Asymmetric syntheses. Part IX. Reduction of ketone oximes and their O-substituted derivatives with the lithium aluminium hydride–3-O-benzyl-1,2-O-cyclohexylidene-α-D-glucofuranose complex to give optically active amines

Abstract

The asymmetric reduction of ketone oximes and their O-tetrahydropyranyl and O-methyl derivatives with the lithium aluminium hydride–3-O-benzyl-1,2-O-cyclohexylidene-α-D-glucofuranose complex yields optically active amines of up to 56% optical purity. The stereoselectivities obtained from reduction of the O-substituted oximes were similar to those from the reduction of the free oximes. All the resulting amines have the S-configuration and this method may be used in determining the absolute configurations of amines. Asymmetric reduction with the ethanol-modified glucofuranose complex gives optically active amines of the R-configuration.