Highly Enantioselective Rhodium-Catalyzed Hydrogenation of β-Dehydroamino Acid Derivatives Using Monodentate Phosphoramidites

Abstract

New and very easily accessible monodentate phosphoramidite ligands have been developed that lead to excellent ee's and full conversions in the hydrogenation of (E)- and (Z)-beta-dehydroamino acid derivatives with both aliphatic and aromatic side chains. Particularly, two different catalytic systems were established for (E)-beta-(acylamino)acrylates (98-99% ee) and (Z)-beta-(acylamino)acrylates (92-95% ee) based on phosphoramidites 2 and 3, respectively.