tetrahydropyran scaffold has been efficiently prepared by Prins reaction between hepta-1,6-dien-4-ol and benzaldehyde. Subsequent functionalizations were further achieved by Mitsunobu reaction and/or by the way of cross-metathesis/Wacker oxidation sequence to deliver diospongin A analogues.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5396001 Fri, 04 Nov 2011 04:00:00 +0100 5396001 A Sustainable Procedure Combining the Advantages of Both Homogeneous and Heterogeneous Catalysis for the Heck-Matsuda Reaction http://www.medworm.com/index.php?rid=5374310&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289585 SynthesisDOI: 10.1055/s-0031-1289585AbstractA sustainable procedure has been introduced for the Heck-Matsuda reaction between arenediazonium salts and olefins. Our approach advantageously combines the high reactivity attained in homogeneous catalysis with the recovery of palladium metal by simple filtration usually encountered in heterogeneous catalysis. To reach such a useful catalytic system, a homogeneous source of palladium, Pd(OAc)2, reduced into a catalytically active soluble palladium species, was used in the presence of charcoal and deposited progressively onto the support when it became inactive. Measurement of palladium content shows only a low contamination of the solvent and the product after simple filtration.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme e... Synthesis journals http://www.medworm.com/rss/comments.php?id=5374310 Thu, 03 Nov 2011 04:00:00 +0100 5374310 Preparation of α-Hydroxy-β-Fmoc Amino Acids from N-Boc Amino Acids http://www.medworm.com/index.php?rid=5374308&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289586 SynthesisDOI: 10.1055/s-0031-1289586AbstractA general method for the conversion of N-Boc amino acids­ into their homologated α-hydroxy-β-Fmoc amino acids is described. The protocol involved preparation of the amino aldehyde by reduction of the corresponding Weinreb amides, hydrocyanation, and hydrolysis of the nitrile group, followed by reprotection of the amino acid as the Fmoc derivative.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5374308 Thu, 03 Nov 2011 04:00:00 +0100 5374308 A Combinatorial Approach towards a Library of Chiral γ-Lactams and 2,3-Disubstituted Pyrroles http://www.medworm.com/index.php?rid=5374307&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289584 SynthesisDOI: 10.1055/s-0031-1289584AbstractA library of heterocyclic products with a wide variety of organic residues is produced via a four-component reaction of α,β-unsaturated aldehydes, primary amines, carbon monoxide, and ethylene using a multi-reactor station with an array of 96 autoclaves employing the same high-pressure reaction conditions for all catalytic reactions. In the presence of Ru3(CO)12 as a precatalyst, mixtures of chiral γ-lactams and 2,3-disubstituted pyrroles are obtained. This combinatorial approach also enables us for the first time to set up rules relating to the effects of specific substituents in the substrates on the outcome of the respective catalytic reaction.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  ... Synthesis journals http://www.medworm.com/rss/comments.php?id=5374307 Thu, 03 Nov 2011 04:00:00 +0100 5374307 A Concise One-Pot Approach to the Synthesis of 4-(1H-Indol-3-yl)quinolines http://www.medworm.com/index.php?rid=5374305&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289589 SynthesisDOI: 10.1055/s-0031-1289589AbstractAn operationally simple procedure, involving conjugate addition of NaI to β-(2-aminophenyl)-α,β-ynones/cyclization/Pd-catalyzed reaction with 2-alkynyl-trifluoroacetanilides, afforded 4-(1H-indol-3-yl)quinolines. The whole process was carried out in the same flask, without any intermediate work-up and using ethanol as solvent.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5374305 Thu, 03 Nov 2011 04:00:00 +0100 5374305 Synthesis of Coumarins and Neoflavones through Zinc Chloride Catalyzed Hydroarylation of Acetylenic Esters with Phenols http://www.medworm.com/index.php?rid=5374314&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289576 SynthesisDOI: 10.1055/s-0031-1289576AbstractAcetylenic esters react with oxygenated phenols under solvent-free conditions in the presence of only 5 mol% of zinc chloride as a catalyst to give coumarins and neoflavones in reasonable-to-good yields.