Photoinduced Electron Donor Acceptor Complex‐Enabled α‐C(sp³)−H Alkenylation of Amines

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(44)

Published: July 13, 2024

Allylic amines are prevalent and vital structural components present in many bioactive compounds natural products. Additionally, they serve as valuable intermediates building blocks, with wide-ranging applications organic synthesis. However, direct α-C(sp

Language: Английский

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Electroreduction strategy: a sustainable tool for the generation of aryl radicals

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(15), P. 4318 - 4342

Published: Jan. 1, 2024

This review primarily focuses on the generation of aryl radicals via an electroreduction strategy, and systematically elaborates synthetic applications, scope, limitations substrates.

Language: Английский

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Visible-light-mediated synthesis of polysubstituted pyrroles via C_Ar–I reduction triggered 1,5-hydrogen atom transfer process

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(16), P. 4522 - 4528

Published: Jan. 1, 2024

A novel strategy for the construction of polysubstituted pyrroles has been developed through visible-light-induced single-electron reduction C Ar –I bonds and following 1,5-hydrogen atom transfer (HAT) process.

Language: Английский

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Site-selective α-C(sp3)–H arylation of dialkylamines via hydrogen atom transfer catalysis-enabled radical aryl migration

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: Aug. 8, 2024

Site-selective C(sp3)–H arylation is an appealing strategy to synthesize complex arene structures but remains a challenge facing synthetic chemists. Here we report the use of photoredox-mediated hydrogen atom transfer (HAT) catalysis accomplish site-selective α-C(sp3)–H dialkylamine-derived ureas through 1,4-radical aryl migration, by which wide array benzylamine motifs can be incorporated medicinally relevant systems in late-stage installation steps. In contrast previous efforts, this C–H protocol exhibits specific site-selectivity, proforming predominantly on sterically more-hindered secondary and tertiary α-amino carbon centers, while functionalization less-hindered N-methyl group effectively circumvented most cases. Moreover, diverse range multi-substituted piperidine derivatives obtained with excellent diastereoselectivity. Mechanistic computational studies demonstrate that rate-determining step for methylene initial H abstraction, whereas radical ipso cyclization bears highest energy barrier functionalization. The relatively lower activation free energies compared methylic bond lead exceptional site-selectivity. authors migration.

Language: Английский

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Photoinduced Copper-Catalyzed Regio- and Diastereoselective Multicomponent [3 + 2 + 1] Radical Cyclization To Access Tetrahydropyridines

Organic Letters, Journal Year: 2025, Volume and Issue: unknown

Published: May 12, 2025

The use of simple raw materials to construct complex piperidine scaffolds via multicomponent reactions is highly desirable from the perspectives atom and step-economy. In this Letter, we present a photoinduced copper-catalyzed three- or four-component [3 + 2 1] radical cyclization, utilizing inexpensive readily available feedstock amines, alkynes, aldehydes, synthesize multisubstituted bicyclic spirocyclic tetrahydropyridines. This method notable for its mild conditions, atom-economic approach, excellent regio- diastereoselectivity, simultaneous activation two α-amino C(sp3)-H bonds, resulting in formation three C-C bonds one C-N bond single step. Mechanistic studies suggest that α-aminoalkyl key intermediate reaction, which undergoes sequential addition, 1,5-HAT, 6-exo-trig-type cyclization.

Language: Английский

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Photoinduced Remote Selective C(sp³)−H Alkylation Mediated by Cesium Formate

European Journal of Organic Chemistry, Journal Year: 2024, Volume and Issue: 27(32)

Published: May 13, 2024

Abstract Herein, we developed a photoinduced remote selective C( sp 3 )−H alkylation of protected amines in the presence cesium formate. The were synthesized from commercially available inexpensive 2‐iodo benzoyl chloride. Under mild reaction conditions, situ generated aryl radical is converted to α‐amidoalkyl via [1,5]‐HAT process, which combines with different Michael acceptors and affords corresponding products good yields. Preliminary mechanistic studies revealed that formate anion acts as source carbon dioxide (CO 2 ⋅ − ) hydrogen atom donor was directly confirmed by isotope‐labeling studies.

Language: Английский

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β-Silicon Effect Enables Metal-Free Site-Selective Intermolecular Allylic C–H Amination

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(11), P. 8865 - 8873

Published: May 23, 2024

α-Amino silanes and their derivatives play pivotal roles across diverse applications, yet current synthetic methods often entail intricate functional group manipulations. Despite the widespread use of allyl as carbon nucleophiles in organic synthesis, participation allylic C–H functionalization has been underexplored. Herein, we unveil a metal-free intermolecular amination facilitated by β-silicon effect. This protocol yields α-amino with exceptional site selectivity. Notably, wide array secondary tertiary are synthesized high without desilylation, owing to mild reaction conditions pathway. Mechanistic elucidations highlight activation effect silyl moiety on alkenes, alongside its stabilizing influence adjacent developing positive charges, which selectively drives closed transition state, ensuring

Language: Английский

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Aryl-to-alkyl radical relay arylation reaction of remote C(sp3)-H bond using 1,4-dicyanobenzene as an electrochemical redox-mediator

Organic Chemistry Frontiers, Journal Year: 2024, Volume and Issue: 11(15), P. 4182 - 4186

Published: Jan. 1, 2024

In this paper, we developed an electro-reductive aryl-to-alkyl radical relay arylation reaction of a remote C(sp 3 )–H bond via 1,5-HAT process. This protocol features mild conditions, simple operation, and broad substrate scope.

Language: Английский

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Remote C(sp³)–H Carboxylation with CO₂ via Visible-Light-Catalyzed 1,5-Hydrogen Atom Transfer

Organic Letters, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 13, 2024

The direct carboxylation of C(sp3)–H bonds with CO2 represents a challenging but highly attractive strategy in organic synthesis. In this study, we presented visible-light-catalyzed for carboxylating remote via aryl radical induced 1,5-hydrogen atom transfer. This transformation involves generating alkyl radicals transfer from radicals, forming carbanions as key intermediates, and subsequent nucleophilic attack CO2, thereby enabling access to variety tertiary quaternary carboxylic acids moderate good yields.

Language: Английский

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Photoredox Cross Dehydrogenative C(sp²)-C(sp³) Coupling of Heteroarenes with Secondary Amines through 1,5-HAT

Chemical Communications, Journal Year: 2024, Volume and Issue: 60(72), P. 9757 - 9760

Published: Jan. 1, 2024

The functionalization of α-C(sp

Language: Английский

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