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1.
An environmentally benign aqueous protocol for the synthesis of 3,4-dihydropyrimidin-2-(1H)-ones and thiones promoted by a green catalyst,silica gel-supported L-pyrrolidine-2-carboxylic acid-4-hydrogen sulfate,has been developed.The use of nontoxic,thermally stable and inexpensive amino acid catalyst makes the process simple with minimal amount of chemical waste.Compared with classical Biginelli reaction conditions,this new method has the advantages of high yields and simple workup procedures. 相似文献
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Using the Faber polynomials, we obtain coefficient expansions for analytic bi-close-to-convex functions and determine coefficient estimates for such functions. We also demonstrate the unpredictable behavior of the early coefficients of subclasses of bi-univalent functions. A function is said to be bi-univalent in a domain if both the function and its inverse map are univalent there. 相似文献
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This paper derived single-valued neutrosophic graphs from single-valued neutrosophic hypergraphs via strong equivalence relation. We show that any weak single-valued neutrosophic graph is a derived single-valued neutrosophic graph and any linear weak single-valued neutrosophic tree is an extendable linear single-valued neutrosophic tree. 相似文献
5.
Surface modified SPIONs‐Cr(VI) ions‐immobilized organic‐inorganic hybrid as a magnetically recyclable nanocatalyst for rapid synthesis of polyhydroquinolines under solvent‐free conditions at room temperature 下载免费PDF全文
In this work, a magnetic hybrid dichromate nanocomposite with triphenylphosphine surface modified superparamagnetic iron oxide nanoparticles (SPIONs) as a recyclable nanocatalyst was designed, prepared and characterized by Fourier transform infrared spectroscopy (FT‐IR) spectra, X‐ray diffraction (XRD) pattern analysis, vibrating sample magnetometer (VSM) curves, X‐ray fluorescence (XRF) analysis, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images and dynamic light scattering (DLS) analysis. Then, it was used in a green and efficient procedure for one‐pot multicomponent synthesis of polyhydroquinoline derivatives by the condensation of aldehydes, dimedone or 1,3‐cyclohexadione, ethyl acetoacetate and ammonium acetate. This protocol includes some new and exceptional advantages such as short reaction times, low catalyst loading, high yields, solvent‐free and room temperature conditions, easy separation and reusability of the catalyst. 相似文献
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Bagheri Maedeh Gholamzadeh Parisa Mohammadi Ziarani Ghodsi Badiei Alireza 《Research on Chemical Intermediates》2019,45(6):3301-3310
Research on Chemical Intermediates - A dual-functional silica-based catalyst was prepared by treating fumed silica with amino-containing silane then 1,4-butane sultone. The presence of functional... 相似文献
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Nasrollah Hamidi 《Journal of Macromolecular Science: Physics》2019,58(2):219-247
The thermal decomposition of post-consumer samples of a carbonated water bottle made of poly(ethylene terephthalate), PC-PET, was examined by linear temperature programing under an argon atmosphere to determine its mass loss kinetics. A simple kinetic model, called the first order pseudo single-component model, was used. The total weight-loss of each sample assumed to be in two periods, with each period corresponding to a one step decomposition of the PC-PET to volatiles. Three methods for determining the kinetic parameters by thermal gravimetric analysis were examined: differential analysis at a constant heating rate (differential), temperatures of a given conversion at a number of heating rates (isoconversional), and the maximum rate at multiple heating rates (peak temperature). The latter two multiple heating rates methods results were comparable to each other but they were not in agreement with the results from the differential method. The results of the differential method were insensitive to the heating rate and consistent with kinetics data reported in the literature for PET. 相似文献
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Smailii Parisa Pakroo Raziye Mohammadkhani Ramin Jafarian Vahab Kabiri Esfahani Farhad Hassani Leila 《Journal of the Iranian Chemical Society》2020,17(1):127-134
Journal of the Iranian Chemical Society - Herein, we investigated the interaction of cisplatin loaded on GO (GO@CDDP) with two regulatory sequences, BRCA1 and BRCA2, synthesized from ssDNA based on... 相似文献
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Ali Reza Kazemizadeh Nahid Shajari Reza Shapouri Neda Adibpour Reza Teimuri‐Mofrad Parisa Dinmohammadi 《应用有机金属化学》2016,30(3):148-153
A four‐component reaction between aromatic carboxylic acids, (N‐isocyanimino)triphenylphosphorane, ferrocenecarbaldehyde and dibenzylamine is reported. This approach is an efficient, simple and high‐yield procedure for the synthesis of 1,3,4‐oxadiazole derivatives containing a ferrocene unit. The antimicrobial activities of the products were investigated against Staphylococcus aureus and Pseudomonas aeruginosa in in vitro and in vivo assays. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献