Copper(I)-Catalyzed Asymmetric Pinacolboryl Addition of N-Boc-imines Using a Chiral Sulfoxide-Phosphine Ligand

Highly efficient and enantioselective copper(I)-catalyzed pinacolboryl addition of N-Boc-imines is reported. By using a single chiral sulfoxide-(dialkyl)phosphine (SOP) ligand, both enantiomeric isomers of alpha-amino boronic esters were obtained through an achiral counteranion switch.