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Photoredox Radical/Polar Crossover Enables Construction of Saturated Nitrogen Heterocycles.

ABSTRACT: Photoredox-mediated radical/polar crossover (RPC) processes offer new avenues for the synthesis of cyclic molecules. This process has been realized for the construction of medium-sized saturated nitrogen heterocycles. Photocatalytically generated alkyl radicals possessing pendant leaving groups engage imines in C-C bond formation, and subsequent reduction of the intermediate nitrogen-centered radical triggers anionic ring closure. With the aid of visible light irradiation, substituted pyrrolidines, piperidines, and azepanes can be prepared under mild, redox-neutral conditions.

SUBMITTER: Pantaine LRE

PROVIDER: S-EPMC6452489 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature

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Photoredox Radical/Polar Crossover Enables Construction of Saturated Nitrogen Heterocycles.

Pantaine Loïc R E LRE Milligan John A JA Matsui Jennifer K JK Kelly Christopher B CB Molander Gary A GA

Organic letters 20190312 7

Photoredox-mediated radical/polar crossover (RPC) processes offer new avenues for the synthesis of cyclic molecules. This process has been realized for the construction of medium-sized saturated nitrogen heterocycles. Photocatalytically generated alkyl radicals possessing pendant leaving groups engage imines in C-C bond formation, and subsequent reduction of the intermediate nitrogen-centered radical triggers anionic ring closure. With the aid of visible light irradiation, substituted pyrrolidin ...[more]

PMID: 30860849

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