Stereodivergent Pd/Cu Catalysis for the Dynamic Kinetic Asymmetric Transformation of Racemic Unsymmetrical 1,3-Disubstituted Allyl Acetates

He, R.; Huo, X.; Zhao, L.; Wang, F.; Jiang, L.; Liao, J.; Zhang, W.

Journal of the American Chemical Society 142(18): 8097-8103

ISSN/ISBN: 1520-5126

2020

PMID: 32307983

DOI: 10.1021/jacs.0c02150

Document: 035089508

A stereodivergent Pd/Cu catalyst system has been developed for the unprecedented dynamic kinetic asymmetric transformation (DyKAT) of racemic unsymmetrical 1,3-disubstituted allylic acetates with prochiral aldimine esters. A series of α,α-disubstituted α-amino acids bearing vicinal stereocenters were easily prepared with excellent enantioselectivities (up to >99% ee) and diastereoselectivities (up to >20:1 dr). Moreover, all four stereoisomers of the product can be readily obtained simply by switching the configurations of the two chiral metal catalysts. Furthermore, the present work highlights the power of synergistic Pd/Cu catalysis consisting of two common bidentate chiral ligands for stereodivergent synthesis.