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 ClCH₂OMe and TiCl₄ on a variety of diphenylethanes,† which incorporates chloromethylation of a hydrocarbon followed by a Friedel–Crafts intramolecular cyclization reaction, is described.

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