CATALYTIC ASYMMETRIC EPOXIDATION OF NAPHTHOQUINONE DERIVATIVES UNDER PHASE-TRANSFER-CATALYZED CONDITIONS

2-Alkyl-1,4-naphthoquinones were smoothly transformed to the correspon ding epoxides in moderate to goad yields with good enantioselectivitie s (up to 76% ee) under mild reaction conditions by use of a catalytic amount of chiral quaternary ammonium salts derived from quinidine as a phase-transfer catalyst.