Unprecedented single-electron-transfer reduction-based N → C acyl migration reactions of imides enabled by redox-neutral photocatalysis

Abstract

Herein, we report new redox-neutral photoredox-catalyzed acyl migration reactions based on a reductive radical-polar crossover process for the first time. Using alkyl silicates as radical precursors, a range of enamides bearing various functional groups are shown to be effective radical acceptors for these transformations. Under mild photocatalytic conditions, various α-amino ketones were efficiently prepared, which are precursors of primary α-tertiary amines. Mechanistic studies suggest that a radical addition/single-electron-transfer reduction/acyl migration cascade process was involved. This novel SET reduction-based acyl migration reaction features base-, additive-, and exogenous reductant-free conditions.