Takehiko Yamato, Masayasu Komine and Koji Matsuo
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.