Photocatalytic reductive radical–radical coupling of N,N′-cyclicazomethine imines with difluorobromo derivatives

Abstract

A visible-light-induced difluoroalkylation of N,N′-cyclicazomethine imine was successfully realized through a novel photoredox radical–radical cross-coupling reaction. This developed protocol exhibits high functional group tolerance and affords a variety of difluorinated 3-pyrazolidinone scaffolds. Extensive mechanistic investigations have been undertaken, well revealing the involvement of a reductive radical–radical coupling pathway.