Cobalt-Mediated Photochemical C-H Arylation of Pyrroles
We present herein the scope of this C-H arylation protocol and provide mechanistic insights derived from detailed spectroscopic and computational studies. These indicate that, despite its transient existence, reduction of *[1‑Co]2+ is facilitated via pre-assembly with the NEt3 reductant, highlighting an alternative strategy for the future development of 3d metal-catalyzed PRC.PMID:38693673 | DOI:10.1002/anie.202405780 (Source: Angewandte Chemie)
Source: Angewandte Chemie - May 2, 2024 Category: Chemistry Authors: Julia M ärsch Sebastian Reiter Thomas Rittner Rafael E Rodriguez-Lugo Maximilian Whitfield Daniel J Scott Roger Jan Kutta Patrick Nuernberger Regina de Vivie-Riedle Robert Wolf Source Type: research
Ligand Isomerization Driven Electrocatalytic Switching
Angew Chem Int Ed Engl. 2024 May 2:e202405664. doi: 10.1002/anie.202405664. Online ahead of print.ABSTRACTThe prevailing view about molecular catalysts is that the central metal ion is responsible for the reaction mechanism and selectivity, whereas the ligands mainly affect the reaction kinetics. Here, we question this paradigm and show that ligands have a dramatic influence on the selectivity of the product. We show how even a seemingly small change in ligand isomerization sharply alters the selectivity of the well-researched oxygen reduction reaction (ORR) Co phthalocyanine catalyst from an indirect 2e- to a direct 4e- p...
Source: Angewandte Chemie - May 2, 2024 Category: Chemistry Authors: Alagar Raja Kottaichamy Mohammed Azeezulla Nazrulla Muskan Parmar Ravikumar Thimmappa Mruthyunjayachari Chattanahalli Devendrachari Chathakudath Prabhakaran Vinod Michael Volokh Harish Makri Nimbegondi Kotresh Menny Shalom Musthafa Ottakam Thotiyl Source Type: research
Kinase Inhibition via Small Molecule-Induced Intramolecular Protein Cross-Linking
Angew Chem Int Ed Engl. 2024 May 2:e202404195. doi: 10.1002/anie.202404195. Online ahead of print.ABSTRACTRemarkable progress has been made in the development of cysteine-targeted covalent inhibitors. In kinase drug discovery, covalent inhibitors capable of targeting other nucleophilic residues (i.e. lysine, or K) has emerged in recent years. Besides a highly conserved catalytic lysine, almost all human protein kinases possess an equally conserved glutamate/aspartate (e.g. E/D) that forms a K-E/D salt bridge within the enzyme active-site. Electrophilic ynamides were previously used as effective peptide coupling reagents an...
Source: Angewandte Chemie - May 2, 2024 Category: Chemistry Authors: Xuan Wang Jie Sun Huisi Huang Guanghui Tang Peng Chen Menghua Xiang Lin Li Zhi-Min Zhang Liqian Gao Shao Q Yao Source Type: research
[2+1] Cycloadditions Modulate the Hydrophobicity of Ni-N4 Single-Atom Catalysts for Efficient CO2 Electroreduction
Angew Chem Int Ed Engl. 2024 May 2:e202405650. doi: 10.1002/anie.202405650. Online ahead of print.ABSTRACTMicroenvironment regulation of M-N4 single-atom catalysts (SACs) is a promising way to tune their catalytic properties toward the electrochemical CO2 reduction reaction. However, strategies that can effectively introduce functional groups around the M-N4 sites through strong covalent bonding and under mild reaction conditions are highly desired. Taking the hydrophilic Ni-N4 SAC as a representative, we report herein a [2+1] cycloaddition reaction between Ni-N4 and in-situ generated difluorocarbene (F2C:), and enable the...
Source: Angewandte Chemie - May 2, 2024 Category: Chemistry Authors: Siyan Shu Tao Song Cheng Wang Hao Dai Lele Duan Source Type: research
A Stable Chichibabin Diradicaloid with Near-Infrared Emission
Angew Chem Int Ed Engl. 2024 May 2:e202404853. doi: 10.1002/anie.202404853. Online ahead of print.ABSTRACTConjugated molecules with multiple radical centers such as the iconic Chichibabin diradicaloid hold promise as building blocks in materials for quantum sensing and quantum information processing. However, it is a considerable challenge to design simple analogues of the Chichibabin hydrocarbon that are chemically inert, exhibit high diradical character and emit light at a distinct wavelength that may offer an optical readout of the spin state in functional ensembles. Here we describe the serendipitous discovery of the s...
