Patent number: 6222078
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.
Type:
Grant
Filed:
December 10, 1998
Date of Patent:
April 24, 2001
Assignee:
Occidental Chemical Corporation
Inventors:
Sanjay Mandal, Kevin R. Benson, James Franc