Alkoxy Radicals See the Light: New Paradigms of Photochemical Synthesis

Chemical Reviews, Journal Year: 2021, Volume and Issue: 122(2), P. 2429 - 2486

Published: Oct. 6, 2021

Alkoxy radicals are highly reactive species that have long been recognized as versatile intermediates in organic synthesis. However, their development has impeded due to a lack of convenient methods for generation. Thanks advances photoredox catalysis, enabling facile access alkoxy from bench-stable precursors and free alcohols under mild conditions, research interest this field renewed. This review comprehensively summarizes the recent progress radical-mediated transformations visible light irradiation. Elementary steps radical generation either or central reaction development; thus, each section is categorized discussed accordingly. Throughout review, we focused on different mechanisms well impact synthetic utilizations. Notably, catalytic abundant still early stage, providing intriguing opportunities exploit diverse paradigms.

Language: Английский

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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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Organoelectrophotocatalytic C–H Silylation of Heteroarenes

Organic Letters, Journal Year: 2023, Volume and Issue: 25(6), P. 1008 - 1013

Published: Feb. 3, 2023

An organoelectrophotocatalytic approach for the C-H silylation of heteroarenes through dehydrogenation cross-coupling with H2 evolution has been developed. The strategy is carried out under a simple and efficient monocatalytic system by employing 9,10-phenanthrenequinone both as an organocatalyst hydrogen atom transfer (HAT) reagent, which avoids need external HAT oxidant, or metal reagent. A variety can be compatible in satisfactory yields excellent regioselectivity.

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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Organoelectrophotocatalytic Generation of Acyl Radicals from Formamides and Aldehydes: Access to Acylated 3-CF₃-2-Oxindoles

Organic Letters, Journal Year: 2023, Volume and Issue: 25(38), P. 7014 - 7019

Published: Sept. 18, 2023

Organoelectrophotocatalytic generation of acyl radicals from formamides and aldehydes to synthesize acylated 3-CF3-2-oxindoles has been developed. This protocol features a monocatalytic system using 9,10-phenanthrenequinone (PQ) both as catalyst hydrogen atom transfer (HAT) reagent, which avoids the use an external HAT metal oxidant. A variety have obtained in satisfactory yields CF3-substituted N-arylacrylamides via tandem radical cyclization.

Language: Английский

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Electrochemically Driven Hydrogen Atom Transfer Catalysis: A Tool for C(sp³)/Si–H Functionalization and Hydrofunctionalization of Alkenes

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(13), P. 8731 - 8751

Published: June 16, 2023

Electrochemically driven hydrogen atom transfer (HAT) catalysis provides a complementary approach for the transformation of redox-inactive substrates that would be inaccessible to conventional electron (ET) catalysis. Moreover, electrochemically HAT could promote organic transformations with either abstraction or donation as key step. It versatile and effective tool direct functionalization C(sp3)–H/Si–H bonds hydrofunctionalization alkenes. Despite these attractive properties, has been largely overlooked due lack understanding both catalytic mechanism how catalyst selection should occur. In this Review, we give an overview applications in The mechanistic pathways, physical properties mediators, state-of-the-art examples are described discussed.

Language: Английский

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Organophotoelectrochemical silylation cyclization for the synthesis of silylated 3-CF₃-2-oxindoles

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(14), P. 3585 - 3590

Published: Jan. 1, 2023

An organophotoelectrochemical approach for silylation cyclization of CF3-substituted N -arylacrylamides with organosilanes under transition-metal-free and oxidant-free conditions has been developed.

Language: Английский

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