Bridgehead free radicals have been produced in equimolecular mixtures of benzene and p- difluorobenzene by the thermal decomposition of the t-butylperoxyesters of 1-adamantyl, 1- bicyclo [2, 2, 2] octyl and 1-biciclo [2.2. 1] heptyl carboxylic acids. The reactivity of p- difluorobenzene relative to benzene indicated that bridgehead radicals possess nucleophilic character.
[Olah, George A.; Lee, Chang Soo; Prakash, G. K. Surya; Moriarty, Robert M.; Chander Rao, M. Suresh Journal of the American Chemical Society, 1993 , vol. 115, # 23 p. 10728 - 10732]