苯并噻唑盐催化多聚甲醛合成1,3-二羟基丙酮

在氮气保护下,以多聚甲醛为原料,正丁醇作溶剂,三乙胺作助催化剂,在溴化-3-乙基苯并噻唑盐催化作用下合成了1,3-二羟基丙酮。考察了反应温度、反应时间、三乙胺用量对产物1,3-二羟基丙酮(DHA)收率的影响,得出的优选工艺参数为:60 mmol多聚甲醛,3 mmol催化剂和25 mL三乙胺,同时加入10 mL正丁醇,反应温度130℃,反应时间40 min。DHA收率为37%,选择性在95%～98%。产物经过先酯化再水解分离的提纯工艺,质量分数从90%提高到99.8%,分离提纯后得率为72%。产物熔点为73℃;通过IR、1HNMR及紫外可见光谱分析确证了化合物的结构。

Study on the synthesis of DHA from paraformalclehyde by the catalysis of benzothiazolium

1,3-Dihydroxyacetone was synthesized from paraformalclehyde catalyzed by 3-ethylbenzothiazolium bromide under the protection of nitrogen with butyl alcohol as dissolvent and triethylamine as cocatalyst.The effects of reaction temperature,reaction time and the amount of triethylamine on the yield of 1,3-dihydroxyacetone were investigated.The optimized synthesis parameters are as follows:the consumption of paraformalclehyde and catalyst is 60 mmol and 3 mmol respectively,the amount of triethylamine and butyl alcohol is 25 mL and 10 mL respectively,the reaction temperature is 130 ℃,and the reaction time is 40 min.The yield of DHA is 37%,and the reaction selectivity is within the range of 95%~98%.The purity of the product was increased from 90% to 99.8% after the purification processes of successive esterification and hydrolysis separation,and the total yield of DHA was 72% after the purification processes.The melting point of the product is 73 ℃.Its structure was confirmed via analysis of IR,1HNMR and ultraviolet visible spectrum.