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5374314 Thu, 27 Oct 2011 04:00:00 +0100 5374314 Synthesis of Functionalized Benzoboroxoles for the Construction of Boronolectins http://www.medworm.com/index.php?rid=5374313&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289577 In conclusion, versatile functionalized benzoboroxoles are reported that can be used for the construction of larger conjugates by peptide coupling or copper-mediated cycloadditions (click reactions) with azides.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5374313 Thu, 27 Oct 2011 04:00:00 +0100 5374313 Multicomponent Synthesis of New Primaquine Thiazolidinone Derivatives http://www.medworm.com/index.php?rid=5374312&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289580 SynthesisDOI: 10.1055/s-0031-1289580AbstractPrimaquine thiazolidinone derivatives, potentially useful as antimalarial agents, were synthesized in good yields by multicomponent reactions of primaquine diphosphate, mercaptoacetic acid, and an optionally substituted benzaldehyde or cyclohexanone for two to four hours. All the products were characterized by ¹H and ¹³C NMR spectroscopy and by LC-MS.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5374312 Thu, 27 Oct 2011 04:00:00 +0100 5374312 Synthesis of Unsymmetrical Polysubstituted Pyridines from β-Sulfonylvinylamines via 1-Aza-Allyl Anion Intermediates http://www.medworm.com/index.php?rid=5374311&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289578 SynthesisDOI: 10.1055/s-0031-1289578AbstractA modular synthesis of highly functionalized unsymmetrical pyridines has been developed from reacting β-sulfonylvinylamines with α,β-unsaturated systems in the presence of base via the formation of 1-aza-allyl anion intermediates.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5374311 Thu, 27 Oct 2011 04:00:00 +0100 5374311 Developments in Transition-Metal-Catalyzed Reactions Using Electrophilic Nitrogen Sources http://www.medworm.com/index.php?rid=5374309&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289581 SynthesisDOI: 10.1055/s-0031-1289581AbstractThe importance of forming C-N bonds has spurred the development of reactions using electrophilic nitrogen reagents. Recently transition-metal catalysts have been developed for use with electrophilic nitrogen sources, resulting in a number of useful C-N bond-forming reactions. This review article summarizes recent progress in this field.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5374309 Thu, 27 Oct 2011 04:00:00 +0100 5374309 A New and Convenient Method for the Preparation of Functionalized Phosphorothioates http://www.medworm.com/index.php?rid=5374306&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289582 SynthesisDOI: 10.1055/s-0031-1289582AbstractA new and efficient method for the synthesis of alkyl and aryl phosphorothioates in high yields via the reaction of (5,5-dimethyl-2-thioxo-1,3,2-dioxaphosphorin-2-yl)disulfanyl derivatives with trimethyl phosphite is described.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5374306 Thu, 27 Oct 2011 04:00:00 +0100 5374306 Syntheses of Aggregation Pheromones of the Palm Weevils Rhyncophorus vulneratus and R. phoenicis and of (+)-trans-Whiskey Lactone http://www.medworm.com/index.php?rid=5374304&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289579 SynthesisDOI: 10.1055/s-0031-1289579Abstract(3S,4S)-3-Methyloctan-4-ol, (4S,5S)-4-methylnonan-5-ol, and (+)-trans-whiskey lactone [(4S,5R)-5-butyl-4-methyldihydrofuran-2(3H)-one] were synthesized stereoselectively by using a radical cyclization reaction as a key step. All three molecules were synthesized from a common cyclic acetal intermediate.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5374304 Thu, 27 Oct 2011 04:00:00 +0100 5374304 A Novel and Enantioselective Total Synthesis of (20S)-Camptothecin via a Sharpless Asymmetric Dihydroxylation Strategy http://www.medworm.com/index.php?rid=5354749&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289575 SynthesisDOI: 10.1055/s-0031-1289575AbstractA novel and efficient asymmetric total synthesis of (20S)-camptothecin has been accomplished in an overall yield of 12% starting from the commercially available 2-methoxynicotinic acid. The key step in the sequence is the Sharpless asymmetric dihydroxylation of a 4-(but-1-en-2-yl)pyridine derivative to establish the stereocenter of (20S)-camptothecin.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5354749 Tue, 25 Oct 2011 04:00:00 +0100 5354749 The Use of COP-OAc in the Catalyst-Controlled Syntheses of 1,3-Polyols http://www.medworm.com/index.php?rid=5354748&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289574 SynthesisDOI: 10.1055/s-0031-1289574AbstractAn iterative strategy to the 1,3-polyol motif is described. The use of the catalytic asymmetric Overman esterification for the construction of all stereogenic centers is broadly examined as are the sequences to extend the developing polyol chain. The iterative strategies are applied to the total syntheses of rugulactone and polyrhacitides A and B.