一水硫酸氢钠无溶剂催化合成4-甲基香豆素  

NaHSO_4·H_2O Catalyzed Synthesis of Coumarin Derivatives under Solvent-Free Conditions

作　　者：杨金会[1] 计从斌[1] 赵艳敏[1] 

机构地区：[1]宁夏大学能源化工重点实验室,银川750021

出　　处：《有机化学》2008年第10期1740-1743,共4页Chinese Journal of Organic Chemistry

基　　金：国家自然科学基金(No.20562010);教育部科学技术研究重点项目基金(No.203143)资助项目.

摘　　要：NaHSO4·H2O(摩尔分数为0.1)催化下,取代酚与乙酰乙酸乙酯(物质的量比1∶1.2)在无溶剂条件下,通过Pechmann缩合反应,合成了9个4-甲基香豆素衍生物,反应时间3～5h,产率23%～91%,反应条件温和、操作简便有效.研究结果表明,当苯酚环上取代基为一个羟基或氨基能显著加速反应,提高产率,苯环上更多的取代基则对反应没有促进作用;当苯酚环上取代基为吸电子基团时,则不发生反应或者产率很低.Nine 4-methylcoumarin derivatives were synthesized from phenols and ethyl acetoaceate at a molar ratio of 1 ： 1.2 via Pechmann condensation using NaHSO4·H2O（10 mol%） as catalyst under sol- vent-flee conditions. The method was simple, green and efficient, and the reaction time was ranged from 3 to 5 h with the yields from 23% to 91%. The effects of substitution groups in the different positions of the aromatic ring on the reaction were investigated. The results showed that the activation group substituted on phenols, such as hydroxyl group or amino group, was favorable to the condensation reaction, but one more substitution group on the aromatic ring was less favorable to the reaction, the electron-withdrawing group substituted on phenols, such as nitro-group, led to no reaction or poor yields.

关 键 词：香豆素 Pechmann反应 NaHSO4·H2O 无溶剂反应 

分 类 号：TQ25[化学工程—有机化工]