Selective Preparation of Polycyclic Aromatic Hydrocarbons. Part 7.1 A Preparative Route to 10,11-Dihydro-5H-dibenzo[a,d]cyclohept enes using Friedel–Crafts Intramolecular Cyclobenzylation

Abstract

A convenient, mild, one-pot synthesis of substituted dibenzo[a,d]cycloheptenes involving the action of ClCH ₂ OMe and TiCl ₄ on a variety of diphenylethanes,† which incorporates chloromethylation of a hydrocarbon followed by a Friedel–Crafts intramolecular cyclization reaction, is described.