Zinc-mediated Coupling Reaction of 2-Bromo-2,3,3,3-tetrafluoropropanoate with Various Chiral Imines. Simple and Effective Access to Optically Active (alpha)-Fluoro-(alpha)-(trifluoromethyl)-(beta)amino Esters

The reactions of benzyl 2-bromo-2,3,3,3-tetrafluoropropanoate with various types of chiral imines in the presence of zinc in THF at room temperature were revealed to afford the threo- and erythro-isomers of (alpha)-fluoro-(alpha)-(trifluoromethyl)-(beta)-amino esters with high diasteremeric excesses in fair to good chemical yields.