Abstract: Disclosed is a method of making an &agr;-chloro-&agr;,&agr;-difluoro aromatic compound. An &agr;,&agr;,&agr;-trichloro aromatic compound having the general formula where Y is C or N, R is halogen, R′, amino, NHR′, NR′2, OR′, OCF3, or nitro, R′ is alkyl from C1 to C10, n is 1, 2, or 3, and m is 0 to 5, is reacted with about 0.7 to about 1.4 equivalents of hydrogen fluoride per chlorine to be replaced, in the presence of about 0.001 to about 1.5 wt %, based on wt % of said &agr;,&agr;,&agr;-trichloro aromatic compound, of a catalyst selected from the group consisting of oxides of Ti, Zr, V, Nb, Ta, Mn, Re, Fe, Ru, Os, Al, Ga, In, Ge, Sn, Sb, and Bi, MoOqXr, (M)pMos+tO3s+4t, (M)pVO3, (M)pVO5, WOqXr, (M)pWs+tO3s+4t, and mixtures thereof, where M is a cation, X is amine, phosphine, carboxylate, or ketone, p is the negative of the valence of the anion times the inverse of the valence of M, q is 0 to 3, r is 0 to 6, and s is 0 to 4, and t is 1 to 5.

Abstract: Disclosed is a method for making high purity .alpha.-chloroxylenes. A composition is formed of about 15 to about 80 wt % of a xylene and about 20 to about 85 wt % of a solvent. The solvent can be toluene, ring halogenated toluene, benzotrichloride, ring halogenated benzotrichloride, benzotrifluoride, ring halogenated benzotrifluoride, .alpha.,.alpha.,.alpha.,.alpha.',.alpha.',.alpha.'-hexafluorometaxylene, .alpha.,.alpha.,.alpha.,.alpha.',.alpha.',.alpha.'-hexafluoroparaxylene, or a mixture thereof. The composition is heated to about 70 to about 160.degree. C. No base is present in the composition. Chlorine gas is sparged through the composition and chlorine free radicals are generated therein. The chlorine free radicals can be generated either with UV light or by means of a chlorine free radical initiator.