PURPOSE: After 3-nitrophthalic anhydride is subjected to chlorination, benzoylation and decomposition with dilute hydrochloric acid, the reaction mixture is only stirred in benzene under reflux to facilitate the filtration of the slurry, resulting in elimination of impurities, and finally the dehydrative ring closing reaction is effected to give the titled compound of high purity.
CONSTITUTION: In the production of 1-chloroanthraquinone through chlorination, benzoylation and dehydrative ring closure of 3-nitrophthalic anhydride, the condensation reaction of 3-chlorophthalic anhydride resulting from reaction of 3-nitrophthalic anhydride and chlorine with benzene is conducted in the presence of anhydrous aluminum chloride and the complex of the catalyst with the product is decomposed with dilute hydrochloric acid. The resultant slurry containing benzene is stirred at a temperature of benzene refluxing to improve the filtration property of the slurry and filtration is conducted. The high-quality 2-benzoyl-3-chlorobenzoic acid is dehydratively ring-closed to the objective compound.
USE: Intermediate of threne dyes. Starting material of dye intermediate.
YATABA TOORU
OOTA JIYOUSUKE
YAMAGUCHI TOYOHIKO
SUGAI CHEMICAL IND CO LTD
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