A New Route for the Preparation of Fluorene Derivatives using Friedel–Crafts Intramolecular Cyclobenzylation

Abstract

A convenient preparation of fluorene derivatives based on a novel Friedel–Crafts intramolecular cyclobenzylation, involving the action of Cl₂CHOMe and TiCl₄ on a variety of biphenyls (constructed such that electrophilic substitution occurs ortho to the biphenyl linkage), is described.

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