The Enantioselective Dakin-West Reaction

摘要

Here we report the development of the first enantioselective Dakin-West reaction, yielding alpha-acetamido methylketones with up to 58% ee with good yields. Two of the obtained products were recrystallized once to achieve up to 84% ee. The employed methylimidazole-containing oligopeptides catalyze both the acetylation of the azlactone intermediate and the terminal enantioselective decarboxylative protonation. We propose a dispersion-controlled reaction path that determines the asymmetric reprotonation of the intermediate enolate after the decarboxylation.