Asymmetric epoxidation catalyzed by d-glucose-derived uloses

Abstract

Three ulose catalysts ( 1– 3 ) were prepared from d-glucose via an intramolecular nitrile oxide cycloaddition (INOC) as the key step. The enantioselectivity of ulose 2 and 3 in asymmetric epoxidation was poor (up to 26% ee). Ulose 1 afforded good chemical yields (up to 83% yield) and the enantiomeric excess is up to 71% for the formation of (−)- trans-stilbene oxide.