Preparation and rearrangement of arylhydroxymethano[3]orthocyclo[5](1,8)naphthalenophanes

Arylhydroxymethano[3]orthocyclo[5](1,8)naphthalenophanes 11, which possess a rigid boat-chair conformation, were prepared by the reaction of 9,10-benzo-3,4,5-[1,8]naphthobicyclo[5.4.1]dodecan-3,9-dien-12-one 8c with aryllithium reagents and treated with hydrobromic acid in dioxane. The intermediary cation generated from 11 rearranged either to a benzo[cd]azulene system of type 12 or to a tricyclic system containing a cyclopropane-unit of type 13, depending on the nature of the aryl substituent on the bridging carbon atom.