Skeletal Transformations of the Arylation Products ofPerfluoro(1,2-diethylbenzocyclobutene) with Tetrafluorobenzenes in the Presence ofSbF5

The reaction of perfluoro(1,2-diethylbenzocyclobutene) with 1,2,4,5-tetrafluorobenzene in SbF5, followed by hydrolysis, gave products resulting from expansion of the tetrafluorophenyl ring to cycloheptatriene. The title compound reacted with 1,2,3,5-tetrafluorobenzene to form products of opening of the four-membered ring. A similar reaction with 1,2,3,4-tetrafluorobenzene involved opening of the cyclobutane ring together with the formation of perfluoro(9,10-diethyl-9.10-dihydroanthracene) derivatives.