甲氧苄啶中间体3,4,5-三甲氧基苯甲醛的合成

Synthesis of 3,4,5-Trimethoxybenzaldehyde-Intermediate of Trimethoprim

目的从绿色化学角度出发,得到合成甲氧苄啶中间体3,4,5-三甲氧基苯甲醛(3,4,5-trimethoxybenzaldehyde,TMB)的新工艺。方法使用溴离子作为溴源,应用氧化溴化等绿色合成方法对合成路线进行优化。结果在TMB的合成中实现了溴元素的原子经济性利用,与现存工艺相比,避免了溴素的使用,避免了高温、高压反应,总收率达到了77.7%。结论甲氧苄啶中间体TMB可以通过高原子经济性氧化溴化等多步反应进行合成,收率较高,溴化步骤溴原子利用率可达86.4%。

OBJECTIVE To obtain a new process to synthesize 3,4,5-trimethoxybenzaldehyde(TMB)-intermediate of trimethoprim from the angle of green chemistry.METHODS Synthetic process was optimized with the oxidative bromination and other methods by using bromide ion as a source of bromine.RESULTS In the synthesis of TMB,the economical utilization of bromine was realized.Compared with the existing process,the use of bromine and high temperature and high pressure reactions were avoided,and the total yield reaches 77.7%.CONCLUSION TMB-the intermediate of trimethoprim has been synthesized through high atom-economy oxidative bromination and other steps with decent yields.The yield is high,and the utilization rate of bromine atom in the bromination step can reach 86.4%.