Diastereoselectivity

Beta-Keto Sulfoxide reduction-stereodivergent

 

diastereoisomer

Click on each of the products to view the reaction mechanism with and without ZnCl2.

In the presence of ZnCl2, the hydride transfer is intermolecular yielding the R,R enantiomer. In the absence of the ZnCl2, the hydride transfer is intramolecular delivering the hydride directly yielding the R,S enantiomer.

Summary page : Without ZnCl2 : With ZnCl2

A. Solladié-Cavallo, J. Suffert, A. Adib and G. Solladié, Tetrahedron Lett., 1990, 31, 6649–6652.