Catalyst electronic polarizability and enantiomeric excess in asymmetric hydrogenation

In the classical rhodium–diphosphine complexes-catalyzed asymmetric hydrogenation of enamide substrates, examination on the role of catalyst electronic polarizability in the origin of enantioselectivity reveals its linear free energy relationship with the product enantiomeric ratio that is much more pronounced than analogous correlation with steric effect in the same systems. From a conceptually novel scenario, this work suggests that the often-overlooked chiral catalyst local polarizability property may function as a controlling force in enantioselection thus has important implication in rational catalyst design.