以咪唑为原料,两步硝化得4,5-二硝基咪唑,再在DMF中与硫酸二甲酯反应得目标化合物1-甲基-4,5-二硝基咪唑,采用红外光谱、元素分析、质谱和核磁共振氢谱对其进行了表征.优化了合成工艺,讨论了4,5-二硝基咪唑的硝化机理.实验测得目标产物的总得率为62%,熔点为77 ℃,最佳反应条件为: 温度45～50 ℃,时间4 h ,4,5-二硝基咪唑和硫酸二甲酯的摩尔比1:6.在25 ℃,pH值由4,5-二硝基咪唑(0.63 mol·L~(-1)的丙酮溶液)的3.74升到1-甲基-4,5-二硝基咪唑(0.63 mol·L~(-1)的丙酮溶液)的6.77,酸性显著降低.%Taking imidazole as primary substance, 1-methyl-4, 5-dinitroimidazole was synthesized in DMF by reaction of methyl suifate( (CH_3)_2SO_4) with 4,5-dinitroimidazole obtained from nitration. Its structure was characterized by IR,elemental analysis,MS and H NMR. The nitration mechanism of 4,5-dinitroimidazole was analyzed. Results show that the yield of 1-methyl-4,5-dinitroimidazole is 62% ,and its melting point is 77 ℃. The optimum parameters are obtained; reaction temperature is 45-50 ℃ ,and reaction time is 4 h,the molar ratio of 4,5-dinitroimidazole to ( CH_3 )_2SO_4 is 1 : 6. The pH value of 4,5-dinitroimidazole (0. 63 mol · L~(-1) acetone solution) is raised from 3.74 to 6.77 of 1-methyl-4,5-dinitroimidazole (0.63 mol · L~(-1) acetone solution).
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