The versatile cyclopropene synthon 1-bromo-2-chlorocyclopropene has be
en used to synthesize new di- and tricycloproparenes. Treatment of the
se cycloproparenes with silver ion in chloroform leads to rapid oligom
erization via carbocation intermediates to give materials in which the
aromatic systems are connected by six-membered rings. The ladder poly
mer formed by treating the linearly fused dicyclopropanaphthalene with
silver ion in chloroform has been characterized by solid state nuclea
r magnetic resonance spectroscopy.