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5354748 Tue, 25 Oct 2011 04:00:00 +0100 5354748 Synform issue 2011/11 http://www.medworm.com/index.php?rid=5343147&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289251 Synthesis 2011; 2011: A100-A108DOI: 10.1055/s-0031-1289251© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.Article in Thieme eJournals:Table of contents (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5343147 Fri, 21 Oct 2011 04:00:00 +0100 5343147 Click Chemistry Applied in the Synthesis of Symmetrical Triphenylene-Based Discotic Liquid-Crystalline Dimers http://www.medworm.com/index.php?rid=5343146&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289573 SynthesisDOI: 10.1055/s-0031-1289573AbstractSymmetrical triphenylene dimers connected by a bis-triazole moiety have been synthesized and characterized. The bis-triazole part is formed as final step utilizing a straightforward double click reaction (CuAAC) allowing further structural variations of the linker. The 1,3-bis(triazol-1-yl)propyltriphenylene-based dimer display columnar mesophase over a wide range of temperatures starting at ambient temperature.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5343146 Fri, 21 Oct 2011 04:00:00 +0100 5343146 Microwave-Assisted One-Pot Synthesis of Pyrazolo[3,4-b]indoles and New Isoxazolo[5,4-b]indoles via Copper-Catalyzed Intramolecular C-N/C-O Bond Formation http://www.medworm.com/index.php?rid=5343141&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289572 SynthesisDOI: 10.1055/s-0031-1289572AbstractA facile one-pot, two-step synthesis of highly substituted pyrazolo[3,4-b]indoles and isoxazolo[5,4-b]indoles was developed via microwave-assisted, copper-catalyzed intramolecular heterocyclization (involving C-N/C-O bond formation) from 3-acetyl-2-chloroindoles in good to excellent yields.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5343141 Fri, 21 Oct 2011 04:00:00 +0100 5343141 Boron Trihalide Mediated Haloallylation of Aryl Aldehydes and Its Application to the Preparation of (E)-1,3-Dienes http://www.medworm.com/index.php?rid=5343150&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289304 SynthesisDOI: 10.1055/s-0031-1289304AbstractIn the presence of boron trihalides, aryl aldehydes couple readily with allylmetals to afford haloallylated products. The reactions tolerate a variety of functional groups. Simple aqueous workup of haloallylation reactions, followed by treatment with 1,8-diazabicyclo[5.4.0]undec-7-ene, provides a straightforward route to synthetically useful (E)-1,3-dienes. The mild reaction conditions, readily available starting materials, and high stereoselectivity make this two-step (E)-1,3-diene synthesis quite attractive.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5343150 Thu, 20 Oct 2011 04:00:00 +0100 5343150 An Efficient Procedure for the Synthesis of α,β-Unsaturated Ketones and Its Application to Heterocyclic Systems http://www.medworm.com/index.php?rid=5343149&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289571 SynthesisDOI: 10.1055/s-0031-1289571AbstractAn efficient and room-temperature procedure is developed for high yield synthesis of novel α,β-unsaturated derivatives of thiopyran 3 directly from ketone 1 and various aldehydes in the presence of catalytic quantities of TMSNMe2 and MgBr2Ë™OEt2 under solvent-free conditions. The main advantage of the procedure is that the formation of the undesired bis by-products is minimized. In addition, the procedure is applicable to other enolizable carbocyclic and acyclic ketones.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5343149 Thu, 20 Oct 2011 04:00:00 +0100 5343149 Birch Reaction Followed by Asymmetric Iridium-Catalysed Hydrogenation http://www.medworm.com/index.php?rid=5343148&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289569 SynthesisDOI: 10.1055/s-0031-1289569AbstractBirch reaction products are asymmetrically hydrogenated with high enantio- and diastereoselectivity via iridium catalysts. This new method of producing chiral compounds was explored for a variety of 1,3-di- and 1,2,4-tri-substituted cyclohexadienes.