微波促进强酸性阳离子交换树脂催化合成2-甲基苯并咪唑

2-甲基苯并咪唑是重要的医药及染料中间体。以邻苯二胺与乙酸为原料，微波促进001 H型树脂催化合成了2-甲基苯并咪唑。通过单因素实验考察了微波功率、反应时间、原料质量配比、树脂用量、树脂重复使用对2-甲基苯并咪唑合成收率的影响。结果发现，当微波功率为455 W、树脂用量0.5 g、反应时间为30 min、邻苯二胺用量1.08 g、乙酸用量3.24 g时收率最高，可达84.8%。树脂重复使用可行性的研究表明，树脂重复使用两次后，2-甲基苯并咪唑收率从84.8%下降66.7%。结果表明相比于2-甲基苯并咪唑的传统合成方法，具有产率高、工艺操作简单、环境污染效应小等优点，不足之处在于催化剂重复使用性较差，需做进一步的研究工作。

Synthesis of 2-methyl benzimidazole catalyzed by 001-H ion exchange resin promoted with microwave

2-methyl benzimidazole，an important medicine and dye intermediate，was synthesized under microwave irradiation using diaminobenzene and acetic acid as raw materials and catalyzed by 001 H resin. The effects of microwave power，reaction time，mass ratio of raw materials，dose of resin and the reusage of 001 H resin on the yield of 2-methyl benzimidazole were investigated by single factor experiment. The results showed that the highest yield reached 84.8% under the optimum reaction conditions：microwave power 455 W，001 H resin 0.5 g，reaction time 30 min，diaminobenzene 1.08 g，and acetic acid 3.24 g. The study on the reusage of 001 H resin indicated that the yield of 2-methyl benzimidazole decreased from 84.8% to 66.7% after 001 H resin was used for three times. Compared with the traditional synthesis methods of 2-methyl benzimidazole，the method in this work has many advantages，such as higher yield，simpler process and less environmental pollution，but poor reusage of 001 H resin，which needs further research.