【摘要】 以间苯二酚和乙酰乙酸乙酯为原料,Keggin结构磷钨酸、磷钼酸、磷钼钨酸和硅钨酸杂多酸做催化剂,在无溶剂的条件下,经Pechmann反应催化合成了7-羟基-4-甲基香豆素,该催化反应具有选择性高、不污染环境及不腐蚀设备的优点。以H4SiW12O40.15H2O催化剂为代表进行了条件优化,在n(间苯二酚)∶n(乙酰乙酸乙酯)∶n(H4SiW12O40.15H2O)=1∶1.5∶0.01,反应温度130℃,反应时间20min条件下,7-羟基-4-甲基香豆素收率为85.9%。该文报告工作的新颖性已为中国科学技术信息研究所2007年6月4日出具的第20071100100234号《科技查新报告》所证实。更多还原

【Abstract】 7-Hydroxy-4-methylcoumarin was synthesized from resorcinol and ethyl acetoacetate by Pechmann reaction using Keggin heteropolyacid(phosphotungstic acid,molybdophotungstic acid,molybdotungstophotungstic acid or silicotungstic acid) as catalyst without solvent.The reaction condition is mild and the products are easily obtained with high selectivity.Thus,with n(resorcinol)∶n(ethyl acetoacetate)=1∶1.5 and 1% (molar ratios of resorcinol) H4SiW12O40·15H2O,reaction proceeded at 130 ℃ for 20 min to give 7-hydroxy-4-methylcoumarin in 85.9% yield.The novelty of this work has been confirmed in Technology Novelty Search Report No.20071100100234 by Chinese Science and Technology Information Institute on June 4,2007.更多还原