METHOD OF PRODUCING SUBSTITUTED DIANHYDRIDES OF 1(4)-SUBSTITUTED-7,8-DIPHENYLBICYCLO[2,2,2] OCT-7 ENE-2,3,5,6-TETRACARBOXYLIC ACIDS FOR SYNTHESIS OF STABLE REFRACTORY POLYMERS Russian patent published in 2015 - IPC C07D493/02 C07D307/89 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing substituted dianhydrides of 7,8-diphenylbicyclo[2.2.2]oct-7 ene-2,3,5,6-tetracarboxylic acids, which can be used in the production of stable refractory polymers. The method includes condensing 2.5-molar excess maleic anhydride with 2(5)-substituted 4-hydroxy-3,4-diphenylcyclopent-2-en-1-one at 200-225°C, followed by extraction of the end product. The diene precursor used is substituted 4-hydroxy-3,4-diphenylcyclopent-2-en-1-one; the dienophile is maleic anhydride; condensation is carried out without a solvent and at 200-225°C; and extraction of the end product is carried out by treating the reaction mixture with boiling acetic acid. The invention therefore enables to obtain dianhydrides of 7,8-diphenylbicyclo[2.2.2]oct-7 ene-2,3,5,6-tetracarboxylic acids which contain different substitutes in the "head bridge" of the bicyclic system with high output.

EFFECT: high output.

7 ex