N-(4-Bromophenyl)-[1,1'-biphenyl]-4-amine

32228-99-2

1160294-93-8

The general procedure for the synthesis of N-(4-bromophenyl)-4-benzidine from N-phenyl-4-benzidine was as follows: N-phenyl-4-benzidine (35.0 g) was dissolved in DMF (700 ml) under the protection of nitrogen and cooled in an ice bath. Subsequently, N-bromosuccinimide (8.5 g) was slowly added. After the temperature of the reaction system was brought to room temperature, the remaining N-bromosuccinimide (total 17.0 g) was added in two portions. The reaction mixture was stirred at room temperature for 25.5 h. The reaction solution was slowly dripped into water (3,500 ml) to precipitate a solid, which was collected by filtration. The resulting solid was dissolved in toluene (2,500 ml) and dried by adding magnesium sulfate. The desiccant was removed by filtration and the filtrate was concentrated. To the concentrate was added hexane (500 ml) for dispersion and washing, followed by drying under reduced pressure overnight to give N-(4-bromophenyl)-4-benzidine as a slightly red solid (44.1 g, 95.4% yield).