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911.
Avat Arman Taherpour Ako Yari Fatemeh Ghasemhezaveh Mohammad Ali Zolfigol 《Journal of the Iranian Chemical Society》2017,14(12):2485-2493
The efficiently oxidized various types of 2-substituted imidazolines to the corresponding imidazoles using potassium permanganate supported on silica gel (KMnO4/SiO2) under mild conditions and at room temperature have been reported before. In this study, the competitive concerted, catalytic stepwise (E 1 cb′ Cat .) and E 1 cb′ mechanisms of the oxidative aromatization process of 2-imidazolines to the corresponding imidazoles using KMnO4/SiO2 have been theoretically investigated by DFT-B3LYP/6-31G** method. The achieved data from this computational study confirmed that the reaction occurs by stepwise E 1 cb′ mechanism on the basis of the anomeric effect. 相似文献
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914.
Fatemeh Mirrahimi Mohammad Ali Taher Hadi Beitollahi Rahman Hosseinzadeh 《应用有机金属化学》2012,26(4):194-198
Two amino acids – d ‐penicillamine (D‐PA) and tryptophan (TRP) – could be simultaneously determined in an aqueous solution (pH 7.0) using a novel benzoylferrocene‐modified carbon nanotube paste electrode. The results indicate that the electrode is efficient in terms of its electrocatalytic activity for the oxidation of D‐PA, leading to an overpotential reduction by more than 155 mV. Using square wave voltammetry, measurement of D‐PA and TRP in one mixture could be done independently from each other with a potential difference of about 205 mV. The proposed electrochemical sensor exhibited a linear calibration plot ranging from 1.0 × 10?6 to 8.0 × 10?4 m with a detection limit of 1.3 × 10?7 m for D‐PA. Finally, the proposed method was applied to the determination of D‐PA in a D‐PA capsule. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
915.
Experimental measurements have been performed for liquid-liquid equilibria in aqueous systems containing 1-pentanol and sodium nitrate at temperatures of 298.15 and 308.15 K and at atmospheric pressure. The results have been modeled using the extended UNIQUAC model and also a modified version of this model. Relevant model parameters have been adjusted using the experimental data. Both models are capable of correlating the experimental data with an average deviation of less than 0.8 weight percent, with the modified model producing slightly better results. The predictive nature of the models has also been verified. 相似文献
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917.
Amin Rostami Fatemeh Hassanian Arash Ghorbani-Choghamarani Shaghayegh Saadati 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):833-838
Abstract An efficient, chemoselective, and environmental friendly procedure for the oxidation of sulfides to sulfoxides is described. Various types of aromatic and aliphatic sulfides are selectively oxidized to sulfoxides in good to excellent yields using 30% H2O2 in the presence of catalytic amounts of a p-TsOH under solvent-free conditions at room temperature. 相似文献
918.
Mohammad Reza Ganjali Fatemeh Basiripour Mojtaba Shamsipur Omid Reza Hashemi Abolghasem Moghimi Hossein Aghabozorg 《International journal of environmental analytical chemistry》2013,93(12):997-1008
Pb(II), Cd(II) and Cu(II) ions were separated and preconcentrated by solid-phase extraction on octadecyl-bonded silica membrane disks modified with a new S–N-containing Schiff base (bis-2-thiophenal propandiamine) (BTPD) followed by elution and atomic absorption spectrometric detection. The method was applied as a separation and detection method for lead(II), cadmium(II) and copper(II) in environmental and biological samples. Extraction efficiency and the influence of sample matrix, flow rate, pH, and type and minimum amount of stripping acid were investigated. The maximum capacity of the membrane disks modified by 4?mg of BTPD was found to be 668 ± 10, 480 ± 8 and 454 ± 7?µg of lead, cadmium and copper, respectively. The limit of detection of the proposed method is 0.25, 0.01 and 0.02?ng/mL for lead, cadmium and copper, respectively. 相似文献
919.
The activity of dimeric [Pd{C6H4(CH2N(CH2Ph)2)} (μ‐Br)]2 complex as an efficient, air‐ and moisture‐tolerant catalyst was investigated in amination reactions of various aryl halides with secondary amines. Substituted tertiary aryl amines were produced in excellent yields and short reaction times using catalytic amounts of this dimeric complex in DMSO at 120°C. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
920.