Highly Effective Chiral Ortho-Substituted BINAPO Ligands (<i>o</i>-BINAPO): Applications in Ru-Catalyzed Asymmetric Hydrogenations of β-Aryl-Substituted β-(Acylamino)acrylates and β-Keto Esters

Abstract

A novel family of chiral ortho-substituted BINAPO ligands (o-BINAPO) were synthesized from BINOL, and their Ru complexes were highly efficient catalysts for asymmetric hydrogenation of beta-aryl-substituted beta-(acylamino)acrylates and beta-aryl-substituted beta-keto esters. The Ru-bisphosphinite catalysts can tolerate an E/Z mixture of beta-aryl-substituted beta-(acylamino)acrylates. These highly enantioselective hydrogenations provide a useful way to prepare beta-aryl-substituted beta-amino acids and beta-hydroxyl acids.