Abstract:

3-Methyl-benzamidine hydrochloride is an important raw material and intermediate in the field of pesticide and pharmaceutical research. There are two routes to synthesize 3-methyl-benzamidine hydrochloride. The one is two-step synthesis method in which 3- methyl-benzonitrile and hydroxylamine hydrochloride react to generate 3-methyl-benzamil -doxime, and then its hydrogenation reduction occurs to get 3-methyl-benzamidine hydrochlor -ide. In the preparation of 3-methyl-benzamildoxime, the effects of conventional heating synthesis, microwave synthesis and ultrasonic synthesis were investigated. Another synthetic method is the reaction of sodium amide and 3-methyl-benzonitrile under reaction conditions close to absolute anhydrous. After the reaction was completed at room temperature, ammonium chloride was directly added to the reaction flask. This synthesis method was called one-pot method. The results were confirmed by the boiling point, MS and ¹H NMR spectrum. The experimental results show that the yield relationship of the three synthetic methods for preparing 3-methyl-benzamidoxime in the two-step synthesis method is microwave synthesis > ultrasonic synthesis> conventional heating synthesis. The total yield of the two-step synthesis method was 58.05%, and the yield by one-pot synthesis was 78.19%. Both two-step synthesis and one-pot synthesis can be used to synthesize 3-methyl-benzamidine hydrochloride.

Key words: microwave synthesis, microwave radiation, surfactants, 3-methyl-benzonitrile, 3-methyl-benzamidoxime, 3-methyl-benzamidine hydrochloride

摘要：

间甲基苯甲脒盐酸盐是农药和医药研究领域一个十分重要的原材料和中间体。间甲基苯甲脒盐酸盐的两步合成法是先以盐酸羟胺制备间甲基苯甲脒肟再通过加氢还原即可得到。在制备间甲基苯脒肟时，单因素考察了常规热反应、微波合成法、超声波合成法对间甲基苯脒肟产率的影响。并探索了一锅法合成间甲基苯甲脒盐酸盐的可行性。所得化合物由沸点、氢谱、质谱确认。实验结果表明：三种方式合成间甲基苯甲脒肟，其产率从大到小依次为：微波合成法>超声波合成法>常规热反应。本实验采用两步法合成间甲基苯甲脒盐酸盐的总产率为58.05%，采用一锅法合成间甲基苯甲脒盐酸盐的产率为78.19%。两步法和一锅法均可用于合成间甲基苯甲脒盐酸盐。

关键词: 微波合成, 微波辐射, 表面活性剂, 间甲基苯腈, 间甲基苯脒肟, 间甲基苯甲脒盐酸盐