甜菜碱离子液体[Betaine][Lac]催化合成氧杂蒽类化合物

Ionic liquid([Betaine][Lac])-catalyzed synthesis of xanthenediones

本文以甜菜碱离子液体[Betaine][Lac]作为催化剂合成氧杂蒽类化合物,反应以芳香醛和5,5-二甲基-1,3-环己二酮作为底物,以少量乙醇作为溶剂,在室温下完成反应。不同取代基(吸电子基和供电子基)的芳香醛参与反应都可得到目的产物且产率达90%,产物通过核磁进行结构鉴定。反应过程具有反应时间短和操作简单的优点,此外离子液体作为催化剂可以循环使用5次以上,并保持其催化活性。

Ionic Liquid（ [ Betaine] [ Lac] ） was found to efficiently catalyze the condensation for the synthesis of xanthenediones from aromatic aldehydes and 5 ,5-dimethyl-l ,3-cyclohexanedione in ethanol to give the corresponding products under mild and environ-mentally benign condition. Various aryl aldehydes containing electron-withdrawing groups and electron-donating groups afforded the desired products up to 90% yield. The products were characterized by !H NMR. The present procedure had the merits of short reac-tion time and simple reaction work up. Moreover,this catalyst could be reused for at least five consecutive runs without any loss of its catalytic activity.