FREE-RADICAL REARRANGEMENT OF BICYCLO[2.2.2]OCTENONE AND BICYCLO[4.2.0]OCTENONE SYSTEMS

Intramolecular cyclization of carbon radicals to carbonyl groups was carried out on bicyclo[2.2.2]- and bicyclo[4.2.0]octenones. An unexpected ring expansion product 19, produed by beta-scission of the intermediate alkoxyl radical 22, was observed. The beta,gamma-situated double bond of the bicyclic ketones appears to have a dampening effect on the carbon radical-ketone cyclization and the allylic cleavage of the alkoxyl radical.