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5343148 Thu, 20 Oct 2011 04:00:00 +0100 5343148 Efficient Synthesis of Novel Jolkinolides and Related Derivatives Starting from Stevioside http://www.medworm.com/index.php?rid=5343145&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289293 SynthesisDOI: 10.1055/s-0031-1289293AbstractJolkinolides are naturally occurring tetracyclic diterpene from Euphorbia genus, which exhibit promising antitumor and other biological activity. Efficient syntheses of the 19-carboxy derivative of jolkinolide A and 19-hydroxyjolkinolide E have been accomplished in 13 steps with a total yield of 7.8% starting from the easily available and low-cost sweetener stevioside, and some related derivatives have also been synthesized.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5343145 Thu, 20 Oct 2011 04:00:00 +0100 5343145 A Modified and Highly Useful Protocol for the Brønsted Acid Catalyzed, Enantioselective, Vinylogous Mannich Reaction with Aliphatic Aldimines http://www.medworm.com/index.php?rid=5343144&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289303 SynthesisDOI: 10.1055/s-0031-1289303AbstractHighly enantioselective as well as diastereoselective catalytic vinylogous Mannich reactions have been accomplished for the first time with aliphatic straight-chain aldimines and O,O-silylketene acetals and furnish valuable synthetic building blocks in high enantiomeric purity.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5343144 Thu, 20 Oct 2011 04:00:00 +0100 5343144 A Practical Synthesis of (-)-Kainic Acid http://www.medworm.com/index.php?rid=5343142&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289570 SynthesisDOI: 10.1055/s-0031-1289570AbstractA highly practical total synthesis of (-)-kainic acid has been accomplished. The synthesis features the stereoselective alkylation of an iodolactone intermediate efficiently prepared from (+)-carvone and introduction of carboxylic acid by hydrolysis of a nitrile accompanied by epimerization.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5343142 Thu, 20 Oct 2011 04:00:00 +0100 5343142 [2.2]Paracyclophane Derivatives: Synthesis and Application in Catalysis http://www.medworm.com/index.php?rid=5343151&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289296 SynthesisDOI: 10.1055/s-0031-1289296AbstractAdvances in the field of [2.2]paracyclophane chemistry are reviewed including syntheses, resolution of enantiomers and application in organic synthesis. Transition-metal catalyzed as well as organocatalytic transformations are presented focusing on the development of [2.2]paracyclophane derived ligands and catalysts.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5343151 Wed, 19 Oct 2011 04:00:00 +0100 5343151 Synthesis of 1,2,3-Triazole-Fused Heterocycles via Intramolecular Azide-Alkyne Cycloaddition Reactions http://www.medworm.com/index.php?rid=5343143&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289295 SynthesisDOI: 10.1055/s-0031-1289295AbstractThis brief review article describes the progress made in the synthesis of 1,2,3-triazole-fused heterocycles, over the last ten years, mainly by azide-alkyne cycloaddition reactions. In this article, the emphasis is on the various aspects of 1,3-dipolar cycloaddition reactions, especially intramolecular azide-alkyne dipolar cycloaddition reactions.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5343143 Wed, 19 Oct 2011 04:00:00 +0100 5343143 Palladium-Catalyzed Intramolecular Decarboxylative Allylation of (2-Trimethylstannyl)allyl β-Oxocarboxylates http://www.medworm.com/index.php?rid=5330071&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289302 SynthesisDOI: 10.1055/s-0031-1289302AbstractThe present work describes the synthesis of α-(2-tri­methylstannyl)allyl ketones via the palladium-catalyzed decarboxylative allylation of cyclic (2-trimethylstannyl)allyl carboxylates. An example of the synthetic potential for forming polycyclic systems using this methodology is discussed.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5330071 Mon, 17 Oct 2011 04:00:00 +0100 5330071 Asymmetric Syntheses of S,S-Dialkyl-Substituted Sulfoximines and Related Heterocycles http://www.medworm.com/index.php?rid=5330070&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0030-1260260 SynthesisDOI: 10.1055/s-0030-1260260AbstractEnantiomerically enriched forms of a sulfoximine-based myristic acid analogue are prepared using either an asymmetric desymmetrization with a chiral base, or an enantioselective oxidation procedure as key steps. Additionally, a variety of 2-oxa-2-alkyl 3,4-dihydro 2,1-benzothiazines are synthesized via intramolecular metal­-catalyzed N-arylation of appropriately functionalized sulfoximines with tethered 2-bromoaryl substituents. In turn, the sulfoximines are prepared by lithiation-alkylation sequences including enantioselective deprotonation steps or the use of an optically active sulfoxide. Using this methodology, the range of accessible 3,4-dihydro 2,1-benzothiazine derivatives is expanded.