自制氨基磺酸催化合成2-苯基苯并咪唑

Synthesis of 2-Phenylbenzimidazole Catalyzed by the Prepared Aminosulfamic Acid

用自制的氨基磺酸作催化剂,以邻苯二胺和苯甲醛为原料,在无水乙醇溶剂中,反应合成2-苯基苯并咪唑。通过紫外可见光谱仪、傅里叶红外光谱仪和氢核磁共振仪对产物的结构进行表征。考察了催化剂用量、原料配比、反应温度和反应时间等条件对产物收率的影响。在m(氨基磺酸)/n(邻苯二胺)为4.0 g/mol、n(邻苯二胺)/n(苯甲醛)为2.5、反应温度85℃和反应时间3.0 h的适宜条件下,产物收率最高达到71.8%。

2-phenylbenzimidazole was prepared by reaction of o-phenylenediamine and benzaldehyde in anhydrous ethanol, catalyzed by the prepared aminosulfamic acid. The product was characterized by UV- visible spectroscopy, Fourier transform infrared spectroscopy and I HNMR. The effects of catalyst dosage, reactant ratio, reaction temperature, reaction time on the yield of product were investigated. The optimal condition is that the highest yield of 2-phenylbenzimidazole is 71.8% when the reaction is carricd out with ratio of amminosulfamic acid mass to o-phenylenediamine mole of 4.0 g/mol, the ratio of o-phenylenediamine to benzaldehyde of 2.5, at 85 ℃ for 3.0 h.