微波辐射下2-苯基苯并咪唑的合成及表征

Synthesis and Characterization of 2-Phenylbenzimidazole under Microwave Irradiation

用微波辐射法以多聚磷酸(PPA)作催化剂、邻苯二胺和苯甲酸为原料,合成了2-苯基苯并咪唑。用正交实验法得到了合成标题产物的优化工艺参数:n(苯甲酸)∶n(邻苯二胺)=1.2∶1(苯甲酸1.47 g,邻苯二胺1.08 g)、PPA用量11.0 g、微波辐射时间7 min及微波辐射功率280 W,2-苯基苯并咪唑的产率达81.79%。产物经熔点测试、IR、1HNMR、13CNMR表征得到了确认。

2-Phenylbenzimidazole was synthesized by the reaction of benzoic acid （Ⅰ） and ophenylenediamine （Ⅱ）. The reaction was accelerated by microwave irradiation and catalyzed by polyphosphoric acid（PPA）. By the method of orthogonal experiment the synthesis factors influencing the reaction was optimized, n （Ⅰ） ： n （Ⅱ） = 1.2：1 （ Ⅰ1.47 g, Ⅱ 1.08 g）, PPA 11.0 g, the time of microwave irradiation 7 min, and the power of microwave irradiation 280 W. Under the optimal condition, the highest yield of 2-phenylbenzimidazole is 81.79%. The samples synthesized were characterized by melting point determination, IR spectrogram, ^1HNMR spectra and ^13CNMR spectra.