合成医药中间体4-甲基咪唑的研究

研究了以丙酮醛、甲醛、氨／草酸铵合成４ 甲基咪唑的方法，在ｎ（ 甲醛）∶ｎ（ 丙酮醛）∶ｎ（草酸铵）＝ （１－０～１－０５）∶１－０∶（１－４ ～１－６），ｎ（ 水）∶ｎ（ 丙酮醛） ＞１７－７∶１－０，ｐＨ＝３－０～４－０，反应温度５５～６０ ℃，４ 甲基咪唑收率最高可达８３－６％ ，产品纯度＞９８－５％ 。解决了其他合成方法中产品杂质的质量分数高，生产成本高的问题，并用ＩＲ，ＮＭＲ，ＤＳＣ等对产物进行了鉴定。结果表明，该法合成的高纯度４ 甲基咪唑，其１ＨＮＭＲ、ＩＲ谱与Ａｌｄｒｉｃｈ 标准谱吻合，产品熔点达５４ ℃。

Synthesis of Medical Intermediate 4-Methylimidazole

Methylimidazole(4 MI) was synthesized by reaction of methylglyoxal,formaldehyde,and ammonia/ammonium oxalate.The molar ratio of above listed substrates was 1 0∶(1 0-1 05)∶(1 4-1 6),and n(water)/n(MGX) was above 17 7∶1 0.The reaction was carried out at 50-60 ℃ and pH 3 0-4 0.The methods cited in the references were improved and the by products decreased.Threrfore,there will be lower capital expenditure,permitting a more favorable economic operation of the process.The structure of the product was identified by IR,NMR and DSC.