摘要:
A general synthesis of (4R*,5R*)-2-acyl-4,5-diphenyl-1,3-dioxolanes and the addition of alkylmagnesium bromides to these compounds is described. The addition reactions occur with high diastereoselectivity (typical selectivity ca. 90:10). An example addition reaction carried out on an optically active acetal proves the sense of asymmetric induction for addition of organomagnesium reagents to these alpha-keto acetals. An explanation of the mechanism of asymmetric induction is given.