|
Enantioselective addition to prochiral carbonyl compounds for the synthesis of a variety optically active compounds have been developed in the area of asymmetric organic synthesis recently. Usually the transformation of enantiotopic groups or addition to enantiotopic faces produce stereiosomers. Although there are several methods which obtaining optical compounds, the use of chiral Lewis acid generated in situ from a Lewis acid and a chiral auxiliary is necessary and very efficient process in synthesis of optically active compounds with high optical purity together with enzymatic process. Thus it is important that proposing a useful methods and suitable configuration for designing external chiral ligands. Enantioselective C-C bond formation reactions, together with reduction, oxidation and functional group transformation which lead to optically active compounds have been possible through proper combination of transition metal and well-designed chiral auxiliaries. In this paper, titanium-(1R, 2S) norephedrine-N-mesitylsulfone amide, prepared in situ from (1R, 2S) norephedrine-N-mesitylsulfone amide as chiral auxiliary and titanium derivatives as transition metal were used in order to investigate its enantioselective trimethylislylcyanation of several aldehydes (aromatic, aliphatic aldehydes).
|