磁性Y-MOF@SiO_2@Fe_3O_4催化剂的制备及其在Aza-Micheal加成反应中的性能（英文）

Preparation and Properties for Aza-Micheal Addition Reaction of Magnetic Y-MOF@SiO_2@Fe_3O_4 Catalysts

在磁性SiO_2@Fe_3O_4纳米微球表面原位合成包覆不同含量的Y-MOF,从而制备出新型磁性Y-MOF@SiO_2@Fe_3O_4催化剂。采用XRD、TEM、FT-IR、VSM和N_2吸附-脱附测试等手段对催化剂的结构进行表征,并且评价了催化剂对苯胺和丙烯酸甲酯的Aza-Micheal加成反应性能。结果表明Y-MOF能均匀包覆在磁性SiO_2@Fe_3O_4纳米微球表面,形成具有核壳结构的磁性YMOF@SiO_2@Fe_3O_4催化剂,催化剂具有良好的超顺磁性。Y-MOF含量为43.3%(w/w)的Y-MOF@SiO_2@Fe_3O_4催化剂,在苯胺和丙烯酸甲酯的Aza-Micheal加成反应表现出最好的催化性能,丙烯酸甲酯的转化率为88.3%时,N-(β-甲氧碳酰乙基)苯胺的选择性可达99.8%。反应后的催化剂可以通过外磁场容易回收,并且重复使用5次其转化率和选择性没有明显下降。

The magnetic Y-MOF@SiO2@Fe3O4 catalysts with different Y-MOF contents were synthesized by encapsulating magnetic SiO2@Fe3O4 nanospheres into Y-MOF through an in-situ method.The structure of the catalyst was characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM),infrared spectroscopy(FT-IR),vibration sample magnetometer(VSM)and the N2 adsorption-desorption test.The performance of the catalyst for Aza-Micheal addition reaction with aniline and methyl acrylate was evaluated.The results showed that Y-MOF was uniformly coated on the surface of the SiO2@Fe3O4 nanospheres to form a core-shell magnetic Y-MOF@SiO2@Fe3O4 catalyst.The catalysts exhibited good superparamagnetism.When Y-MOF content was 43.3%(w/w),the Y-MOF@SiO2@Fe3O4 catalyst had better catalytic performance for the Aza-Micheal addition reaction.The conversion of methyl acrylate was 88.3%and the selectivity of N-(β-methoxycarbonylethyl)aniline was 99.8%.After reaction,the catalyst was recovered by magnetic recovery.It was reused five times,and still has high conversion and selectivity.