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51.
The synthesis, characterization, and evaluation of a Schiff base Cu (II) complex functionalized boehmite nanoparticles (Cu-complex-boehmite) as a new catalyst for oxidation of sulfides and thiols in the presence of hydrogen peroxide with complete selectivity and high conversion under solvent-free and mild reaction conditions were reported. Characterization of the catalyst was performed with various physicochemical methods. This effective catalyst was evaluated in terms of activity and reusability. It indicated high catalytic activity, good recoverability and reusability, and supplied the corresponding products in high yields and short reaction times. In addition, it shows notable advantages such as simplicity of operation, heterogeneous nature, easy work up, and it could be used at least eight times with no significant loss of its activity. 相似文献
52.
Mohammad Mehdi Khodaei Davood Kordestani 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2403-2405
Abstract Direct conversion of acylals to the corresponding bisulfites can be easily performed in the presence of bismuth (III) nitrate pentahydrate in ethanol at room temperature in good yields. 相似文献
53.
54.
In this study, the biologically active configurations composed of Thiazolidinedione–Uracil (TU) and Rhodanine–Uracil (RU) have been fully investigated from the energetic and structural points of view, employing B3LYP and M062X functionals in combination with the different basis sets. Dispersion corrections to the interaction energy using M062X–GD3 and double hybrid density functionals (B2PLYP–GD2, B2PLYP–GD3 and mPW2PLYP–GD2) are also taking into account. The basis set superposition error-corrected interaction energy for hydrogen bonded configurations ranges from ??5.27 to ??13.53 and ??5.25 to ??12.93 kcal/mol for TU and RU complexes respectively as calculated at M062X/6–311++G(df,pd) level. The charge transfer process within all of the TU and RU configurations were analyzed using Natural Bond Orbital (NBO) calculations. The nature of the interactions is analyzed with NBO and Atoms in Molecules (AIM) analysis at M062X/6–311++G(df,pd) and energy decomposition analysis at BP86–D3/TZ2P(ZORA)//M062X/6–311++G(df,pd) level of theory. The results confirm that the nature of the interactions is nearly electrostatic, with a contribution of about 51–56% of the total interaction energy. The orbital interactions (ΔEorb) for the considered TU and RU complexes have a contribution of about 24–38% of the total interaction energy. Based on the AIM and NBO results, the interactions were defined as electrostatic H-bonds with partially covalent character. In addition, correlation between interaction energies and vibrational frequency changes was investigated. 相似文献
55.
56.
Mohammad Kazem Rofouei Mehdi Khodadadian Ali Reza Jalalvand Armin Beiza 《International journal of environmental analytical chemistry》2013,93(6):665-675
A new PVC-membrane electrode for Co2+ ions based on N,N′-di(thiazol-2-yl)formimidamide (TF) as membrane carrier has been developed. The electrode resulted in Nernstian response (29.5?±?0.4?mV decade?1) for Co2+ ion over a wide concentration range (2.5?×?10?7 ?1.0?×?10?1?M) with a detection limit of 6.1?×?10?8?M. The sensor has a response time of about 10?s, and can be used for at least 2 months without observing any deviation from the Nernstain response. The electrode revealed good selectivity towards cobalt(II) ion over a wide variety of alkali, alkaline earth, transition, and heavy metal ions and could be used in the pH range 2.0–7.0. The electrode was used for determination of Co2+ in real samples. 相似文献
57.
Ebrahim Soleimani Mohammad Mehdi Khodaei Afsaneh Taheri Kal Koshvandi 《Comptes Rendus Chimie》2012,15(4):273-277
An environmentally friendly and simple method for the synthesis of alkyl nitriles or β-cyanocarbonyls via a one-pot three-component reaction of Meldrum's acid, aldehydes and sodium cyanide in water, without using any catalyst or activation at room temperature is reported. 相似文献
58.
Mehdi Shafiee Ahmad R. Khosropour Iraj Mohammadpoor-Baltork Majid Moghadam Shahram Tangestaninejad Valiollah Mirkhani 《Tetrahedron letters》2012,53(24):3086-3090
A novel, diastereoselective, one-pot synthesis of new bis-Betti bases via condensation of dihydroxynaphthalene, two equivalents of aryl aldehydes, and two equivalents of 3-amino-5-methylisoxazole is reported. Conversion into the adducts was almost quantitative without the use of solvent or catalyst. The reaction conditions are very simple and enable easy isolation of the product. 相似文献
59.
Mehdi Rimaz Hossein Mousavi Laya Nikpey Behzad Khalili 《Research on Chemical Intermediates》2017,43(7):3925-3937