Highly efficient asymmetric hydrogenation of itaconic acid derivatives catalyzed by a modified DIOP-rhodium complex

Abstract

A modified DIOP analogue bearing 4-methoxy and 3,5-dimethyl groups on each phenyl group has been synthesized. The rhodium complex of the ligand has been found to give very high optical yields in the asymmetric hydrogenation of itaconic acid and its derivatives bearing β-aryl groups, the products of which are the key-intermediates for optically active lignan derivatives.