Photoredox-Catalyzed C–H Functionalization Reactions

Chemical Reviews, Год журнала: 2021, Номер 122(2), С. 1925 - 2016

Опубликована: Сен. 29, 2021

The fields of C–H functionalization and photoredox catalysis have garnered enormous interest utility in the past several decades. Many different scientific disciplines relied on strategies including natural product synthesis, drug discovery, radiolabeling, bioconjugation, materials, fine chemical synthesis. In this Review, we highlight use reactions. We separate review into inorganic/organometallic catalysts organic-based catalytic systems. Further subdivision by reaction class─either sp2 or sp3 functionalization─lends perspective tactical for these methods synthetic applications.

Язык: Английский

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Photons or Electrons? A Critical Comparison of Electrochemistry and Photoredox Catalysis for Organic Synthesis

Chemical Reviews, Год журнала: 2021, Номер 122(2), С. 2487 - 2649

Опубликована: Ноя. 9, 2021

Redox processes are at the heart of synthetic methods that rely on either electrochemistry or photoredox catalysis, but how do and catalysis compare? Both approaches provide access to high energy intermediates (e.g., radicals) enable bond formations not constrained by rules ionic 2 electron (e) mechanisms. Instead, they 1e mechanisms capable bypassing electronic steric limitations protecting group requirements, thus enabling chemists disconnect molecules in new different ways. However, while providing similar intermediates, differ several physical chemistry principles. Understanding those differences can be key designing transformations forging disconnections. This review aims highlight these similarities between comparing their underlying principles describing impact electrochemical photochemical methods.

Язык: Английский

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Photocatalytic Late-Stage C–H Functionalization

Chemical Reviews, Год журнала: 2023, Номер 123(8), С. 4237 - 4352

Опубликована: Янв. 24, 2023

The emergence of modern photocatalysis, characterized by mildness and selectivity, has significantly spurred innovative late-stage C–H functionalization approaches that make use low energy photons as a controllable source. Compared to traditional strategies, photocatalysis paves the way toward complementary and/or previously unattainable regio- chemoselectivities. Merging compelling benefits with workflow offers potentially unmatched arsenal tackle drug development campaigns beyond. This Review highlights photocatalytic strategies small-molecule drugs, agrochemicals, natural products, classified according targeted bond newly formed one. Emphasis is devoted identifying, describing, comparing main mechanistic scenarios. draws critical comparison between established ionic chemistry photocatalyzed radical-based manifolds. aims establish current state-of-the-art illustrate key unsolved challenges be addressed in future. authors aim introduce general readership functionalization, specialist practitioners evaluation methodologies, potential for improvement, future uncharted directions.

Язык: Английский

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Photoinduced intermolecular hydrogen atom transfer reactions in organic synthesis

Chem Catalysis, Год журнала: 2021, Номер 1(3), С. 523 - 598

Опубликована: Май 24, 2021

Язык: Английский

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Alkoxy Radicals See the Light: New Paradigms of Photochemical Synthesis

Chemical Reviews, Год журнала: 2021, Номер 122(2), С. 2429 - 2486

Опубликована: Окт. 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.

Язык: Английский

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Visible‐Light‐Induced Homolysis of Earth‐Abundant Metal‐Substrate Complexes: A Complementary Activation Strategy in Photoredox Catalysis

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(39), С. 21100 - 21115

Опубликована: Фев. 18, 2021

Abstract The mainstream applications of visible‐light photoredox catalysis predominately involve outer‐sphere single‐electron transfer (SET) or energy (EnT) processes precious metal Ru II Ir III complexes organic dyes with low photostability. Earth‐abundant metal‐based M n L ‐type (M=metal, =polydentate ligands) are rapidly evolving as alternative photocatalysts they offer not only economic and ecological advantages but also access to the complementary inner‐sphere mechanistic modes, thereby transcending their inherent limitations ultrashort excited‐state lifetimes for use effective photocatalysts. generic process, termed visible‐light‐induced homolysis (VLIH), entails formation suitable light‐absorbing ligated metal–substrate (M ‐Z; Z=substrate) that can undergo homolytic cleavage generate n−1 Z . further transformations.

Язык: Английский

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Copper Catalyzed C(sp³)–H Bond Alkylation via Photoinduced Ligand-to-Metal Charge Transfer

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(7), С. 2729 - 2735

Опубликована: Фев. 12, 2021

Utilizing catalytic CuCl2 we report the functionalization of numerous feedstock chemicals via coupling unactivated C(sp3)-H bonds with electron-deficient olefins. The active cuprate catalyst undergoes Ligand-to-Metal Charge Transfer (LMCT) to enable generation a chlorine radical which acts as powerful hydrogen atom transfer reagent capable abstracting strong electron-rich bonds. Of note is that chlorocuprate an exceedingly mild oxidant (0.5 V vs SCE) and proposed protodemetalation mechanism offers broad scope olefins, offering high diastereoselectivity in case endocyclic alkenes. Cu reduction through LMCT enables highly HAT operationally simple economical protocol.

Язык: Английский

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Photocatalytic C–H activation and the subtle role of chlorine radical complexation in reactivity

Science, Год журнала: 2021, Номер 372(6544), С. 847 - 852

Опубликована: Май 21, 2021

A complex role for chlorine radicals Radicals are atoms or molecules that highly reactive because they have an unpaired electron. common means of investigating whether involved in a particular reaction is to try trap them with acceptor compound. Yang et al. reinvestigated photoinduced alkane oxidation which trapping study had previously implicated alkoxy radicals. Their spectroscopic, kinetic, and isotopic labeling studies revealed chlorine, rather than alkoxy, was the key radical intermediate; prior results stemmed from its complexation alcohols. Science , abd8408, this issue p. 847

Язык: Английский

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Recent Advances in Photoredox‐Mediated Radical Conjugate Addition Reactions: An Expanding Toolkit for the Giese Reaction

Angewandte Chemie International Edition, Год журнала: 2021, Номер 60(39), С. 21116 - 21149

Опубликована: Фев. 25, 2021

Abstract Photomediated Giese reactions are at the forefront of radical chemistry, much like classical tin‐mediated were nearly forty years ago. With global recognition organometallic photocatalysts for mild and tunable generation carbon‐centered radicals, chemists have developed a torrent strategies to form previously inaccessible intermediates that capable engaging in intermolecular conjugate addition reactions. This Review summarizes advances photoredox‐mediated since 2013, with focus on breadth methods provide access crucial can engage processes.

Язык: Английский

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Radical C(sp3)–H functionalization and cross-coupling reactions

Nature Reviews Chemistry, Год журнала: 2022, Номер 6(6), С. 405 - 427

Опубликована: Май 17, 2022

Язык: Английский

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