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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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1,3-Dibromo-5,5-dimethylhydantoin,has been used as an efficient catalyst for the synthesis of 14-aryl-14H-dibenzo[a,j]xanthenes in the presence of kaolin.All reactions are performed in the absence of solvent in relatively short reaction times in good to high yields.  相似文献   
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In the present study, a novel magnetic carbon nanotube functionalized by chlorosulfonicacid (Fe3O4-CNT-SO3H) with nanotube morphology decorated by the spherical nanoparticles was prepared, characterized and introduced as a retrievable magnetic heterogeneous nanocatalyst for green synthesis a variety of 2-(1H-tetrazole-5-yl) acrylonitrile via multicomponent domino Knoevenagel condensation/ 1,3-dipolar cycloaddition reaction between aromatic aldehydes, malononitrile, and sodium azide under solvent free conditions. The catalyst was magnetically separated from the reaction system by an outer magnetic force and recycled up to five runs without a remarkable loss in its efficiency. The as-preparedacidic magnetic nanocomposite was characterized by different techniques inclusive Fourier transform infrared, thermogravimetric analysis, energy dispersive X-ray, field emission scanning electron microscopy, X-ray diffraction, vibrating sample magnetometry, CHNS elemental analysis, and acid-base titration. Easy workup, affordability, elimination of volatile and toxic solvents, and high yield of products are some merits of this protocol.  相似文献   
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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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Research on Chemical Intermediates - A convenient, rapid, and highly efficient procedure for synthesis of 5-substituted-1H-tetrazoles was developed via multicomponent domino Knoevenagel...  相似文献   
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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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