STUDIES IN THE CYCLOPROPARENE SERIES - REACTIONS WITH RADICALS

The behaviour of 1H-cyclopropabenzene (1) and 1H-cyclopropa[b]naphthal ene (23) towards a variety of radicals results in opening of the three -membered ring to give ortho-substituted benzyl and 2-methylnaphthalen e derivatives, e.g. (13) and (28), respectively. Ring expansion into t he cycloheptatriene manifold by way of addition to the bridge bond and norcaradiene formation have not been observed. Analogous reactions wi th the methylidenecyclopropa[b]naphthalenes (33) and (34) lead to much decomposition, and provide little evidence for the C1 cycloproparenyl radicals (35) and (36).