Electrochemical Late-Stage Functionalization

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(19), P. 11269 - 11335

Published: Sept. 26, 2023

Late-stage functionalization (LSF) constitutes a powerful strategy for the assembly or diversification of novel molecular entities with improved physicochemical biological activities. LSF can thus greatly accelerate development medicinally relevant compounds, crop protecting agents, and functional materials. Electrochemical synthesis has emerged as an environmentally friendly platform transformation organic compounds. Over past decade, electrochemical late-stage (eLSF) gained major momentum, which is summarized herein up to February 2023.

Language: Английский

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Photoelectrochemical Asymmetric Catalysis Enables Direct and Enantioselective Decarboxylative Cyanation

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(44), P. 20201 - 20206

Published: Oct. 31, 2022

The development of efficient and sustainable methods for decarboxylative transformations is great importance due to the ease availability nontoxicity carboxylic acids. Despite tremendous efforts in this area, it remains challenging develop enantioselective direct from Herein we disclose a photoelectrocatalytic method cyanation. photoelectrochemical reactions convert acids enantioenriched nitriles by employing cerium/copper relay catalysis with cerium salt catalytic decarboxylation chiral copper complex stereoselective C-CN formation.

Language: Английский

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Electrophotochemical Ce-Catalyzed Ring-Opening Functionalization of Cycloalkanols under Redox-Neutral Conditions: Scope and Mechanism

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(30), P. 13895 - 13902

Published: July 21, 2022

Selective cleavage and functionalization of C–C bonds in alcohols is gaining increasing interest organic synthesis biomass conversion. In particular, the development redox-neutral catalytic methods with cheap catalysts clean energy utmost interest. this work, we report a versatile method for ring-opening cycloalkanols by electrophotochemical (EPC) cerium (Ce) catalysis. The EPC-Ce-enabled catalysis allows different ring sizes to be cleaved while tolerating broad range functional groups. Notably, presence chloride as counteranion electrolyte, protocol selectively leads formation C–CN, C–C, C–S, or C–oxime instead C–halide bond after β-scission. A preliminary mechanistic investigation indicates that redox-active Ce catalyst can tuned electro-oxidation photo-reduction, thus avoiding use an external oxidant. Spectroscopic characterizations (cyclic voltammetry, UV–vis, electron paramagnetic resonance, X-ray absorption fine structure) suggest Ce(III)/Ce(IV) pathway transformation, which Ce(IV)-alkoxide involved.

Language: Английский

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Identification of Alkoxy Radicals as Hydrogen Atom Transfer Agents in Ce-Catalyzed C–H Functionalization

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 145(1), P. 359 - 376

Published: Dec. 20, 2022

The intermediacy of alkoxy radicals in cerium-catalyzed C–H functionalization via H-atom abstraction has been unambiguously confirmed. Catalytically relevant Ce(IV)–alkoxide complexes have synthesized and characterized by X-ray diffraction. Operando electron paramagnetic resonance transient absorption spectroscopy experiments on isolated pentachloro Ce(IV) alkoxides identified as the sole heteroatom-centered radical species generated ligand-to-metal charge transfer (LMCT) excitation. Alkoxy-radical-mediated hydrogen atom (HAT) verified kinetic analysis, density functional theory (DFT) calculations, reactions under strictly chloride-free conditions. These experimental findings establish critical role Ce-LMCT catalysis definitively preclude involvement chlorine radical. This study also reinforced necessity a high relative ratio alcohol vs Ce for selective alkoxy-radical-mediated HAT, seemingly trivial changes can lead to drastically different mechanistic pathways. Importantly, previously proposed radical–alcohol complex, postulated explain alkoxy-radical-enabled selectivities this system, examined scrutiny ruled out regioselectivity studies, experiments, high-level calculations. Moreover, peculiar selectivity generation LMCT homolysis heteroleptic analyzed back-electron (BET) may regulated efficiency formation ligand-centered radicals.

Language: Английский

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Resurgence and advancement of photochemical hydrogen atom transfer processes in selective alkane functionalizations

Chemical Science, Journal Year: 2023, Volume and Issue: 14(25), P. 6841 - 6859

Published: Jan. 1, 2023

The selective functionalization of alkanes has long been recognized as a prominent challenge and an arduous task in organic synthesis. Hydrogen atom transfer (HAT) processes enable the direct generation reactive alkyl radicals from feedstock have successfully employed industrial applications such methane chlorination process,

Language: Английский

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Photoelectrochemical Asymmetric Catalysis Enables Enantioselective Heteroarylcyanation of Alkenes via C–H Functionalization

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(34), P. 18753 - 18759

Published: Aug. 15, 2023

The asymmetric difunctionalization of alkenes, a method transforming readily accessible alkenes into enantioenriched chiral structures high value, has long been focal point organic synthesis. Despite tremendous efforts in this domain, it remains considerable challenge to devise enantioselective oxidative dicarbofunctionalization even though these transformations can utilize stable and unfunctionalized functional group donors. In context, we report herein photoelectrocatalytic for the heteroarylcyanation aryl which employs heteroarenes through C-H functionalization. photoelectrochemical catalysis (PEAC) combines photoredox electrocatalysis facilitate formation two C-C bonds operating via hydrogen (H2) evolution obviating need external chemical oxidants.

Language: Английский

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Electrochemical radical-polar crossover: a radical approach to polar chemistry

Science China Chemistry, Journal Year: 2023, Volume and Issue: 67(2), P. 450 - 470

Published: Nov. 3, 2023

Language: Английский

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Paired Oxidative and Reductive Catalysis: Breaking the Potential Barrier of Electrochemical C(sp³)−H Alkenylation**

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(24)

Published: April 1, 2023

Due to the intrinsic inertness of alkanes, strong oxidative conditions are typically required enable their C(sp3 )-H functionalization. Herein, a paired electrocatalysis strategy was developed by integrating catalysis with reductive in one cell without interference, which earth-abundant iron and nickel employed as anodic cathodic catalysts, respectively. This approach lowers previously high oxidation potential for alkane activation, enabling electrochemical functionalization at ultra-low ≈0.25 V vs. Ag/AgCl under mild conditions. Structurally diverse alkenes, including challenging all-carbon tetrasubstituted olefins, can be accessed using readily available alkenyl electrophiles.

Language: Английский

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Organophotoelectrocatalytic C(sp²)–H alkylation of heteroarenes with unactivated C(sp³)–H compounds

Chemical Communications, Journal Year: 2024, Volume and Issue: 60(42), P. 5502 - 5505

Published: Jan. 1, 2024

An organophotoelectrocatalytic method for the C(sp 2 )–H alkylation of heteroarenes with unactivated 3 compounds via dehydrogenation cross-coupling was developed.

Language: Английский

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Photoelectrochemically driven iron-catalysed C(sp3)−H borylation of alkanes

Nature Synthesis, Journal Year: 2024, Volume and Issue: 3(4), P. 537 - 544

Published: Jan. 31, 2024

Language: Английский

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