BigPatents India

A process for producing 2,2'-bis (trifluoromethyl)-4,4'-diaminobiphenyl which is useful as a raw material for polyimide resin, etc.. In benzidine rearragement of 3,3'-bis(trifluoromethyl) hydrazobenzene in the presence of an inorganic acid such as sulfuric acid aqueous solution or concentrated hydrochloric acid, use of a water-immiscible organic solvent such as toluene as reaction solvent can increase the yield of the product. 3,3'-bis(trifluoromethyl) hydrazobenzene can be synthesized by reduction of m-nitrobenzotrifluoride.