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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Synthetic Applications of Sulfonium Salts as Aryl Radical Precursors

European Journal of Organic Chemistry, Год журнала: 2023, Номер 26(43)

Опубликована: Сен. 13, 2023

Abstract The utilization of aryl radicals as open‐shelled intermediates has become an essential tool for both conventional and state‐of‐the‐art synthetic chemistry. However, the current methods generating are still inefficient, greatly impeding their practical applications. Encouragingly, sulfonium salts have emerged appealing sources a wide range transformations aimed at creating novel chemical bonds driven by distinctive structural attributes tendencies. This review primarily focuses on specific reaction mechanisms underlying cleavage C−S in salts, leading to generation corresponding within diverse conditions.

Язык: Английский

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Metal-free, visible-light driven α-C(sp³)–H gem-difluoroallylation of glycine derivatives with trifluoromethyl alkenes and 1,3-enynes

Green Chemistry, Год журнала: 2023, Номер 25(17), С. 6733 - 6738

Опубликована: Янв. 1, 2023

A metal free, visible-light driven α-C(sp 3 )−H gem-difluoroallylation of glycine derivatives with CF -alkenes and 1,3-enynes is presented under redox-neutral conditions good yields excellent functional group compatibility.

Язык: Английский

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Direct Hydrodefluorination of CF₃-Alkenes via a Mild S_N2′ Process Using Rongalite as a Masked Proton Reagent

Organic Letters, Год журнала: 2023, Номер 25(13), С. 2294 - 2299

Опубликована: Март 23, 2023

A concise and efficient hydrodefluorination process was developed for the synthesis of gem-difluoroalkenes. This reaction employs rongalite as a masked proton source does not require any additional catalysts or reductants. Notably, trifluoromethyl alkenes having both terminal internal double bonds are compatible with this process, allowing wider range substrates. The successful late-stage functionalizations pharmaceuticals gram-scale syntheses were used to demonstrate viability method.

Язык: Английский

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Photocatalytic Functionalization of Dehydroalanine‐Derived Peptides in Batch and Flow

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(19)

Опубликована: Март 18, 2024

Abstract Unnatural amino acids, and their synthesis by the late‐stage functionalization (LSF) of peptides, play a crucial role in areas such as drug design discovery. Historically, LSF biomolecules has predominantly utilized traditional synthetic methodologies that exploit nucleophilic residues, cysteine, lysine or tyrosine. Herein, we present photocatalytic hydroarylation process targeting electrophilic residue dehydroalanine (Dha). This possesses an α , β ‐unsaturated moiety can be combined with various arylthianthrenium salts, both batch flow reactors. Notably, setup proved instrumental for efficient scale‐up, paving way unnatural acids peptides substantial quantities. Our approach, being inherently mild, permits diversification even when they contain sensitive functional groups. The readily available salts facilitate seamless integration Dha‐containing wide range arenes, blueprints, natural products, culminating creation unconventional phenylalanine derivatives. synergistic effect high group tolerance modular characteristic aryl electrophile enables peptide conjugation ligation conditions.

Язык: Английский

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Visible light-promoted defluorinative alkylation/arylation of α-trifluoromethyl alkenes with thianthrenium salts

Green Chemistry, Год журнала: 2024, Номер 26(17), С. 9371 - 9377

Опубликована: Янв. 1, 2024

Defluorinative alkylation and arylation between thianthrenium salts α-trifluoromethyl alkene to afford gem -difluoroolefins by easily recycling thianthrene under visible light irradiation free of metal photocatalyst.

Язык: Английский

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Visible-Light-Induced Defluorinative α-C(sp³)–H Alkylation for the Synthesis of gem-Difluoroallylated α-Trifluoromethylamines

Organic Letters, Год журнала: 2023, Номер 25(51), С. 9124 - 9129

Опубликована: Ноя. 17, 2023

Herein, we describe a novel and efficient photoredox catalytic Cα radical addition/defluoroalkylation coupling reaction between α-trifluoromethyl alkenes N-trifluoroethyl hydroxylamine. A series of gem-difluoroallylated α-trifluoromethylamines were synthesized by the addition enabled 1,2-H shift in situ-generated radical. Notably, this protocol is distinguished its mild conditions, easy operation, excellent functional group tolerability.

Язык: Английский

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Energy-transfer-enabled photocatalytic transformations of aryl thianthrenium salts

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Ноя. 8, 2024

Aryl thianthrenium salts are valuable in photocatalysis but traditionally require external electron donors for activation. This study introduces an energy transfer (EnT) strategy the activation of aryl using 2,3,4,5,6-penta(carbazol-9-yl)benzonitrile (5CzBN) as a metal-free photocatalyst, eliminating need donors. Utilizing this EnT approach, we achieve C-H deuteration arenes under visible light with CDCl

Язык: Английский

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Modern photo- and electrochemical approaches to aryl radical generation

Organic Chemistry Frontiers, Год журнала: 2024, Номер 11(18), С. 5232 - 5277

Опубликована: Янв. 1, 2024

This review describes recent advances in the generation of aryl radicals using light and electricity. Such modern techniques allow for efficient energy resource utilization, thus providing more sustainable radical arylation methods.

Язык: Английский

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Transition‐Metal‐Free Allylic Defluorination Cross‐Electrophile Coupling Employing Rongalite

Chinese Journal of Chemistry, Год журнала: 2024, Номер 42(12), С. 1360 - 1366

Опубликована: Фев. 23, 2024

Comprehensive Summary The conversion of CF 3 ‐alkenes to gem ‐difluoroalkenes using reductive cross‐coupling strategy has received much attention in recent years, however, the use green and readily available reducing salt mediate these reactions remains be explored. In this work, a concise construction gem‐ difluoroalkenes, which requires neither catalyst nor metal agent, was established. Rongalite, safe inexpensive industrial product, employed as both radical initiator reductant. This procedure compatible with linear cyclic diaryliodonium salts, enabling wide variety substrates (>70 examples). utility approach demonstrated through gram‐scale synthesis efficient late‐stage functionalizations anti‐inflammatory drugs.

Язык: Английский

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