摘要
采用二步浸渍法制备硅胶负载磷钨酸铯（Cs2，H0.5PW12O40）催化剂催化合成药物中间体2-乙酰噻吩。运用IR和XR试D测技术进行了Cs2.5H0.5PW12O40/SiO2催化剂的表征，考察了Cs2.5H0.5PW12O40负载量、催化剂用量、物料配比、反应温度、反应时间等对2-乙酰噻吩合成收率和选择性的影响。实验结果表明，Cs2.5H0.5PW12O40和Cs2.5H0.5PW12O40/SiO2催化剂保持H3PW12O40的Keggin结构不变，且Cs2.5H0.5PW12O40/SiO2催化剂中Cs2.5H0.5PW12O40主要聚集在SiO2载体表面。优化合成2-乙酰噻吩的工艺条件为：30％Cs2.5H0.5PW12O4dSiO2催化剂用量为3％（以总物料量计）；噻吩与乙酐的摩尔比为4：1；反应温度为75～80℃；反应时间为90min。在此所选择的条件下，2-乙酰噻吩的收率达946％-96．8％，选择性达998％-99．9％。
Via two steps impregnating method, the SiO2-supported cesium-substituted dodecatungstophosphate （Cs2.5H0.5PW12O40） catalysts used for the synthesis of pharmaceutical intermediate 2-acetylthiophene were prepared. The experimental results show that in catalysts Cs2.5H0.5PW12O40 and Cs2.5H0.5PW12O40/SiO2, the primary Keggin structure of dodecatungstophosphate is preserved, and in the Cs2.5H0.5PW12O40/SiO2 catalysts, the dodecatungstophosphates mainly accumulate on the surface of the support SiO2. The optimum reaction conditions for 2-acetylthiophene synthesis were found as following： the amount of 30%Cs2.5H0.5PW12O40/SiO2 catalyst used is 3.9% （wt） of the total reaction mixture, molar ratio of thiophene to acetic anhydride is 4, reaction temperature is 75-80℃ and reaction time is 90 min. Under above selected conditions, the yield and selectivity of 2-acetylthiophene are 94.6%-96.8% and 99.8%-99.9%, respectively.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2008年第1期128-133,共6页
Journal of Chemical Engineering of Chinese Universities
关键词
2-乙酰噻吩
乙酰化
杂多酸
磷钨酸铯
阿载化
2-acetylthiophene
acetylation
heteropoly acid
cesium-substituted dodecatungstophosphate
immobilization
