2-(1-甲基-3-吡唑基)-5-溴吡啶的合成研究

Synthesis of 2-(1-methyl-3-imidazolyl)-5-bromopyridine

2-(1-甲基-3-吡唑基)-5-溴吡啶是一种重要的医药化工中间体。以2,5-二溴吡啶为起始原料,经取代、环合得到中间体5-溴-2-(1H-3-吡唑基)吡啶。进一步与碘甲烷发生取代反应,得到目标产物和副产物2-(2-甲基-3-吡唑基)-5-溴吡啶,结构经MS和1H NMR确认。本文考察了不同的缚酸剂对5-溴-2-(1H-3-吡唑基)吡啶取代反应的影响,确定了反应最佳条件,总收率为53.2%。该合成方法原料简单易得,操作简单,反应时间短且收率较高,适合工业化生产。

2 - （ 1 - methyl - 3 - pyrazolyl ） - 5 - bromo - pyridine is an important pharmaceutical and chemical intermediate. Taking 2,5-dibromopyridine as a starting material, after substituted halogen, addition and cyclization, the intermediate 5-bromo- 2 - （ 1 H- 3 - pyrazolyl） pyridine was synthesized. After further substitution reaction with methyl iodide, the desired product and by - product 2 - （ 2 - methyl - 3 - imidazolyl ） - 5 - bromopyridine were synthesized, their structures were confirmed by MS and 1H NMR. The influence of different acid-binding agents on the substitution of 5- bromo-2-（1H-3-pyrazolyl） pyridine was investigated. The optimum reaction conditions were determined, total yield was 53.2%. The synthesis method is simple and easy to obtain, simple in operation, short in reaction time and high in yield, and is suitable for industrial production.