Photoredox-Catalyzed Intramolecular Difluoromethylation of<i>N</i>-Benzylacrylamides Coupled with a Dearomatizing Spirocyclization: Access to CF₂H-Containing 2-Azaspiro[4.5]deca-6,9-diene-3,8-diones

Abstract

A visible light-mediated difluoromethylation of N-benzylacrylamides with HCF2SO2Cl as the HCF2 radical precursor is described. The reaction incorporates a tandem cyclization/dearomatization process to afford various difluoromethylated 2-azaspiro[4.5]deca-6,9-diene-3,8-diones bearing adjacent quaternary stereocenters under mild conditions in moderate to excellent yields.