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Cyclopentene Annulations of Alkene Radical Cations with Vinyl Diazo Species Using Photocatalysis.

ABSTRACT: A direct (3+2) cycloaddition between alkenes and vinyl diazo reagents using either Cr or Ru photocatalysis is described. The intermediacy of a radical cation species enables a nucleophilic interception by vinyl diazo compounds, a departure from their traditional electrophilic behavior. A variety of cyclopentenes are synthesized using this method, and experimental insights implicate a direct cycloaddition instead of a cyclopropanation/rearrangement process.

SUBMITTER: Sarabia FJ

PROVIDER: S-EPMC6319273 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Cyclopentene Annulations of Alkene Radical Cations with Vinyl Diazo Species Using Photocatalysis.

Sarabia Francisco J FJ Li Qiankun Q Ferreira Eric M EM Ferreira Eric M EM

Angewandte Chemie (International ed. in English) 20180720 34

A direct (3+2) cycloaddition between alkenes and vinyl diazo reagents using either Cr or Ru photocatalysis is described. The intermediacy of a radical cation species enables a nucleophilic interception by vinyl diazo compounds, a departure from their traditional electrophilic behavior. A variety of cyclopentenes are synthesized using this method, and experimental insights implicate a direct cycloaddition instead of a cyclopropanation/rearrangement process. ...[more]

PMID: 29964359

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