Pd-Catalyzed Asymmetric Hydrogenation of α-Fluorinated Iminoesters in Fluorinated Alcohol:  A New and Catalytic Enantioselective Synthesis of Fluoro α-Amino Acid Derivatives

Abstract

[figure: see text] Under hydrogen pressure, a catalytic amount of palladium(II) trifluoroacetate and 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (BINAP) promoted asymmetric hydrogenation of alpha-fluorinated iminoesters to afford highly enantioenriched beta-fluorinated alpha-amino esters. The yield and ee were much improved by employing fluorinated alcohols such as 2,2,2-trifluoroethanol (up to 91% ee).