Rhodium-Catalyzed Hydrogenation with Phosphine-Phosphoramidite Ligands

Significance

The authors report a highly enantio­selective hydrogenation of β-aryl-, β-alkoxy-, and β-alkyl-substituted enol ester phosphonates. All substrates gave uniformly excellent yields and enantioselectivities. This work represents a significant advance over previously reported methods with regard to enantioselectivity and substrate scope (Chem. Commun. 2005, 628). The authors attribute the high levels of asymmetric induction to the use of the rigid unsymmetrical hybrid bidentate phosphorus ligand L1.