A wide variety of epoxides and aziridines M ere converted to the correspond
ing beta -halohydrins and beta -haloamines using cerium(III) chloride and t
he cerium(III) chloride/Nal system in acetonitrile. The reactions were high
ly regioselective and efficient with excellent yields under mild and neutra
l reaction conditions. (C) 2001 Elsevier Science Ltd. All rights reserved.