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Ezzat Rafiee Mohammad Joshaghani Parvaneh Ghaderi-Shekhi Abadi 《Research on Chemical Intermediates》2018,44(4):2503-2522
Transition metal compounds have emerged as suitable catalysts for organic reactions. Magnetic compounds as soft Lewis acids can be used as catalysts for organic reactions. In this report, the Fe3O4 nanostructures were obtained from Fe2+ and Fe3+-salts, under an external magnetic field (EMF) without any protective agent. The X-ray photoelectron spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy tools were used to characterize these magnetic compounds. The two-dimensional (2-D, it showed nanometric size in the two dimensions, nanorod structure) Fe3O4 compound showed high catalytic activity and stability in N- and C-alkylation reactions. A diverse range of N- and C-alkylation products were obtained in moderate to high yield under green and mild conditions in air. Also the N- and C-alkylation products can be obtained with different selectivity and yield by exposure reactions with EMF. Results of alkylation reactions showed that the presence of Fe(II) and Fe(III) species on the surface of magnetic catalysts (phase structure of magnetic compounds) are essential as very cheap active sites. Also, morphology of magnetic catalysts had influence on their catalytic performances. After the reaction, the catalyst/product(s) separation could be easily achieved with an external magnet and more than 95% of catalyst could be recovered. The catalyst was reused at least four times without any loss of its high catalytic activity for N- and C-alkylation reactions. 相似文献
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Allahvirdinesbat Maryam Fozi Mohaddeseh Safa Kazem D. Alyari Maryam Nakhostin Panahi Parvaneh Niaei Aligholi 《Research on Chemical Intermediates》2017,43(4):2653-2668
Research on Chemical Intermediates - An improved one-pot and ecofriendly approach to tri- and tetraaryl imidazoles through three- and four-component coupling reactions under neutral and... 相似文献
54.
Kazem Karami Ali Reza Allafchian Razieh Amiri Fatemeh Shirani Parvaneh Bayat Behzad Rezaei 《应用有机金属化学》2019,33(6)
The Glucose amount of human blood is very vital because in higher levels than allowed value the corporal biological system was hampered. Therefore, in this study, the Cu2O was deposited on the reduced Graphene oxide (RGO) by polydopamin (PDA) as linker. The new RGO‐PDA‐Cu2O nanocomposite was deposited on the glassy carbon electrode (GCE) surface after its characterization by UV–Visible, fourier transform infrared (FT‐IR), X‐ray diffraction (XRD), Energy‐dispersive X‐ray (EDX), transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM) techniques. The electroanalysis of the new electrode was investigated by the cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS) methods. The obtained detection limit of glucose (Glu) showed that the deposited GCE by RGO‐PDA‐Cu2O nanocomposite has a high potential for its diagnosis. In addition, this electrode was applied to the Glu detection as biosensor in real samples in order to utilize in commercial applications. 相似文献
55.
Akram Hosseinian Arezoo Gharachorloo Tarlan Mohazzab Lighvani Parvaneh Delir Kheirollahi Nezhad Esmail Vessally 《应用有机金属化学》2018,32(10)
It has been previously reported that the recently synthesized hexa‐peri‐hexabenzocoronene (HBC) nanographene cannot detect toxic chloropicrin (CP) gas. To overcome this problem, we examined the effect of Al doping and applying an electric field on the sensitivity of HBC towards CP gas by means of density functional theory calculations. We found that the Al‐doping process significantly increases the adsorption energy of CP gas from ?7.1 to ?39.9 kcal mol?1 but decreases the sensitivity of HBC. By applying an electric field, the HBC is polarized with two different electrostatic potentials on its different surfaces, which increases the adsorption energy. By increasing the electric field strength, the adsorption energy and electronic sensitivity of HBC are increased. We predicted that in the presence of an electric field of about ?0.025 au, HBC can act as an electronic senor or a work function‐type sensor with a short recovery time. At this field, the electrical conductivity of HBC is significantly increased on CP adsorption which generates an electrical signal. Increasing the electric field to higher intensities is not favourable because of increasing recovery times, and decreasing it to lower intensities reduces the sensitivity of HBC. 相似文献
56.
Parvaneh Nakhostin Panahi Gérard Delahay 《Russian Journal of Applied Chemistry》2017,90(10):1627-1633
In this work three different supports (γ-Al2O3, ZSM-5, and SAPO-34) of varying degree of acid sites and textural properties were used to evaluate the influence of support specifics in the Cu/supported nanocatalysts on NO conversion. The nanocatalysts were prepared by homogeneous deposition precipitation (HDP) method and characterized by N2 pore size distribution, TEM, H2-TPR for investigation the reducibility of the copper species and acidity measurement by NH3 adsorption. The Cu/ZSM-5 and Cu/SAPO-34 catalysts were more active for NO conversion than Cu/γ-Al2O3 catalyst. The characterization and conversion differences in the copper supported on different types of support indicated that these differences arise from the differences in surface area, pore size distribution, and acidity of the supports. The higher SCR-DeNO activity of Cu/ZSM-5 and Cu/SAPO-34 nano-catalysts can be explained by higher surface area and acidity of ZSM-5 and SAPO-34 supports. These catalysts also have larger amount of reducible Cu species compared to Cu/γ-Al2O3 which correlates with the structure of the support used. Considering these findings, the NO conversion ability of Cu/supported catalysts has been correlated with support structure and acidity. 相似文献
57.
