Diastereoselective conjugate addition of 1-(α,β-unsaturated acyl)hydantoin with nucleophiles

A diastereomeric conjugate addition of dialkylaluminum chloride to 1-(α,β-unsaturated acyl)hydantoin provided the corresponding alkyl adduct with inducted chirality in the β-position. Treatment of 1-(α,β-unsaturated acyl)hydantoin with Gilman reagent in the presence of Lewis acid also gave the same product. In this reaction, diethylaluminum chloride was the most effective Lewis acid and the absolute configuration of the major adduct at the β-position of acyl group depended on the kinds of existing metals.