Process for directed chlorination of alkylbenzenes
AssigneeHooker Chemicals & Plastics Corporation
InventorJohn C. Graham
Life of this patent
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Abstract
A process for the production of nuclear chlorinated alkylbenzenes comprises reacting, in the liquid phase, an alkylbenzene with chlorine in the presence of a Lewis acid catalyst and a co-catalyst comprising a thianthrene compound or mixture of thianthrene compounds characterized by the formula: ##STR1## where each n is 0 to 1, and each x is hydrogen or an electron-withdrawing substituent with the proviso that at least one x is an electron withdrawing substituent. The monochlorinated alkylbenzene products prepared in this manner are characterized by a desirably low ratio of ortho to para isomer.
Claims34
A process for the preparation of nuclear chlorinated alkylbenzenes which comprises reacting an alkylbenzene with chlorine at a temperature of about -25.degree. to about 150.degree. Celsius and in the presence of a Lewis acid catalyst and a co-catalyst comprising a thianthrene compound or mixture of thianthrene compounds characterized by the formula:
- ##STR17## where each n is 0 to 1 and each x is hydrogen or an electron-withdrawing substituent with the proviso that at least one x is an electron-withdrawing substituent.
A process for the nuclear chlorination of toluene which comprises reacting toluene with chlorine at a temperature of about 20.degree. to about 60.degree. Celsius in the presence of about 0.01 to about 2.0 weight percent, based on toluene, of a catalyst system consisting essentially of antimony trichloride and a mixture of thianthrene compounds characterized by the formula:
- ##STR19## where m is about 1 to about 2.5 and wherein at least a portion of said mixture is 2,3,7,8-tetrachlorothianthrene, the molar ratio of antimony trichloride to thianthrene compounds being about 0.25:1 to about 1:1.
Dependencies are inferred from the claim text.