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111.
Design and synthesis of a magnetic hierarchical porous organic polymer: A new platform in heterogeneous phase‐transfer catalysis
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Recyclable phase transfer catalysts containing magnetic nanoparticles (MNPs) have been known as a major trend towards sustainable catalysts. In this study, a novel class of magnetic porous polymer on the basis of calix[4]resorcinarene was synthesized starting from silica‐coated Fe3O4 core‐shell nanoparticles. This compound was found as an efficient phase transfer catalyst to the conversion of benzyl halides into benzyl azides and cyanides in good yields. The catalyst could be used at least for five consecutive cycles without appreciable loss in the catalytic activity. 相似文献
112.
Lab-on-a-chip (LOC) technologies can take advantage of sheath flows for particle/cell focusing before sensing or sorting. The integration of focusing with other microscale manipulation techniques (e.g., sorting) creates a trade-off between the throughput of the device and its performance. Therefore, exploring the effective parameters for cells/particles focusing enables us to improve the desired output of LOC devices. A common configuration for sheath-assisted focusing is Y junctions, which are parametrically studied in this paper. First, a computational model was developed and validated by comparing it with our experimental results. Using COMSOL Multiphysics modeling, the effects of multiple parameters were studied. These parameters include the sheath flow ratio (sheath flow over total flow), width ratio (width of the sheath inlet over the total width), junction angles, and particle size on the focusing width and the distribution of the particles within the focusing region. Then, the numerical data were used to develop two generalized linear models to predict the focusing width of the particles and the standard deviation of the position of the particles. The results showed that the focusing width is greatly impacted by the sheath flow rate ratio. Further, the standard deviation of the position of the particles, which represents the concentration of the particles, is mostly dependent on the flow rate ratio, width ratio, and particle size. Our results provide a better understanding of how the device geometrical and operational factors affect the position of the particles in the development of high-performance on-chip sensing and sorting of both cells and particles. 相似文献
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Mohammadi Masoud Ghorbani-Choghamarani Arash 《Research on Chemical Intermediates》2022,48(6):2641-2663
Research on Chemical Intermediates - In this study, a novel amino acid-based Ni complex was immobilized on SiO2-modified Hercynite magnetic nanoparticles as the support to prepare the... 相似文献
115.
Taiebeh Tamoradi Mohammad Ghadermazi Arash Ghorbani-Choghamarani 《Journal of Saudi Chemical Society》2019,23(7):846-855
In the present study, oxidative coupling of thiols was carried out using immobilized Cu, Ni and Pd complexes on SBA-15 mesostructured as novel and green heterogeneous catalysts under mild reaction conditions. These supported complexes were characterized by FT-IR, XRD, TEM, TGA, EDX, ICP and BET techniques. These nanohybrid robust catalysts have outstanding advantages such as facile synthesis, use of green medium, high surface area, easy separation and workup, excellent reused for several consecutive cycles without noticeable change in its catalytic activity, and short reaction time. 相似文献
116.
Arash Ghorbani-Choghamarani Zahra Taherinia Mohsen Nikoorazm 《Research on Chemical Intermediates》2018,44(11):6591-6604
A magnetic ionic liquid supported on γ-Fe2O3 nanocatalyst was synthesized successfully and characterized by Fourier transform infrared spectroscopy, vibrating sample magnetometry, thermogravimetric analysis, differential scanning calorimetry, X-ray diffraction and scanning electron microscopy. The resulting nano-Fe3O4-supported, ionic liquid was an efficient catalyst for preparation of a series of tetracyclic quinazoline compounds by three components reaction of a mixture of isatoic anhydride and amine with ninhydrin in PEG and the desired products were obtained in good to excellent yields. High efficiency, waste-free, mild reaction conditions, effortless magnetic recovery and reusability up to four continuous cycles are the noteworthy features of the currently employed heterogeneous catalytic system. 相似文献
117.
Arash Ghorbani-Choghamarani Zahra Heidarnezhad Bahman Tahmasbi Gouhar Azadi 《Journal of the Iranian Chemical Society》2018,15(10):2281-2293
In this work, Boehmite nanoparticles (BNPs) were synthesized in water using commercially available materials and further N,N,N′,N′-tetraethyldiethylentriamin (TEDETA) was supported on the surface of BNPs, and used as organo-basic catalyst in four-component Hantzsch reaction that provides access to pharmaceutically polyhydroquinoline derivatives and Knoevenagel reaction to afford α,β-unsaturated compounds. All products were obtained in excellent yields (89–98%) and good reaction times under green condition such as water and ethanol solvents. This catalyst was characterized using FT-IR, SEM, EDS, and TGA techniques. This catalyst was reused for several times without the significant loss of their catalytic efficiency. In addition, stability of catalyst after recycling was confirmed by TGA, SEM, EDS and FT-IR techniques. 相似文献
118.
Arash Ghorbani-Choghamarani Ali Naghipour Heshmatollah Babaee Hayedeh Heidarnezhad Behrouz Notash 《Journal of the Iranian Chemical Society》2018,15(9):2123-2134
In this study, palladium (II) chloride reacted with the phosphonium salt [PhCH2COOCH2P(Ph)3]Br to give [PhCH2COOCH2P(Ph)3]2[Pd2Br6] (1). The characterization of synthesized compound was performed by elemental analysis, FT-IR, 1H, 31P, 13C NMR and also X-ray crystallography. It was found that this compound works as an efficient catalyst for the amination of aryl halides to afford primary amines, the results of which were satisfactory. Furthermore, it was found that the catalyst showed a high activity for Suzuki carbon–carbon cross-coupling of aryl halides and phenylboronic acid. Interestingly, the catalyst can be recovered from the reaction mixture and recycled four consecutive runs without any significant loss in activity. 相似文献
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[reaction: see text]. A mild and general protocol for the copper-free Sonogashira coupling of aryl bromides with acetylenes has been developed. The use of (AllylPdCl)2 and P(t-Bu)3 provides the active Pd(0) catalyst that allows subsequent coupling of various alkynes at room temperature with good to excellent yields. 相似文献