Highly Enantioselective Synthesis of α-Hydroxy Phosphonic Acid Derivatives by Rh-Catalyzed Asymmetric Hydrogenation with Phosphine–Phosphoramidite Ligands
The Rh(I) complex of a monodentate phosphoramidite bearing a primary amine moiety (DpenPhos) has been disclosed to be highly efficient for the asymmetric hydrogenation of a variety of α- or β-acyloxyα,β-unsaturatedphosphonates, providing the corresponding biologically important chiral α- or β-hydroxy phosphonic acid derivatives with excellent enantioselectivities (90–>99% ee).