Attempted Synthesis of a Highly Strained Bicyclic Alkyne: Reaction of 8-Chloro-6,9-Dihydro-5,9-Methano-5h-Benzocycloheptene With Potassium T-Butoxide and an Anomalous Substitution Reaction at a Vinyl System

Abstract

Treatment of alkene (9) with N- bromosuccinimide gave a mixture of monobromides [(10) and (11)] which were hydrolysed to the corresponding exo alcohol (13). Oxidation of (13) and subsequent hydrogenation of unsaturated ketone (14) afforded the ketone (15). Ketone (15) was treated with PCl5, followed by potassium t- butoxide to give chloro alkene (8b). Reaction of (8b) with potassium t- butoxide resulted in the formation of unexpected allyl ether (18) whose formation mechanism has already been discussed.