PURPOSE: To obtain the subject compound useful as a polyimide raw material, etc., for semiconductor device, thin film magnetic heads, etc., by chlorinating a bis(alkoxycarbonyl-benzoic acid) with a chlorinating agent and then removing unreacted chlorinating agent and by-products by azeotropic distillation.
CONSTITUTION: Dried methanol is added to 3,3',4,4'-bisphenyltetra-carboxylic acid dianhydride and the mixture is heated under reflux to afford a bis(alkoxycarbonyl-benzoic acid), which is then packed in a four-necked flask having a gas-introducing pipe, a Liebig condenser, a thermometer and an agitator. Further, a chlorinating agent such as thionyl chloride and purified benzene are added thereto and the mixture is heated under reflux to carry out chlorination reaction and unreacted chlorinating agent and the by-products are removed at 30-50°C by azeotropic distillation to provide the objective bis(alkoxycarbonyl- benzoyl chloride) consisting of either one of compounds of formula I (R is 1-8C alkyl) to formula III or a mixture of at least two kinds of compounds thereof and useful as a polyimide raw material, etc.
MIWA TAKAO
TAKAHASHI AKIO
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