Stereoinversion in Pd-Catalyzed Allylic Substitution Induced by Modification of Olefinic Moiety in Chiral Phosphine-Acrylamide Ligands

Abstract

We synthesized a series of phosphine-acrylamide chiral compounds 4 from chiral aminophosphine (S)-5 with various acyl chlorides and demonstrated that they can be used as chiral ligands in the Pd-catalyzed asymmetric allylic substitution reactions of allylic acetate with malonates or indoles. Although the ligands shared the same axial chirality, we found that the substitution pattern of the acrylamide led to an inversion in the stereoselectivity of the product and then investigated the underlying mechanism based on DFT calculations.