Copper-catalyzed asymmetric 1,2-arylboration of enamines: access to chiral borate-containing 3,3'-disubstituted isoindolinones.

An enantioselective copper-catalyzed 1,2-arylboration reaction of enamines has been developed by employing ( R )-xyl-BINAP as a chiral ligand. A number of chiral borate-containing 3,3'-disubstituted isoindolinones were obtained in moderate to good yields and good to excellent enantioselectivities from the reactions of N -( o -iodobenzoyl)enamines and bis(pinacolato)diboron (B ₂ pin ₂ ) under mild reaction conditions. Synthetic transformations of the products were conducted to demonstrate the practicality of this reaction.