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351.
Hakimeh Ebrahimiasl Davood Azarifar Jamshid Rakhtshah Hassan Keypour Masoumeh Mahmoudabadi 《应用有机金属化学》2020,34(9):e5769
In this research study we designed and synthesized CoII(macrocyclic Schiff base ligand containing 1,4-diazepane) immobilized on Fe3O4 nanoparticles as a novel, recyclable, and heterogeneous catalyst. The nanomaterial was fully characterized using various techniques such as Fourier-transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, energy-dispersiveX-ray spectroscopy, thermogravimetric analysis, vibrating sample magnetometry, differential reflectance spectroscopy, Brunauere–Emmette–Teller method, inductively coupled plasma, and elemental analysis (CHNS). Then, the catalytic performance was successfully investigated in the multicomponent synthesis of 2-amino-4-aryl-6-(phenylsulfanyl)pyridine-3,5-dicarbonitrile and 2-amino-5,10-dioxo-4-aryl-5,10-dihydro-4H-benzo[g]chromene-3-carbonitrile derivatives. Furthermore, the catalyst was isolated using a simple filtration, and recovery of the nanocatalyst was demonstrated five times without any loss of activity. 相似文献
352.
Moradi Ahmad Toghraie Davood Isfahani Amir Homayoon Meghdadi Hosseinian Ali 《Journal of Thermal Analysis and Calorimetry》2019,137(5):1797-1807
Journal of Thermal Analysis and Calorimetry - This paper presents the results of an experimental investigation on the heat transfer characteristics of multi-walled carbon nanotube aqueous... 相似文献
353.
In the present study, for the first time N‐(3‐silyl propyl) diethylene triamine N,N',N''‐tri‐sulfonic acid (SPDETATSA) was grafted on magnetic Fe3‐xTixO4 nanoparticles. The structure of the resulted nanoparticles was characterized based on Fourier‐transform infrared (FT‐IR), energy‐dispersive X‐ray spectroscopy (EDX), scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermal gravimetric analysis (TGA), and vibrating sample magnetometer (VSM) analyses. The results confirmed the successful immobilization of sulfamic acid groups onto the magnetic support. These nanoparticles exhibited high catalytic activity as novel magnetically recyclable acid nanocatalyst in the synthesis of a diverse range of hexahydroquinolines through one‐pot tandem reactions in excellent yields. Also, this nanocatalyst performed satisfactory catalytic maintenance of activity for the synthesis of the reaction products after 4 rounds of recycling with no considerable loss of activity. 相似文献
354.
Novel Pd nanoparticles were prepared in five successive stages: 1) preparation of the Fe3O4 magnetic nanoparticles (Fe3O4 MNPs), 2) coating of Fe3O4 MNPs with SiO2 (Fe3O4@SiO2), 3) functionalization of Fe3O4@SiO2 with 3‐chloropropyltrimethoxy‐ silane (CPTMS) ligand (Fe3O4@SiO2@CPTMS), 4) further functionalization with 3,5‐diamino‐1,2,4‐triazole (DAT) ligand (Fe3O4@SiO2@CPTMS @DAT), and 5) the complexation of Fe3O4@SiO2@CPTMS@DAT with PdCl2 (Fe3O4@SiO2@CPTMS@ DAT@Pd). Then, the obtained Pd nano‐catalyst characterized by different methods such as the elemental analysis (CHN), FT‐IR, XRD, EDX, SEM, TEM, TG‐DTA and VSM. Finally, the Pd catalyst was applied for the synthesis of various 2‐imino‐3‐phenyl‐2,3‐dihydrobenzo[d]oxazol‐5‐ols. 相似文献