Source: Angewandte Chemie - May 2, 2024 Category: Chemistry Authors: Xingmao Chang Mona E Arnold R émi Blinder Julia Zolg Jonathan Wischnat Joris van Slageren Fedor Jelezko Alexander J C Kuehne Max von Delius Source Type: research
Intermolecular Enantioselective Amination Reactions Mediated by Visible Light and a Chiral Iron Porphyrin Complex
Angew Chem Int Ed Engl. 2024 May 2:e202407003. doi: 10.1002/anie.202407003. Online ahead of print.ABSTRACTIn the presence of 1 mol% of a chiral iron porphyrin catalyst, various 3-arylmethyl-substituted 2-quinolones and 2-pyridones underwent an enantioselective amination reaction (20 examples; 93-99% ee). The substrates were used as the limiting reagents, and fluorinated aryl azides (1.5 equiv.) served as nitrene precursors. The reaction is triggered by visible light which allows a facile dediazotation at ambient temperature. The selectivity of the reaction is governed by a two-point hydrogen bond interaction between the li...
Source: Angewandte Chemie - May 2, 2024 Category: Chemistry Authors: Hussayn Ahmed Biki Ghosh Stefan Breitenlechner Malte Fe ßner Christian Merten Thorsten Bach Source Type: research
Alkene 1,3-Difluorination via Transient Oxonium Intermediates
Angew Chem Int Ed Engl. 2024 May 2:e202404666. doi: 10.1002/anie.202404666. Online ahead of print.ABSTRACTThe 1,3-difunctionalization of unactivated alkenes is an under-explored transformation that leads to moieties that are otherwise challenging to prepare. Herein, we report a hypervalent iodine-mediated 1,3-difluorination of homoallylic (aryl) ethers to give unreported 1,3-difluoro-4-oxy groups with moderate to excellent diastereoselectivity. The transformation proceeds through a different mode of reactivity for 1,3-difunctionalization, in which a regioselective addition of fluoride opens a transiently formed oxonium int...
Source: Angewandte Chemie - May 2, 2024 Category: Chemistry Authors: Alice C Dean E Harvey Randle Andrew J D Lacey Guiherme A Marczak Giorio Sayad Doobary Benjamin D Cons Alastair Lennox Source Type: research
Correspondence on "Organo-Mediator Enabled Electrochemical Deuteration of Styrenes"
Angew Chem Int Ed Engl. 2024 May 2:e202316037. doi: 10.1002/anie.202316037. Online ahead of print.ABSTRACTThe recently reported electrochemical, organo-mediator enabled deuteration of styrenes, a reaction referred to as "electrochemical deuterium atom transfer", differs mechanistically from reported direct electrochemical hydrogenations/deuterations only by a mediated, homogeneous SET to the substrates. By comparing direct vs. mediated processes in general and for styrene reduction, we display that Qiu's work does not change the concept of this chemistry. Experiments with mediators and the direct reduction of examples from...
Source: Angewandte Chemie - May 2, 2024 Category: Chemistry Authors: Simon Kolb Daniel B Werz Source Type: research
Gold-Catalysed Heck Reaction: Fact or Fiction? Correspondence on "Unlocking the Chain Walking Process in Gold Catalysis"
Angew Chem Int Ed Engl. 2024 May 2:e202317774. doi: 10.1002/anie.202317774. Online ahead of print.ABSTRACTTwo recent high-profile publications reported the formation of Heck-type arylated alkenes catalysed by MeDalPhosAuCl/AgOTf (J. Am. Chem. Soc. 2023, 145, 8810) and their cyclisation to tetralines (Angew. Chem. Int. Ed. 2023, e202312786). It was claimed that these were the first demonstrations in gold catalysis of alkene insertion into Au-aryl bonds, β-H elimination and chain-walking by Au-H dications. We show here that in fact this chemistry is a two-stage process. Only the first step, the production of an alkyl trifla...
Source: Angewandte Chemie - May 2, 2024 Category: Chemistry Authors: Peter H M Budzelaar Manfred Bochmann Martina Landrini Luca Rocchigiani Source Type: research
Pyridinium-Yne Click Polymerization: A Facile Strategy toward Functional Poly(Vinylpyridinium Salt)s with Multidrug-Resistant Bacteria Killing Ability
In this study, we demonstrate a simple and efficient strategy for synthesizing functional poly(vinylpyridinium salt)s via pyridinium-yne click polymerization. This click polymerization could proceed with high atom economy under mild conditions without any external catalyst, yielding soluble and thermally stable poly(vinylpyridinium salt)s with satisfactory molecular weights and well-defined structures in excellent yields. Additionally, the incorporation of luminescent units such as fluorene, tetraphenylethylene, and triphenylamine into the polymer backbone confers excellent aggregation-enhanced emission properties upon the...
