Chiral Primary Amine Catalyzed Asymmetric Epoxidation of α‐Substituted Acroleins

Abstract 1,1‐Disubstituted terminal alkenes remain challenging substrates in asymmetric epoxidation reactions. In this study, chiral primary amines are shown to catalyze the asymmetric epoxidation of α‐substituted acroleins, a versatile type of 1,1‐disubstituted terminal alkene. Among various chiral primary amines explored, the chiral primary‐tertiary vicinal diamine derived from trans‐1,2‐diphenylethane‐1,2‐diamine is identified as the optimal catalyst, which, in combination with 5‐sulfosalicyclic acid (5‐SSA), exhibits good catalytic activity (up to 95 % yield) and enantioselectivity (up to 88 % ee). Aqueous 2 M sodium chloride was found to be the optimal reaction media.