Copper-Catalyzed Asymmetric Cyanation of Alkenes via Carbonyl-Assisted Coupling of Alkyl-Substituted Carbon-Centered Radicals.

Based on a copper-catalyzed radical relay strategy, the first copper-catalyzed asymmetric cyanation of alkyl-substituted alkenes has been developed. The reaction, featuring mild reaction conditions and excellent functional group compatibilities, provides an easy access to a wide array of structurally diverse enantioenriched alkyl nitriles in good yields. Notably, an unstable carbon-centered radical generated by trifluoromethyl radical addition across terminal alkenes can be enantioselectively trapped by chiral L*Cu(CN)2 with the assistance of a carbonyl group.