Synthesis of 4,5-bis(4-bromophenyl)-2-phenyl-1H-imidazole and its reaction mechanism

The synthetic technology and reaction mechanism of 4,5-bis(4-bromophenyl)-2-phenyl-1H-imidazole was studied.Taking 4-bromobenzaldehyde,acetic,benzaldehyde and ammonium acetate as major raw material,the 4,5-bis(4-bromophenyl)-2-phenyl-1H-imidazole was synthesized by means of catalysis,oxidation and Debus cycloaddition reaction.The processing condition of final cycloaddition reaction was optimized and its reaction mechanism was studied.The optimized substance ratio was determined as follows: the ratio of 1,2-bis(4-bromophenyl)ethane-1,2-dione to benzaldehyde to ammonium acetate was 1∶1.2∶10,the amount of acetic acid was 2 mL,reaction time was 5 h.Under these conditions,the yield of product was 92.3%.