Rhodium-catalyzed enantioselective hydrogenation of tetrasubstituted α-acetoxy β-enamido esters: a new approach to chiral α-hydroxyl-β-amino acid derivatives.

Asymmetric hydrogenation of tetrasubtitued α-acetoxy β-enamido esters with rhodium catalysts based on chiral diphosphine ligands provides an efficient and concise route to the synthesis of chiral α-hydroxyl-β-amino acid derivatives in excellent enantioselectivities. The products are valuable chiral building blocks in many biologically active compounds and have important applications in organic synthesis.