341-58-2

2,2'-Bis(trifluoromethyl)benzidine is used for producing a high strength flexible transparent polyimide material.

This 2,2′-bis(trifluoromethyl)-4,4′-dinitrobiphenyl crystal of 42.5 g, toluene of 127.5 g and 5% Pd/C (AER-TYPE: 50% water contained product) of 1.8 g manufactured by N.E. CHEMCAT Corp. were fed in an autoclave made of stainless steel, after the system was replaced sufficiently with hydrogen, pressured with hydrogen for a reaction pressure to be 1 MPa and reaction was carried out at a reaction temperate of 60 °C for 6 hours. After reaction, catalyst was filtered away, toluene in this reaction liquid was distilled away under reduced pressure, concentrated and crystallized, 2,2′-bis(trifluoromethyl)-4,4′-diaminobiphenyl of 28.5 g (purity converted) was obtained by solid-liquid separation.