Shakil Md R, Meguerdichian Andrew G, Tasnim Habiba, Shirazi-Amin Alireza, Seraji Mohammad S, Suib Steven L
Department of Chemistry , University of Connecticut , U-3060, 55 North Eagleville Road , Storrs , Connecticut 06269-3060 , United States.
Institute of Materials Science , University of Connecticut , U-3136, 97 North Eagleville Road , Storrs , Connecticut 06269-3136 , United States.
Inorg Chem. 2019 May 6;58(9):5703-5714. doi: 10.1021/acs.inorgchem.9b00053. Epub 2019 Apr 9.
Heterogeneous catalysts are preferred in fine chemical industries due to their easy recovery and reusability. Here, we report an easily scalable method of ZnO catalysts for coumarin synthesis. Nanocrystalline ZnO particles with diverse morphologies and crystallite sizes were prepared using different solvents. The change in morphology results in changes in band gaps, defects, basicity, and textural properties (surface areas, pore volumes, and pore sizes). The catalytic performances of the synthesized ZnO materials were tested using coumarin synthesis via the Knoevenagel condensation. The catalyst synthesized using methanol shows the highest activity and selectivity (conversion of 74%, selectivity of 94%) with a turnover number of 14.69. The increased activity of the ZnO synthesized in methanol is attributed to the combined effects of moderate basicity and relatively high textural properties of the sample.
由于易于回收和可重复使用，多相催化剂在精细化工行业中更受青睐。在此，我们报告了一种易于扩展规模的用于香豆素合成的氧化锌催化剂制备方法。使用不同溶剂制备了具有不同形态和微晶尺寸的纳米晶氧化锌颗粒。形态的变化导致带隙、缺陷、碱度和织构性质（表面积、孔体积和孔径）的变化。通过克诺文纳格尔缩合反应，使用合成的氧化锌材料进行香豆素合成来测试其催化性能。使用甲醇合成的催化剂表现出最高的活性和选择性（转化率为74%，选择性为94%），周转数为14.69。在甲醇中合成的氧化锌活性增加归因于样品适度碱度和相对较高织构性质的综合作用。
