Photocatalytic Late-Stage C–H Functionalization

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(8), P. 4237 - 4352

Published: Jan. 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.

Language: Английский

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Porous organic polymers for light-driven organic transformations

Chemical Society Reviews, Journal Year: 2022, Volume and Issue: 51(7), P. 2444 - 2490

Published: Jan. 1, 2022

As a new generation of porous materials, organic polymers (POPs), have recently emerged as powerful platform heterogeneous photocatalysis. POPs are constructed using extensive synthesis methodologies, with various functional units being connected via high-energy covalent bonds. This review systematically presents the recent advances in for visible-light driven transformations. Herein, we firstly summarize common construction strategies POP-based photocatalysts based on two major approaches: pre-design and post-modification; secondly, categorize methods reaction types constructing POPs. We then classify introduce specific reactions current light-driven POP-mediated Finally, outline state development problems faced transformations by POPs, present some perspectives to motivate reader explore solutions these confront challenges process.

Language: Английский

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Solar Energy Catalysis

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(29)

Published: April 26, 2022

When it comes to using solar energy promote catalytic reactions, photocatalysis technology is the first choice. However, sunlight can not only be directly converted into chemical through a photocatalytic process, also different energy-transfer pathways. Using as source, reactions proceed independently, and coupled with other technologies enhance overall efficiency. Therefore, sunlight-driven are diverse, need given specific definition. We propose timely perspective for driven by give them definition, namely "solar catalysis". The concept of types catalysis, such photocatalysis, photothermal cell powered electrocatalysis, pyroelectric highlighted. Finally, their limitations future research directions discussed.

Language: Английский

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The advent and development of organophotoredox catalysis

Chemical Communications, Journal Year: 2021, Volume and Issue: 58(9), P. 1263 - 1283

Published: Dec. 10, 2021

We herein discuss how and when organic photocatalysts can efficiently replace or outperform their metal counterparts.

Language: Английский

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Aroyl Fluorides as Bifunctional Reagents for Dearomatizing Fluoroaroylation of Benzofurans

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(16), P. 7072 - 7079

Published: March 22, 2022

The 2,3-dihydrobenzofuran scaffold is widely found in natural products and biologically active compounds. Herein, dearomatizing 2,3-fluoroaroylation of benzofurans with aroyl fluorides as bifunctional reagents to access 2,3-difunctionalized dihydrobenzofurans reported. reaction that occurs by cooperative NHC/photoredox catalysis provides 3-aroyl-2-fluoro-2,3-dihydrobenzofurans moderate good yield high diastereoselectivity. Cascades proceed via radical/radical cross-coupling a benzofuran radical cation generated the photoredox cycle neutral ketyl formed through NHC cycle. redox-neutral transformation exhibits broad substrate scope functional group compatibility. With anhydrides reagents, aroyloxyacylation achieved strategy can also be applied

Language: Английский

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Switchable Divergent Synthesis Using Photocatalysis

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(3), P. 1857 - 1878

Published: Jan. 20, 2022

A highly selective and divergent synthesis enables access to various molecules has garnered broad interest from not only organic chemists but also medicinal biologists who work with chemical libraries. Since the 20th century, such transformations have been achieved using transition-metal-catalyzed reactions, in which choice of catalyst or ligand crucially affects selectivity. Over past several decades, photocatalysts attracted a considerable amount attention because they provide additional ways control reaction intermediates product selectivity via electron energy transfer. From this perspective, we highlight recent development switchable syntheses photocatalysts, are difficult achieve classical catalytic transformations.

Language: Английский

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Intercepting Hydrogen Evolution with Hydrogen-Atom Transfer: Electron-Initiated Hydrofunctionalization of Alkenes

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(39), P. 17783 - 17791

Published: Sept. 22, 2022

Hydrogen-atom transfer mediated by earth-abundant transition-metal hydrides (M-Hs) has emerged as a powerful tool in organic synthesis. Current methods to generate M-Hs most frequently rely on oxidatively initiated hydride transfer. Herein, we report reductive approach Co-H, which allows for canonical hydrogen evolution reactions be intercepted hydrogen-atom an alkene. Electroanalytical and spectroscopic studies provided mechanistic insights into the formation reactivity of enabled development two new alkene hydrofunctionalization reactions.

Language: Английский

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Catalytic Asymmetric Construction of Axially and Centrally Chiral Heterobiaryls by Minisci Reaction

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(13), P. 6040 - 6049

Published: March 24, 2022

Axially chiral biaryls and heterobiaryls constitute the most represented subclass of atropisomers with prevalence in natural products, bioactive compounds, privileged ligand/catalysts, optically pure materials. Despite many ionic protocols for their construction, radical-based variants represent another highly desirable intriguing strategy but are far less developed. Moreover, efficient synthesis axially heterobiaryl molecules, especially ones having multiple heteroatoms other types elements, through radical routes remains extremely limited. We herein disclose first catalytic asymmetric, metal-free construction centrally by Minisci reaction 5-arylpyrimidines α-amino acid-derived redox-active esters. This is enabled use 4CzIPN as an organic photoredox catalyst conjunction a phosphoric acid catalyst. The achieved variety interesting featuring union α-branched amine generally excellent regio-, diastereo-, enantioselectivity (up to 82% yield; >19:1 dr; >99% ee). finding also builds up new platform development desymmetrization methods via radical-involved atroposelective functionalization at heteroarene prochiral heterobiaryls.

Language: Английский

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Formation and degradation of strongly reducing cyanoarene-based radical anions towards efficient radical anion-mediated photoredox catalysis

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Jan. 6, 2023

Cyanoarene-based photocatalysts (PCs) have attracted significant interest owing to their superior catalytic performance for radical anion mediated photoredox catalysis. However, the factors affecting formation and degradation of cyanoarene-based PC (PC•‒) are still insufficiently understood. Herein, we therefore investigate PC•‒ under widely-used photoredox-mediated reaction conditions. By screening various PCs, elucidate strategies efficiently generate with adequate excited-state reduction potentials (Ered*) via supra-efficient generation long-lived triplet excited states (T1). To thoroughly behavior in actual reactions, a reductive dehalogenation is carried out as model identified dominant photodegradation pathways PC•‒. Dehalogenation coexistent depending on rate electron transfer (ET) substrate strongly depends electronic steric properties PCs. Based understanding both PC•‒, demonstrate that efficient highly reducing allows catalyzed aryl/alkyl halides at loading low 0.001 mol% high oxygen tolerance. The present work provides new insights into reactions reactions.

Language: Английский

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Photoredox-Enabled Dearomative [2π + 2σ] Cycloaddition of Phenols

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(4), P. 2789 - 2797

Published: Jan. 18, 2024

Dearomative photocycloaddition of monocyclic arenes is an appealing strategy for comprehending the concept "escape from flatland". This brings replacement readily available planar aromatic hydrocarbon units with a 3D fused bicyclic core sp3-enriched carbon units. Herein, we outline intermolecular approach dearomative phenols. In order to circumvent ground-state aromaticity and construct conformationally restrained building blocks, bicyclo[1.1.0]butanes were chosen as coupling partners. renders straightforward access bicyclo[2.1.1]hexane unit cyclic enone moiety, which further contributed synthetic linchpin postmodifications. Mechanistic experiment advocates plausible onset both reactants, depending on redox potential.

Language: Английский

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