Catalyst compositions and their use for chlorinating aromatic compounds
View Patent ↗A method for ring-halogenating an aromatic compound comprises contacting the aromatic compound with chlorine or bromine in the presence of a catalyst composition, where the catalyst composition comprises at least one salt comprising a metal selected from the group consisting of Group 13 metal; and a counterion derived from an acid having a pKa relative to water of 0 or greater; and at least one organic sulfur compound.
1. A method for ring-chlorinating toluene or o-xylene, which comprises contacting toluene or ortho-xylene with chlorine in the presence of a catalyst composition, wherein said catalyst composition comprises:
at least one salt comprising a metal selected from the group consisting of indium and thallium; and a counterion derived from an acid, said acid having a pKa relative to water of 0 or greater; and
at least one organic sulfur compound selected from the group consisting of phenothiazine-N-carbonyl chloride, N-trifluoroacetylphenothiazine, 3-chloro-N-trifluoroacetylphenothiazine, and 3-trifluoromethyl-N-trifluoroacetylphenothiazine.
2. The method of claim 1 , wherein said at least one salt is selected from the group consisting of indium telluride, thallium sulfide, indium sulfide, thallium oxalate, and indium oxalate.
3. The method of claim 1 , wherein the catalyst composition comprises at least one reaction product of said at least one salt, and said at least one organic sulfur compound.
4. The method of claim 1 , wherein said contacting takes place in the liquid phase.
5. A method for chlorinating toluene or ortho-xylene which comprises contacting toluene or ortho-xylene with chlorine in the presence of a catalyst composition prepared by combining at least one metal salt selected from the group consisting of indium sulfide, indium telluride, thallium sulfide, and thallium oxalate; at least one organic sulfur compound; and a chlorine atom source.
6. The method of claim 5 , wherein said organic sulfur compound is selected from the group consisting of phenothiazine-N-carbonyl chloride, N-trifluoroacetylphenothiazine, 3-chloro-N-trifluoroacetylphenothiazine, and 3-trifluoromethyl-N-trifluoroacetylphenothiazine.
7. The method of claim 5 , wherein said catalyst composition comprises at least one reaction product of said at least one metal salt, and said at least one organic sulfur compound.
8. The method of claim 5 , wherein said contacting takes place in the liquid phase.
9. The method of claim 5 , wherein said chlorine atom source comprises molecular chlorine or hydrogen chloride.