2,5-DI(METHOXYANILINO)TEREPHTHALIC ACID POLYMORPHS AND QUINACRIDONES REALIZED THEREFROM

摘要

2,5-di(p-methoxyanilino)terephthalic acid crystal types I and II are made by controlling the pH during the recovery of the oxidized product of the condensation of dimethylsuccinyl succinate with p-methoxyaniline. The resulting 2,5-di(p-methoxyanilino)-terephthalic acid can be converted into 2,9-dimethoxyquinacridone or a solid solution thereof having controlled characteristics.