ABSTRACT

Magnetic nano catalysts are widely used in various organic reactions due to their characteristics of magnetic separation and recycling. Magnetic Fe₃O₄@SiO₂ nano catalyst modified by 1, 8-diazabicyclo [5.4.0]-7-undecene (DBU) was prepared and applied in the Knoevenagel reaction. The results showed that the catalyst has an excellent effect on the Knoevenagel reaction, which not only improves the reaction rate and yield, but also it can be easily separated from the reaction mixture driven by external magnetic force. Furthermore, the catalyst can be recycled 10 cycles with no loose of the catalytic activity.

中文翻译：

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水性介质中Knoevenagel反应的新型Fe3O4 @ SiO2 @丙基@DBU磁性核-壳纳米催化剂的制备

摘要

磁性纳米催化剂由于其磁性分离和再循环的特性而被广泛用于各种有机反应中。制备了由1，8-二氮杂双环[5.4.0] -7-十一碳烯（DBU）改性的磁性Fe ₃ O ₄ @SiO ₂纳米催化剂，并将其应用于Knoevenagel反应中。结果表明，该催化剂对Knoevenagel反应具有优异的效果，不仅提高了反应速率和收率，而且还易于从外力作用下与反应混合物分离。此外，该催化剂可以循环使用10个循环而不会失去催化活性。