重氮盐与叠氮化合物经[3+2]环加成反应是构建五唑环的关键步骤。以对氨基苯酚、2-甲基-4-氨基苯酚和 2,6-二甲基-4-氨基苯酚盐酸盐为原料,采用低温提取方法分离得到相应的盐酸重氮盐、硫酸重氮盐及四氟硼酸重氮盐固体,并通过光谱、质谱和扫描电子显微镜等确定其结构特征和形貌。热稳定性研究表明,随着苯环上羟基邻位上甲基取代个数的增加,所合成的重氮盐热稳定性越差,但四氟硼酸重氮盐的稳定性优于硫酸重氮盐和盐酸重氮盐。采用紫外光谱定性分析了不同重氮盐与叠氮化钠反应制备芳基的产率变化,结果表明,重氮盐的稳定性与其合成的芳基五唑收率呈反比关系,稳定性较差的3,5-二甲基-4-羟基苯基重氮盐酸盐合成的芳基五唑收率最好,当反应温度高于-30℃时芳基五唑的收率降低,所以合成芳基五唑温度应控制在-30℃及以下。

The cycloaddition reaction between diazonium salts and diazo compounds is a key step for synthesis of aryl pentazole.Herein,a series of diazonium salts with different acid anion including Cl^-,HSO^-₄,and BF^-₄,are prepared and separated via the low temperature extraction method by using 4-aminophenol,2-methyl-4-aminophenol,and 2,6-dimethyl-4-aminophenol hydrochloride as raw materials.Their structure and morphology are characterized by means of spectroscopy,mass spectrometry,and scanning electron microscopy.Thermal stability study indicates that the stability of synthesized diazonium salt becomes poorer with the increasing number of methyl substitution adjacent hydroxyl group on benzene ring.It is worth mentioning that tetrafluoroborate diazonium has much better stability than sulfate diazonium salt and diazonium hydrochloride.Subsequently,aryl pentazole is synthesized by reaction between sodium azide and different diazonium salts,and the yield rates are determined by means of UV-Vis spectrum.Results indicate that the yield of synthesized aryl pentazole has inverse relation with the stability of diazonium salts,where 3,5-dimethyl-4-hydroxyphenyl diazonium hydrochloride with lower stability delivers a high yield of aryl pentazole.It is also observed that the yield of aryl pentazoles declines when the reaction temperature is higher than -30℃.

刘力乐(2000-),男,硕士生,研究方向为含能材料,2770383382@qq.com;孙呈郭(1983-),男,博士,教授,研究方向为含能材料,通讯联系人,cgsun@njust.edu.cn