Silacarboxylic acid-mediated photoredox Z-stereoselective fluoroalkylation of alkynes

Abstract

The photoredox-catalyzed fluoroalkylation of alkynes has been developed with silacarboxylic acid as an easily accessible, safe, and highly stable novel halogen-atom transfer mediator. The reaction led to the synthesis of cis-monofluoroalkyl alkenes and difluoroalkyl alkenes in good yields with good Z-stereoselectivities. This method features uncomplicated conditions, operational simplicity, broad substrate scope and excellent compatibility with functional groups. It is well applied in the stereoselective late-stage monofluoroalkyl derivatization of complex drug-like molecules. A plausible reaction mechanism is proposed supported by the mechanism study experiments and in-depth DFT study.