Enantioselective Synthesis of Chiral α-Aryl or α-Alkyl Substituted Ethylphosphonates via Rh-Catalyzed Asymmetric Hydrogenation with a P-Stereogenic BoPhoz-Type Ligand

An enantioselective synthesis of optically active 1-aryl or 1-alkyl substituted ethylphosphonates, based on the first Rh-catalyzed asymmetric hydrogenation of corresponding alpha,beta-unsaturated precursors with a P-stereogenic BoPhoz-type ligand under the mild condition, was developed, in which a wide range of 1-aryl or 1-alkyl substituted ethylphosphonates were achieved in up to 98% ee.