A cyclisation of humulene
Abstract
Reaction of the cycloundecatriene, humulene, with hypobromous acid gives a monocyclic and a tricyclic product. The latter has been converted into the cyclononadiene, caryophyllene, and the cycloundecatriene ring system has been regenerated from the tricycle in a variety of reactions. The mechanisms of these cyclisations and decyclisations are discussed. Bromination of cyclo-octa-1,4-diene is shown to give a cyclopropane derivative.