Process for separating an ar, ar-dihalo-ar-alkylbenzene from an isomeric mixture of ar, ar-dihalo-ar-alkylbenzenes

摘要

In a mixture of isomers of ar,ar-dihalo-ar-alkylbenzene wherein the halogen substituents are meta oriented with respect to each other, (e.g., a mixture of 3,5-dichlorocumene and 2,4-dichlorocumene), the 2,4-dihalo-1- alkylbenzene is preferentially reacted with an alkylating agent, e.g., an alkyl halide, by contacting the mixture with the agent in the presence of a Friedel-Crafts catalyst at a temperature of less than about 90° C. The resulting alkylated isomer is readily separated from the unreacted isomer(s) by simple distillation.