PREPARATION OF CHIRAL AMINOPHOSPHINE LIGANDS AND THEIR USE IN ASYMMETRIC HOMOGENEOUS HYDROGENATION OF ITACONIC ACID

Abstract

Optically active aminophosphines were prepared via ortho-directed metalation of appropriate arylamines followed by introduction of a diphenylphosphino group. These aminophosphines were used as ligands in the rhodium complex-catalyzed asymmetric hydrogenation of itaconic acid. Although moderate optical yields (up to 43% ee) were obtained, the stereochemical outcome with each ligand depended markedly on the chelate effect of the aminophosphines which played a significant role in both catalytic activity and enantioselectivity.