Ebrahim Mehdipour Parvaneh Shafieyoon Maryam Salahvarzi Vahid Amani 《Journal of the Iranian Chemical Society》2017,14(7):1575-1582
The N-(2-pyridyl) 4-toluene sulfonamide as a free ligand (PTS) was prepared from the reaction of 2-amino pyridine and 4-toluenesulfonyl chloride in the presence of potassium hydroxide solution 1 M as a base and THF was used as a solvent. The complex tetrakis [N-(2-pyridyl) sulfonamide] di palladium (1) (Pd2L4) was also prepared from the reaction of PdCl2(CH3CN)2 using (PTS) in the presence of NaOH 0.5 M and its application in Heck and Suzuki reactions. This complex consists of a binuclear unit consisting of four ligands linked to two palladium atoms via the nitrogen of pyridines ring and the nitrogen of sulfonamides. These compounds were confirmed by FT-IR and 1H NMR spectroscopy. Moreover, the structure of the complex was studied by single-crystal X-ray diffraction method. The green crystal of Pd2L4 [L = N-(2-pyridyl) sulfonamide](1) was found to crystallize in the monoclinic space group C2/c with a = 18.2013(19), b = 19.7544(16), c = 17.2898(19) Å, β = 120.179(8) °; V = 5374.0(9) Å3; Z = 4; the final R 1 = 0.0894, wR 2 = 0.1754 (or 5867 observed reflections and 318 variables). The Pd–Pd distance is 2.567(2) Å. In addition, PTS and Pd2L4 presented different antibacterial behaviors. The free ligand was active against Staphylococcus aureus and Escherichia coli, but the complex was inactive against them. 相似文献
58.
Parvaneh Shafieyoon Hosein Tavakol 《Phosphorus, sulfur, and silicon and the related elements》2018,193(5):324-328
The [N-(2-pyridyl)] para-styrene sulfonamide (PSS) was prepared as a monomer, from the reaction of para-styrene sulfonyl chloride and 2-amino pyridine in the presence of potassium hydroxide solution 0.5 M as a base, and CH3Cl. Polystyrene [N-(2-pyridyl) sulfonamide] (PPSS) was synthesized from the polymerization of [N-(2-pyridyl)] para-styrene sulfonamide (PSS). The Polystyrene bis [N-(2-pyridyl) sulfonamide] palladium (II) as a polymer- supporting palladium complex was also prepared from the reaction of PdCl2 (CH3CN)2 with PPSS in the presence of KOH 0.5 M. Polystyrene bis [N-(2-pyridyl) sulfonamide] palladium (II) is produced as a novel heterogeneous catalyst for coupling reactions for C-C bond formation. This method includes higher yield and has an easier work-up procedure. The structures of the monomer, polymer and its Pd complex were confirmed by using FT-IR and 1H-NMR spectroscopy. Elemental analysis of Pd by inductively coupled plasma (ICP) technique and hot filtration test showed loading of the metal into solution from the catalyst The heterogeneous catalyst was recycled without any loss in its properties. 相似文献
59.
K Shameli M Bin Ahmad SD Jazayeri P Shabanzadeh P Sangpour H Jahangirian Y Gharayebi 《Chemistry Central journal》2012,6(1):73
ABSTRACT: BACKGROUND: This study aims to investigate the influence of different stirring times on antibacterial activity of silver nanoparticles in polyethylene glycol (PEG) suspension. The silver nanoparticles (Ag-NPs) were prepared by green synthesis method using green agents, polyethylene glycol (PEG) under moderate temperature at different stirring times. Silver nitrate (AgNO3) was taken as the metal precursor while PEG was used as the solid support and polymeric stabilizer. The antibacterial activity of different sizes of nanosilver was investigated against Gram-positive [Staphylococcus aureus] and Gram-negative bacteria [Salmonella typhimurium SL1344] by the disk diffusion method using Mueller-Hinton Agar. RESULTS: Formation of Ag-NPs was determined by UV-vis spectroscopy where surface plasmon absorption maxima can be observed at 412-437 nm from the UV-vis spectrum. The synthesized nanoparticles were also characterized by X-ray diffraction (XRD). The peaks in the XRD pattern confirmed that the Ag-NPs possessed a face-centered cubic and peaks of contaminated crystalline phases were unable to be located. Transmission electron microscopy (TEM) revealed that Ag-NPs synthesized were in spherical shape. The optimum stirring time to synthesize smallest particle size was 6 hours with mean diameter of 11.23 nm. Zeta potential results indicate that the stability of the Ag-NPs is increases at the 6 h stirring time of reaction. The Fourier transform infrared (FT-IR) spectrum suggested the complexation present between PEG and Ag-NPs. The Ag-NPs in PEG were effective against all bacteria tested. Higher antibacterial activity was observed for Ag-NPs with smaller size. These suggest that Ag-NPs can be employed as an effective bacteria inhibitor and can be applied in medical field. CONCLUSIONS: Ag-NPs were successfully synthesized in PEG suspension under moderate temperature at different stirring times. The study clearly showed that the Ag-NPs with different stirring times exhibit inhibition towards the tested gram-positive and gram-negative bacteria. 相似文献
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Jamshid Sabbaghzadeh Parvaneh Jafarkhani Siamak Dadras Mohammad Javad Torkamany 《Applied Physics A: Materials Science & Processing》2009,94(2):293-297
Synthesis of multi-wall carbon nanotubes in a 1473 K furnace using a copper vapor laser (CVL) is reported. The operating parameters
of this laser, i.e. a high fluence at the focal point and an extremely high frequency of 10 kHz, distinguished it from common
laser sources in the synthesis of CNTs. Therefore, the unexpected experimental findings, the formation of MWNTs instead of
the generally reported SWNTs, would be verified by these two notable parameters. Electron microscopy beside Raman spectroscopy
illustrates the presence of multi-wall carbon nanotubes in the resulting product. 相似文献