Reaction of 30-nor-18-lupene derivatives with bromine and peracids

Abstract

The reaction of diol I and diacetate IIwith one mole of bromine gives rise, depending on conditions, to isomeric dienes III-V and IX or to derivatives substituted in position 21 (VII, VIII). On reaction of diacetate II with two moles of bromine in acetic acid 21,22-disubstituted compounds XI and XII were obtained. Diene V is the intermediate in the formation of dienes IV and IX and derivatives XI and XII. Epoxidation of the 18(19)-double bond in compounds I and II takes place from the β-side and leads for epoxides XIV and XV.