Studies in the Tricyclooctane Series. III. Dehydrobromination of Some Bis-bromocarbene Adducts of Cyclohexadienes

Abstract

Treatment of 4,4,8,8-tetrabromo-cis-transoid-cis-tracyclo[5,1,0,0^3,5]octane (If) with potassium t-butoxide leads to mixtures of the (E)- and (Z)-isomers of 4- and 3-bronlo-β-t-butoxystyrene (5e,f) and (9e,f) respectively, whereas the 4,4,endo-8-tribromo analogue (1g) affords the parent styrenes (5c,d). On the other hand the tetra- and tri-bromo-cis-transoid-cis-tricyclo[5,1,0,0^2,4] octanes (8f-h)give complex and unresolved product mixtures. Evidence is presented which eliminates the involvement of halogenocyclooctatetraenes and p-halogenophenylacetylenes in these reactions.