一釜合成5-氯水杨酰胺的研究

Study on 'one pot' synthesis of 5-chlorosalicylamide

在一个反应器内，5-氯水杨酸与氯化亚砜反应生成5－氯水杨酰氯，与甲醇反应生成5-氯水杨酸甲酯，再与氨气反应生成5-氯水杨酰胺。中间体不经分离提纯，总收率可达79％。结果表明，最佳氨解反应条件：氨：5－氯水杨酸甲酯=12：1（摩尔比），溶剂为甲醇，最佳反应温度为35～40℃，反应时间为15h。通过IR、MS、NMR光谱分析和元素分析，对产物的结构进行了表征。HPLC测定其纯度为99．54％。

In the presence of methanol, 5-chlorosalicyloyl chloride is synthesized from 5-chlorosalicylic acid with thionyl chloride, then 5-chlorosalicyl methyl ester is synthesized by the reaction of 5-chlorosalicyloyl chloride with methanol, finally,5-chlorosalicylamide is synthesized by the reaction of 5-chlorosalicyl methyl ester with ammonia. All the reactions were carried out in one pot. The intermediates do not need separation and purification, the total yield reaches 79%. The result showed the best ammonolysis condition：the ratio of ammonia to 5-chlorosalicyl methyl ester is 12 ： 1 ,the solvent is methanol,the temperature is 35～40℃, the ammonolysis time is 15 h. The structure of the 5-chlorosalicylamide was confirmed by the spectrograms of IR, MS, NMR and elemental analysis. The purity of 5-chlorosalicylamide reaches 99.54% （HPLC）.