FORMATION OF o-H-PERFLUOROALKYLBENZENES FROM POLYFLUOROBENZOCYCLOBUTENES IN THE HF-SbF5 SYSTEM

Article abstract of DOI:10.1007/BF00961054

HF adds to perfluorinated benzocyclobutene, 1-methyl-, and 1-ethylbenzocyclobutenes in the presence of SbF5 to give o-H-perfluoroethyl, o-H-perfluoroisopropyl-, and o-H-perfluoro-sec-butylbenzenes, respectively.The ease of this reaction decreases in the same order.Perfluoro-1,1- and perfluoro-1,2-diethylbenzocyclobutenes, perfluoroindane, and perfluorotetralin are virtually unaltered under analogues conditions.The difference in the behavior of benzocyclobutenes may be related to the stability of the carbocations, which are internediates or models of the transition stat e.This is in accord with the results of MNDO calculations with complete geometrical optimization for the relative energies of the starting compounds and intermediate ions.