The derivatives of toluene C 6 F 5 CH n F 3−n (n= 1−3) gave, apart from polyfluorinated 1,4-cyclohexadienes and cyclohexenes, the products of side-chain substitution of hydrogen by fluorine. This did not occur in the series of the anisole derivatives; the reactions of these compounds gave the products of high fluorination of the aromatic ring. The results of the reaction of VF 5 with deuteropentafluorobenzene allowed to make a conclusion that no CD bond cleavage takes place in the reaction ...