Merging Photoredox and Copper Catalysis: Enantioselective Radical Cyanoalkylation of Styrenes

A photoredox and copper catalyzed asymmetric cyanoalkylation reaction of alkenes has been developed, which uses alkyl N-hydroxyphthalimide esters as alkylation reagents. In this radical cyanoalkylation reaction, the photoredox induced alkyl radical adds to styrene, and the generated benzylic radical couples with a chiral Box/CuII cyanide complex to achieve the enantioselective cyanation. This reaction features mild conditions, operational simplicity, broad substrate scope, high yields, and high enantioselectivities, which represents an efficient method for the asymmetric radical difunctionalization of alkenes.