Asymmetric epoxidation of trans-chalcones organocatalysed by β-amino alcohols

Cyclic and acyclic beta-amino alcohols were examined as organocatalysts in the epoxidation of trans-chalcones with tertbutyl hydroperoxide as the oxidant. Primary, secondary, and tertiary P-amino alcohols are able to promote the reaction with variable activity and level of asymmetric induction. Subtle modifications to the structures of simple primary P-amino alcohol strongly influenced their efficiency in the epoxidation. They are promising catalysts that afford trans-chalcone epoxides in up to 52 % ee at room temperature.