Nucleophilic Displacement in Polyhalogenoaromatic Compounds. XIII. Polyfluoroarene Systems

Abstract

Rate coefficients are reported for the methoxydefluorination of decafluoro-biphenyl and -phen-anthrene, of octafluoro-biphenylene, -naphthalene, -acenaphthylene, and -toluene, of 4H- heptafluorotoluene and the 4-bromo and 4-phenyl analogues, and of tetradecafluoro-4,4'- dimethylbiphenyl in methanol at 298 K. These rates are compared with theoretically calculated reactivities; none give perfect correlation. The orientation of nucleophilic attack upon polyfluorinated aromatic systems may be simply understood by considering each aromatic ring to act as a single entity and neglecting the effects of the carbon substituents, so that the orientation of attack of each benzene ring is the same as that of the corresponding polyfluorobenzene.