Cyclophanes. V. Biphenylnaphthalenophanes and the synthesis of Hexa[7]circulene

Abstract

2,13-Dithia[3,3](3,3')biphenyl(2,7)naphthalenophane (5) was prepared from 3,3'-bis(bromomethyl)- biphenyl and 2,7-bis(mercaptomethyl)naphthalene. Ring contraction of (5) followed by elimination of the sulphur function gave [2,2](3,3')biphenyl(2,7) naphthalenophane-l,ll-diene (11) which on photochemical oxidative ring closure yielded hexa[7]circulene (3) a non-alternant hydrocarbon. The thermal elimination of methylsulphenic acid under vacuum is shown to be an efficient method for the