ChemInform Abstract: Heterocyclic Cycloproparenes: 5H‐Cycloprop(f)isobenzofuran and 5H‐Cyclopropa(f)benzothiophene.

Abstract

154ChemInform Abstract The cyclopropane (I) reacts with tetrabutylammonium fluoride to give the dibromocyclopropene (II). 2,3-Bis(iodomethyl)butadiene (III) is cyclized to form the furan or thiophene derivative (IV) which undergo Diels-Alder reaction with (II), forming the cycloadducts (V). Oxidation and dehydrobromination produce the aromatic compounds (VII). (VIIa) and dimethyl fumarate (VIII) yield the adduct (IX).