Source: Angewandte Chemie - May 2, 2024 Category: Chemistry Authors: Benzhao He Ying Li Meng Li Miaomiao Kang Xinyue Liu Jiachang Huang Dong Wang Jacky W Y Lam Ben Zhong Tang Source Type: research
Electrocatalytic Formal C(sp2)-H Alkylations via Nickel-Catalyzed Cross-Electrophile Coupling with Versatile Arylsulfonium Salts
Angew Chem Int Ed Engl. 2024 May 2:e202401198. doi: 10.1002/anie.202401198. Online ahead of print.ABSTRACTProducing sp3-hybridized carbon-enriched molecules is of particular interest due to their high success rate in clinical trials. The installation of aliphatic chains onto aromatic scaffolds was accomplished by nickel-catalyzed C(sp2)-C(sp3) cross-electrophile coupling with arylsulfonium salts. Thus, simple non-prefunctionalized arenes could be alkylated through the formation of aryldibenzothiophenium salts. The reaction employs an electrochemical approach to avoid potentially hazardous chemical redox agents, and importa...
Source: Angewandte Chemie - May 2, 2024 Category: Chemistry Authors: Takuya Michiyuki Simon L Hom ölle Neeraj Kumar Pandit Lutz Ackermann Source Type: research
Solvation Properties of Neutral Gold Species in Supercritical Water Studied By THz Spectroscopy
Angew Chem Int Ed Engl. 2024 May 2:e202402120. doi: 10.1002/anie.202402120. Online ahead of print.ABSTRACTSupercritical water provides distinctly different solvation properties compared to what is known from liquid water. Despite its prevalence deep in the Earth's crust and its role in chemosynthetic ecosystems in the vicinity of hydrothermal vents, molecular insights into its solvation mechanisms are still very scarce compared to what is known for liquid water. Recently, neutral metal particles have been detected in hydrothermal fluids and proposed to explain the transport of gold species to ore deposits on Earth. Using a...
Source: Angewandte Chemie - May 2, 2024 Category: Chemistry Authors: Jan Noetzel Philipp Schienbein Harald Forbert Dominik Marx Source Type: research
Total Synthesis of Lissodendoric Acid A
We describe a full account of our synthetic strategy leading to the first total synthesis of the manzamine alkaloid lissodendoric acid A . These efforts demonstrate that strained cyclic allenes are valuable synthetic building blocks and can be employed efficiently in total synthesis.PMID:38695853 | DOI:10.1002/anie.202406676 (Source: Angewandte Chemie)
Source: Angewandte Chemie - May 2, 2024 Category: Chemistry Authors: Francesca M Ippoliti Laura G Wonilowicz Nathan J Adamson Evan R Darzi Joyann S Donaldson Daniel J Nasrallah Milauni M Mehta Andrew V Kelleghan K N Houk Neil K Garg Source Type: research
Stabilizing Few-Atom Platinum Clusters by Zinc Single-Atom-Glue for Efficient Anti-Markovnikov Alkene Hydrosilylation
Angew Chem Int Ed Engl. 2024 May 2:e202404568. doi: 10.1002/anie.202404568. Online ahead of print.ABSTRACTFew-atom metal clusters (FAMCs) exhibit superior performance in catalyzing complex molecular transformations due to their special spatial environments and electronic states, compared to single-atom catalysts (SACs). However, achieving the efficient and accurate synthesis of FAMCs while avoiding the formation of other species, such as nanoparticles and SACs, still remains challenges. Herein, we report a two-step strategy for synthesis of few-atom platinum (Pt) clusters by predeposition of zinc single-atom-glue (Zn1) on ...
Source: Angewandte Chemie - May 2, 2024 Category: Chemistry Authors: Ruilong Li Ge Yu Ze Lin Xingen Lin Junyi Du Xiaoping Gao Chenliang Su Yuen Wu Source Type: research
Zeolitic Imidazolate Frameworks as Solid-State Nanomachines
Angew Chem Int Ed Engl. 2024 May 2:e202404061. doi: 10.1002/anie.202404061. Online ahead of print.ABSTRACTMachines have continually developed with the needs of daily life and industrial applications. While the careful design of molecular-scale devices often displays enhanced properties along with mechanical movements, controlling mechanics within solid-state molecular structures remains a significant challenge. Here, we explore the distinct mechanical properties of zeolitic imidazolate frameworks (ZIFs) - frameworks that contain hidden mechanical components. Using a combination of experimental and theoretical approaches, w...
Source: Angewandte Chemie - May 2, 2024 Category: Chemistry Authors: Joohan Nam Seokjin Kim Eunji Jin Soochan Lee Hye Jin Cho Seung Kyu Min Wonyoung Choe Source Type: research