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArtic... Synthesis journals http://www.medworm.com/rss/comments.php?id=5330070 Mon, 17 Oct 2011 04:00:00 +0100 5330070 Michael Addition of Various Nitrogen and Oxygen Nucleophiles to 1,1-Diethoxybut-3-yn-2-one http://www.medworm.com/index.php?rid=5330069&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0031-1289294 SynthesisDOI: 10.1055/s-0031-1289294Abstract1,1-Diethoxybut-3-yn-2-one, a conjugated terminal acetylenic ketone, reacts with nitrogen and oxygen nucleophiles and gives Michael adducts, in most cases in good to excellent yield. In almost every case the predominant reaction is monoaddition, which leads to formation of the corresponding β-substituted α,β-unsaturated ketones in a stereospecific fashion. The stereochemistry depends on the nature of the nucleophile, the general pattern being that ammonia and primary amines give Z-alkenones, whereas secondary amines and alcohols afford E-alkenones. Triethylamine does not furnish a Michael addition product, but catalyzes a trimerization that leads to formation of a 6H-1,3-dioxine derivative. When bis-nucleophiles, for instance hydrazine and hyd... Synthesis journals http://www.medworm.com/rss/comments.php?id=5330069 Mon, 17 Oct 2011 04:00:00 +0100 5330069 Thiohydantoins: Selective N- and S-Functionalization for Liebeskind-Srogl Reaction Study http://www.medworm.com/index.php?rid=5310368&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0030-1260259 SynthesisDOI: 10.1055/s-0030-1260259AbstractThiohydantoins formed by the Schlack-Kumpf protocol were selectively functionalized at the nitrogen, sulfur, or carbon atom to test the Liebeskind-Srogl reaction possibilities.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5310368 Mon, 10 Oct 2011 04:00:00 +0100 5310368 Practical Preparation Methods for Highly Active Azaadamantane-Nitroxyl-Radical-Type Oxidation Catalysts http://www.medworm.com/index.php?rid=5301484&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0030-1260257 SynthesisDOI: 10.1055/s-0030-1260257AbstractWe have recently disclosed that a less hindered class of nitroxyl radicals, i.e., 2-azaadamantan-N-oxyl (AZADO), 1-Me-AZADO, and 9-azabicyclo[3.3.1]nonan-N-oxyl (ABNO), exhibit marked catalytic activity for the oxidation of alcohols with the aid of environmentally friendly oxidants, offering a green and sustainable option for current alcohol oxidation. Encouraged by their outstanding catalytic performance, we envisioned the development of scalable routes to these radicals that could be extended to the commercialization of these radicals for benchtop use as well as for industrial use as optional reagents that complement TEMPO, the flagship compound of stable nitroxyl radicals. We herein describe short and reproducible preparation methods for AZADO... Synthesis journals http://www.medworm.com/rss/comments.php?id=5301484 Fri, 07 Oct 2011 04:00:00 +0100 5301484 Vitamin D Heterocyclic Analogues; Part 2: Synthesis of the First Vitamin D Analogues with a Tetrazole Ring at the Side Chain http://www.medworm.com/index.php?rid=5301483&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0030-1260258 SynthesisDOI: 10.1055/s-0030-1260258AbstractAccess to the calcitriol analogues with a tetrazole ring at the side chain was very efficiently achieved using the Calverley-Choudhry approach instead of the Wittig-Horner method, which gave very low yields.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5301483 Fri, 07 Oct 2011 04:00:00 +0100 5301483 Mechanistic Studies on a New Catalyst System (CuI-NaHSO4×SiO2) Leading to the One-Pot Synthesis of Imidazo[1,2-a]pyridines from Reactions of 2-Aminopyridines, Aldehydes, and Terminal Alkynes http://www.medworm.com/index.php?rid=5292425&cid=s_36597_59_f&fid=36597&url=http%3A%2F%2Fdx.doi.org%2F10.1055%2Fs-0030-1260255 SynthesisDOI: 10.1055/s-0030-1260255AbstractOne-pot reactions of aldehydes, 2-aminopyridines, and terminal alkynes, in the presence of the copper(I) iodide-NaHSO4Ë™SiO2 combination catalyst in refluxing toluene, generate the corresponding imidazo[1,2-a]pyridines in high to excellent yields; the mechanism has been studied.[...]© Georg Thieme Verlag Stuttgart Ë™ New YorkArticle in Thieme eJournals:Table of contents  |  Abstract  |  Full text (Source: Synthesis) Synthesis journals http://www.medworm.com/rss/comments.php?id=5292425 Thu, 06 Oct 2011 04:00:00 +0100 5292425