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991.
Ghodsi Mohammadi Ziarani Parisa Gholamzadeh Alireza Badiei Vaezeh Fathi Vavsari 《Research on Chemical Intermediates》2018,44(1):277-288
Pyruvic acid contains three different reactive positions: –COOH, ketone carbonyl and methyl groups. Correspondingly, pyruvic acid was applied as starting material in the modified Niementowski reaction and Aldol condensation using SBA-Pr-SO3H as an efficient nanocatalyst. Aldol condensation of pyruvic acid and oxindole provided a new oxindol-based carboxylic acid which was subsequently used in the Ugi four-component reaction. Moreover, through the modified Niementowski reaction of pyruvic acid, new derivatives of quiazoline were produced in the presence of SBA-Pr-SO3H. The obtained products are important due to their potentially biological active skeletons. 相似文献
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Irannejad-Gheshlaghchaei Navid Zare Abdolkarim Sajadikhah Seyed Sajad Banaei Alireza 《Research on Chemical Intermediates》2018,44(10):6253-6266
Research on Chemical Intermediates - A novel dicationic ionic liquid, N,N,N′,N′-tetramethyl-N,N′-bis(sulfo)ethane-1,2-diaminium mesylate [TMBSED][OMs]2), has been produced, and... 相似文献
994.
Research on Chemical Intermediates - A novel binuclear complex of niobium(V) containing two curcuminato, and two bridging chloro ligands, was synthesized and characterized by means of nuclear... 相似文献
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Nastaran Ejlali Seyed Mohammad Hosseini 《Journal of Optimization Theory and Applications》2017,174(1):83-107
In this article, a direct pseudospectral method based on Lagrange interpolating functions with fractional power terms is used to solve the fractional optimal control problem. As most applied fractional problems have solutions in terms of the fractional power, using appropriate characteristic nodal-based functions with suitable power leads to a more accurate pseudospectral approximation of the solution. The Lagrange interpolating functions and their fractional derivatives belong to the Müntz space; such functions are employed to show that a relationship exists between the Karush–Kukn–Tucker conditions associated with nonlinear programming and the first optimal necessary conditions. Furthermore, the convergence of the method is investigated. The obtained numerical results are an indication of the behavior of the algorithm. 相似文献
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Arash Ghorbani-Choghamarani Maryam Hajjami Bahman Tahmasbi Nourolah Noori 《Journal of the Iranian Chemical Society》2016,13(12):2193-2202
In this research, project boehmite silica sulfuric acid (Boehmite-SSA) has been applied as new acidic porous catalyst for the selective oxidation of sulfides to sulfoxides and oxidative coupling of thiols to corresponding disulfides using hydrogen peroxide as oxidizing agent. The products have been obtained in short reaction times and high yields. Boehmite nanoparticles was prepared, coated by silica and then reacted with chlorosulfuric acid to obtain Boehmite-SSA. This catalyst was characterized by FT-IR, TGA/DTA, XRD, TEM, SEM, EDS and BET techniques. BET curve of boehmite nanoparticles identified as a typical type IV isotherm (definition by IUPAC), which are the characteristics of mesoporous material. Nitrogen adsorption/desorption measurement indicated that boehmite nanoparticles had BET surface area of about 122.8 m2/g. The catalyst was easily separated and reused for the several runs without significant loss of its catalytic efficiency. 相似文献