磷钨酸催化合成7-羟基-4-甲基香豆素  

Synthesis of 7-Hydroxy-4-Methyl Coumarin Catalyzed by 12-Tungstophosphoric Acid

作　　者：张卫红[1] 吴姗姗[1] 王军[1] 任晓乾[1] 

机构地区：[1]南京工业大学化学化工学院材料化学工程国家重点实验室

出　　处：《石油化工》2008年第6期597-601,共5页Petrochemical Technology

基　　金：国家自然科学基金项目(20476046)

摘　　要：以间苯二酚和乙酰乙酸乙酯为原料,经Pechmann缩合反应合成了7-羟基-4-甲基香豆素(HMC);比较了磷钨酸、硅钨酸、磷钼酸、磷钨酸钾、磷钨酸铝及Preyssler结构的杂多酸H14NaP5W30O110的催化效果。实验结果表明,磷钨酸的催化活性最高。同时考察了在磷钨酸催化作用下反应温度、催化剂用量、反应时间和原料配比对HMC收率的影响,确定了适宜的反应条件为:n(乙酰乙酸乙酯):n(间苯二酚)=1.0,催化剂用量占反应混合物总质量的2.0%,反应温度110℃,反应时间120min;在此反应条件下,HMC的收率为84.5%。该反应具有催化剂易得、催化剂用量少、反应条件温和、反应速率快、后处理简单及产物色泽好等优点。A series of Keggin-structured heteropoly compounds including 12-tungstophosphoric acid and its potassium or aluminum salts, 12-silicotungstic acid, 12-phosphomolybdic acid, and a Preyssler- structured H14NaP5W30Oll0 compound, were used as catalysts for Pechmann condensation of resorcinol with ethyl acetoacetate to produce 7-hydroxy-4-methyl coumarin （HMC） in solvent-free condition. Catalytic activity of 12-tungstophosphoric acid is the best. Yield to HMC using 12-tungstophosphoric acid as catalyst is highest. Effects of reaction temperature, reaction time, catalyst dosage, mole ratio of resorcinol to ethyl acetoacetate on HMC yield were investigated with 12-tungstophosphoric acid as catalyst. Under optimal reaction conditions ： catalyst mass fraction in reaction system 2.0%, mole ratio of ethyl acetoacetate to resorcinol 1.0, reaction time 120 rain and reaction temperature 110 ℃, yield to HMC is 84.5%. The 12-tungstophosphoric acid-catalyzed procedure is proved to be convenient and mild with small catalyst dosage. Color of product HMC is fine.

关 键 词：Pechmann缩合 间苯二酚 乙酰乙酸乙酯 7-羟基-4-甲基香豆素 磷钨酸 杂多酸 催化剂 

分 类 号：TQ032.4[化学工程]