为了改进1-甲基-2,4,5-三碘基咪唑（MTII）的合成路线，提高总得率，探索了其新的合成工艺。新工艺以N-甲基咪唑为原料，在 CH3COOH/I2/HIO3体系中碘化，然后在丙酮/水中精制，得到 MTII。对目标产物进行了红外光谱、质谱、核磁等分析，并推断了反应机理，同时讨论了加料顺序、物料比、反应时间及反应温度对目标物得率的影响。通过单因素实验得到正确的加料顺序和最佳的反应条件分别为：将碘溶解于冰乙酸中，碘酸溶解于稀硫酸中，使两种溶液均匀混合，随后再加入N-甲基咪唑和四氯化碳且n(碘酸)/n(N-甲基咪唑)=1.8，n(碘)/n(N-甲基咪唑)=1.7，反应温度为75℃，反应时间为2.5h。，最高得率为70%。相对于传统合成工艺而言，新工艺在合成路线、反应时间、总得率等方面具有显著优点，有更好的实际应用价值。%In order to improve the synthetic route of 1-methyl-2,4,5-triiodoimidazole(MTII) and increase the rate of it,a new synthetic process was explored. MTII was synthesized by using N-methylimidazole as starting material via iodination of CH3COOH/I2/HIO3 aqueous solution and then refined in acetone/water. The target product was characterized by IR,1H NMR,MS and elemental analysis. The mechanism of reaction was discussed and effects of charging sequence,material ratio, reaction temperature and reaction time on the yield of the title compound were investigated. Through single factor experiments,the optimum reaction condition was determined that the molar ratio of HIO3 andN-methylimidazole was 1.8∶1,the molar ratio of I2 andN-methylimidazole was 1.7∶1,the reaction temperature was 75℃,and the reaction time was 2.5h. The two solutions were mixed uniformly when I2 and HIO3 dissolved in acetic acid and dilute sulfuric acid respectively,then N-methylimidazole and CCl4 were put in the reaction liquid as the optimum feeding sequence obtained. The yield of the MTII was up to 70% under the above condition. The new synthetic process has significant advantages and a better practical application value than traditional synthetic process,such as synthetic route,reaction time,the yield and so on.
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