The cesium salts supported on γ-Al2O3 were highly active catalysts for the Michael addition of diethyl malonate (1) to methyl acrylate (2) in toluene as solvent. The use of a limited amount of 2 gave diethyl [2-(methoxycarbonyl)ethyl]malonate (3), however the formation of diethyl bis[2-(methoxycarbonyl)ethyl]malonate (4) was enhanced by the increase in amounts of 2. Catalytic activities were easily recovered by the calcination of used catalysts. IR and XRD observations indicate that the active catalytic species are Cs2CO3 on Al2O3. The use of malononitrile enhanced the formation of the diadduct as principal products by addition to methyl acrylate. Other methyl acrylates, such as methyl methacrylate and methyl crotonate, gave low yield of the products.
负载在 γ-
Al2O3 上的
铯盐是在
甲苯溶剂中
丙二酸二乙酯 (1) 与
丙烯酸甲酯 (2) 发生迈克尔加成反应的高活性催化剂。使用有限量的 2 得到[2-(甲氧基羰基)乙基]
丙二酸二乙酯 (3),然而,双[2-(甲氧基羰基)乙基]
丙二酸二乙酯 (4) 的形成随着 2 用量的增加而增强。通过煅烧用过的催化剂很容易恢复催化活性。 IR 和 XRD 观察表明活性催化物质是
Al2O3 上的 Cs2CO3。通过与
丙烯酸甲酯加成,
丙二腈的使用增强了作为主要产物的二加合物的形成。其他
丙烯酸甲酯,例如
甲基丙烯酸甲酯和
巴豆酸甲酯,产物收率较低。