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Photoredox-Catalyzed Divergent Radical Cascade Annulations of 1,6-Enynes via Pyridine N-Oxide-Promoted Vinyl Radical Generation.

ABSTRACT: The divergent organophotoredox-catalyzed radical cascade annulation reactions of 1,6-enynes were developed. A series of cyclopropane-fused hetero- and carbo-bicyclic, tricyclic, and spiro-tetracyclic compounds were facilely synthesized from a broad scope of 1,6-enynes and 2,6-lutidine N-oxide under mild and metal-free conditions with blue light-emitting diode light irradiation. The cascade annulation reaction occurs with the intermediacy of a β-oxyvinyl radical, which is produced from photocatalytically generated pyridine N-oxy radical addition to the carbon-carbon triple bond.

SUBMITTER: Wang B

PROVIDER: S-EPMC10842598 | biostudies-literature | 2023 Dec

REPOSITORIES: biostudies-literature

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Photoredox-Catalyzed Divergent Radical Cascade Annulations of 1,6-Enynes via Pyridine N-Oxide-Promoted Vinyl Radical Generation.

Wang Ban B Singh Jujhar J Deng Yongming Y

Organic letters 20231219 51

The divergent organophotoredox-catalyzed radical cascade annulation reactions of 1,6-enynes were developed. A series of cyclopropane-fused hetero- and carbo-bicyclic, tricyclic, and spiro-tetracyclic compounds were facilely synthesized from a broad scope of 1,6-enynes and 2,6-lutidine N-oxide under mild and metal-free conditions with blue light-emitting diode light irradiation. The cascade annulation reaction occurs with the intermediacy of a β-oxyvinyl radical, which is produced from pho ...[more]

PMID: 38112553

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