Highly diastereoselective addition of organometallic reagents to a trifluoroacetaldehyde hydrazone derived from (R)-N-benzylphenylglycinol

Organolithium and Grignard reagents add efficiently with very high stereoselectivity (>98% de) to a trifluoroacetaldehyde hydrazone derived from (R)-N-benzylphenylglycinol. The addition proceeds on the re face of the chelated hydroxyhydrazone providing the (R)-α-trifluoromethylated amine after hydrogenolysis.