Synthesis of Novel Enantiopure Biphenyl P,N-Ligands and Application in Palladium-Catalyzed Asymmetric Addition of Arylboronic Acids to N-Benzylisatin

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.