FLUORINATIONS WITH COMPLEX METAL FLUORIDES. PART 9. FLUORINATIONS OF TOLUENE AND XYLENE DERIVATIVES BY MEANS OF CAESIUM TETRAFLUOROCOBALTATE(III)

Article abstract of DOI:10.1016/S0022-1139(00)83080-8

Benzotrifluoride at 320 deg C afforded some m-fluorobenzotrifluoride and octafluorotoluene (III), together with perfluoromethylcyclohexane (I), and also traces of 2H-heptafluorotoluene and 1-trifluoromethylnonafluorocyclohex-1-ene.Toluene itself gave (difluoromethyl)benzene, fluoro- and difluoro-methylpentafluorobenzene, difluoromethylundecafluorocyclohexane and (I); also traces of di- and tri-fluoromethylnonafluorocyclohex-1-ene: no benzotrifluoride or (III) were detected. 1,3-Bis(trifluoromethyl)benzene at 420 deg C gave 4,5,6-trifluoro-1,3-bis(trifluoromethyl)benzene, decafluoro-1,3-dimethylbenzene, and perfluoro-1,3-dimethylcyclohexane.Para-xylene at 350 deg C afforded 1,4-bis(difluoromethyl)tetrafluorobenzene, 1-difluoromethyl-4-trifluoromethyltetrafluorobenzene, decafluoro-1,4-dimethylbenzene (XIX), and perfluoro-1,4-dimethylcyclohexane (XVIII).Defluorination occurred to a significant extent on passage of the saturated cyclic fluorocarbons (I) and (XVIII) over the fully spent fluorinating agent (presumably caesium trifluorocobaltate) at ca. 400 deg C; the fluorocarbon arenes, (III) and (XIX) respectively, were obtained.