3-氨基-1,3-二甲氧基-N-氰基丙脒母液一步法合成2-氨基-4,6-二甲氧基嘧啶工艺研究

Study on synthesis of 2-amino-4,6-dimethoxypyrimidines from3-amino-1,3-dimethoxyl-N-nitrile proamidine mother solution by one-step method

以丙二腈、甲醇、单氰胺为起始原料,经亚胺化、氰胺化、环合反应得到2-氨基-4,6-二甲氧基嘧啶。环合过程在母液中直接升温闭环,以解决氰胺化反应后3-氨基-1,3-二甲氧基-N-氰基丙脒的繁琐处理工序问题。探索了反应过程中反应温度、物料配比、反应时间对产品收率的影响。研究结果表明,3-氨基-1,3-二甲氧基-N-氰基丙脒母液一步法合成2-氨基-4,6-二甲氧基嘧啶,可减少了干燥设备、缩短生产周期、减少环境污染、节约成本,收率为79.9%,接近工业生产水平,且工艺稳定,产品纯度在99%以上,适合工业化生产。

Using malonitrile,methanol and monocyanamide as starting materials,2-amino-4,6-dimethoxypyrimethamine was obtained through the reaction of iminization,cyanilization and recycling.The cyclic synthesis process directly heats up the closed loop in the mother liquid to solve the tedious processing problem of 3-amino-1,3-dimethoxyl-N-nitrile proamidine after the cyanamide reaction.The effects of reaction temperature,raw material proportion and reaction time on the yield of product were investigated.The research results show that implements the3-amino-1,3-dimethoxy-N-nitrile-2-camidine mother liquor one-step synthesis of 2-amino-4,6-dimethoxy pyrimidine,reduced drying equipment,shorten the production cycle,reduce environmental pollution,save costs,yield was79.9%,close to the level of industrial production,and process stability,product purity over 99%,suitable for industrial production.