Synthesis of novel enantiopure biphenyl P,N-ligands and application in palladium-catalyzed asymmetric addition of arylboronic acids to N-benzylisatin

Abstract

Enantiopure tetra-ortho-substituted biphenyl phosphinoimine ligands (R(a),S)-3 and (S(a),S)-3 were synthesized via multistep reactions. The first asymmetric addition reactions of arylboronic acids to N-benzylisatin catalyzed by Pd(OAc)(2) and (R(a),S)-3 were studied to provide 3-aryl-3-hydroxyoxindoles in moderate yields and enantioselectivities.