PRODUCTION OF 1,3-BIS(3,4-DICARBOXYPHENYL)1,1,3,3-TETRAMETHYLDISILOXANE DIANHYDRIDE

摘要

PURPOSE:To obtain the titled compound useful as a raw material for polyimide polymer, hardener for epoxy polymer, etc., in high productivity and yield, by mixing an ether solvent with a mixture of silicon-containing tetracarboxylic acid dianhydride isomers. CONSTITUTION:The objective compound can be produced by mixing (A) a mixture of isomers included in silicon-containing tetracarboxylic acid dianhydrides of formula I with (B) an ether solvent (preferably diethyl ether, diisopropyl ether or di-n-propyl ether) and separating produced white powder from the product. The above isomer mixture is produced by coupling a Grignard reagent of a halogeno-o-xylene with a dimethylhalogenosilane of formula II (X is halogen), hydroxylating the reaction product, hydrolyzing and oxidizing the hydroxylated product and subjecting the resultant compound of formula III to dehydrative cyclization.