Catalytic Photoredox Carbobromination of Unactivated Alkenes with α-Bromocarbonyls via the Mechanistically Distinct Radical-Addition Radical-Pairing Pathway.

ABSTRACT: We disclose a catalytic photoredox carbobromination of unactivated alkenes with α-bromocarbonyl compounds under a blue LED light. The reaction proceeds with α-bromoesters, α-bromonitriles and α-bromo-γ-lactones along with terminal and 1,2-disubstituted internal alkenes. Reactions with indenes and 1,1-disubstituted alkenes generate alkylated alkenes. Mechanistic studies by product selectivity and three-way competitive crossover experiments suggest that the reaction operates by a radical-addition radical-pairing (RARP) mechanism. The catalytic turnover is achieved by a single electron reduction of PC^•+ by Br^- (or Br₃ ^-), rather than by alkyl radical (R•), and the product is generated by the pairing of Br• (or Br₂•^-) and R•, in

SUBMITTER: Singh H 

PROVIDER: S-EPMC11694795 | biostudies-literature | 2024 Apr

REPOSITORIES: biostudies-literature