Asymmetric Transfer Hydrogenation Coupled with Dynamic Kinetic Resolution in Water: Synthesis of anti-β-Hydroxy-α-amino Acid Derivatives

The use of asymmetric transfer hydrogenation combined with dynamic kinetic resolution for the synthesis of beta-hydroxy-alpha-(tert-butoxycarbonyl)-amino esters in water is described. This procedure provides the desired amino alcohols in good yields, diastereoselectivities, and enantioselectivities. A surfactant is employed to achieve good yields due to the hydrophobic nature of both the catalyst and substrate. The reaction setup is operationally simple, and nondegassed water can be used as the solvent.