Lewis acid activation of chiral 2-trifluoromethyl-1,3-oxazolidines. Application to the stereoselective synthesis of trifluoromethylated amines, α- and β-amino acids

The reaction of chiral 2-trifluoromethyl-1,3-oxazolidines with various silylated nucleophiles under Lewis acid activation provides a stereoselective route to functionalized α-trifluoromethylamines. This methodology was successfully applied to the diastereoselective synthesis of trifluoromethylated homoallylic and propargylic amines, trifluoromethylated α-amino nitrile, β-aminoketone and β-aminoester. The α-amino nitrile and the β-amino ester were converted into (+)-3,3,3-trifluoroalanine and (+)-4,4,4-trifluoro-3-aminobutanoic acid in a one-step procedure.