5-羟甲基噻唑合成工艺的改进

Improvement on synthesis of 5-hydroxymethylthiazole

5-Hydroxymethylthiazole is one of the most important medication and pesticide intermediates.5-Hydroxymethylthiazole was synthesized from 2-chloro-5-chloromethylthiazole through esterification with sodium acetate,reduction dechlorination on zinc/glacial acetic acid and hydrolysis with sodium hydroxide.For 0.05 mol 2-chloro-5-chloromethylthiazole,the results showed that the total yield of 5-Hydroxymethylthiazole was 68.3%(w(5-hydroxymethylthiazole)> 99%,GC peak area normalization method)under optimum conditions.The esterification was in 33% sodium acetate solution at 85 ℃ for 3 h;the reduction dechlorination on zinc/glacial acetic acid was the ratio of n(2-chloro-5-chloromethylthiazole)∶n(Zn)=1∶3 for 1 h;and the hydrolysis was in 25% sodium hydroxide solution at 70 ℃～75 ℃ for 2 h.The structure of 5-hydroxy-methylthiazole was confirmed by element analysis,IR,LC-MS,1H NMR and 13C NMR.

5-Hydroxymethyhhiazole is one of the most important medication and pesticide intermediates. 5-Hydroxymethylthiazole was synthesized from 2-chloro-5-chloromethyhhiazole through esterification with sodium acetate, reduction dechlorination on zinc/ glacial acetic acid and hydrolysis with sodium hydroxide. For 0.05 tool 2-chloro-5-chloromethyhhiazole,the results showed that the total yield of 5-Hydroxymethyhhiazole was 68.3% （w （5-hydroxymethyhhiazole） 〉 99%, GC peak area normalization method ） under optimum conditions. The estefification was in 33% sodium acetate solution at 85 ℃ for 3 h;the reduction dcchlorination on zinc/glacial acetic acid was the ratio of n（2-chloro-5-chloromethyhhiazole）：n（Zn） = 1：3 for 1 h; and the hydrolysis was in 25% sodium hydroxide solution at 70 ℃ - 75 ℃ for 2 h. The structure of 5-hydroxy- methyhhiazole was confirmed by element analysis, IR,LC-MS, ^1H NMR and 13 C NMR.