共查询到20条相似文献,搜索用时 15 毫秒
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A facile one-pot method to high-quality Ag-graphene composite nanosheets for efficient surface-enhanced Raman scattering 总被引:2,自引:0,他引:2
Zhang Z Xu F Yang W Guo M Wang X Zhang B Tang J 《Chemical communications (Cambridge, England)》2011,47(22):6440-6442
Ag-graphene composite nanosheets (AGCN) with adjustable size and well-controlled densities of Ag nanoparticles (Ag NPs) using Poly(N-vinyl-2-pyrrolidone) (PVP) as a reductant and stabilizer are reported. The obtained AGCN substrate is extremely suitable for surface-enhanced Raman spectroscopy (SERS). 相似文献
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Cédric Kalinski Michael Umkehrer Günther Ross Christoph Burdack Stephan D. Hoffmann 《Tetrahedron letters》2006,47(27):4683-4686
A novel one-pot two-step multi component reaction of acrylic aldehydes, bromoanilines, acids and isocyanides yielding polysubstituted indoles is described. The reaction is based on the combination of an Ugi four-component reaction followed by an intramolecular Heck-reaction. The simultaneous use of formic acid and cinnamaldehydes affords in situ generation of 1H-indoles. Convertible isocyanides can also be used with success in this Ugi/Heck strategy and enable synthesis of 1H-indole-2-carboxylic acid building blocks. 相似文献
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A simple and efficient one-pot synthesis of novel ferrocene-triamide conjugates from the reaction of ferrocenecarboxaldehyde with Meldrum’s acid and isocyanides in the presence of NH-containing compounds is described. This transformation proceeds through the creation of two CC bonds, two CN bonds, and one CO bond, leading to three peptide bonds, and presumably occurs via a domino sequence involving Knoevenagel condensation, [1+4] cycloaddition, deacetonation, and aminolysis reactions. 相似文献
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A novel and efficient protocol is developed for the synthesis of various spiro-2-amino pyrimidinones via the three-component condensation of alkyl cyanoacetates, guanidinium carbonate and N-substituted 4-piperidinones in ethanol at reflux. High yields, neutral conditions, and short reaction times are advantages of this method. 相似文献
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E. M. Abdel Bary 《高分子科学杂志,A辑:纯化学与应用化学》2019,56(7):648-657
A new method to prepare poly (vinyl alcohol) hydrogels by nebulization method.is introduced. A blend of Poly (vinyl alcohol) (PVA), sodium gum malate (SGM) and cellulose nanofibers (CNFs) originated from Catha Edulis was prepared and tested as neural tissue substitutes. Glutaraldehyde (GLA) was used as a crosslinker. Presence of SGM and CNFs in the formulation improved the nebulization process of PVA solution as well as mechanical properties of the fabricated hydrogels. The tensile strength of neat PVA films attains 46.7 MPa, while the tensile strength was 94.23 MPa for crosslinked-PVA. The tensile strength was found to increase with the increase in the CNFs content in the PVA compared with PVA/SGM. These soft tissues were characterized by using FTIR, SEM, and DSC. Scanning electron microscopy (SEM) results showed that PVA/SGM/CNFs blends has a diameter about 50 ± 8µm. The hydrogels were tested also for antimicrobial activities against pathogenic bacteria like Candida albicans (fungus), Bacillus subtilis (G + Ve), Staphylococcus aureus (G + Ve), Proteus vulgaris (G ? Ve) and Erwinia carotovora (G ? Ve). Favorable mechanical, thermal properties and biodegradation nature of the hydrogels, as well as antimicrobial property indicate that prepared hydrogels are suitable for tissue engineering applications. 相似文献
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Adri van den Hoogenband Jos H.M. Lange Wouter I. Iwema-Bakker Jack A.J. den Hartog Jord van Schaik Rolf W. Feenstra Jan Willem Terpstra 《Tetrahedron letters》2006,47(26):4361-4364
An unprecedented synthetic approach to novel 4-aryl-1-methyloxindoles is described. The method involves the intramolecular palladium-catalyzed amidation of N-methyl-2,6-dibromophenylacetamide followed by an in situ Suzuki cross-coupling reaction with a (hetero)arylboronic acid in a one-pot reaction. 相似文献
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A simple, efficient, and new method has been developed for the preparation of N,N-dimethylamides from carboxylic acids. As described below, treatment of a variety of aromatic carboxylic acids with N,N-dimethylsulfamoyl imidazole or N,N-dimethylsulfamoyl chloride in the presence of a mixture of methanesulfonic acid/phosphorus pentoxide (2:1, v/w) proceeded effectively to afford the corresponding N,N-dimethylamides in moderate to good yields. This method is easy, rapid, and good yielding for the synthesis of N,N-dimethylamides from carboxylic acids. 相似文献
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George Bratulescu 《Tetrahedron letters》2008,49(6):984-986
The synthesis of indoles is accomplished in high yields from phenylhydrazines and pyruvic acid using microwave irradiation. 相似文献
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Pranjal BezbaruahJunali Gogoi Kommuri S. RaoPranjal Gogoi Romesh C. Boruah 《Tetrahedron letters》2012,53(33):4389-4392
An efficient microwave promoted one-pot synthesis of steroidal and non-steroidal isothiazole derivatives from corresponding β-bromo-α,β-unsaturated aldehydes has been described using a sodium thiocyanate-urea system. The β-bromo-α,β-unsaturated aldehydes derivatives are efficiently synthesized from corresponding cyclic ketones using Vilsmeir formylation reaction. The synthetic protocol is also applied for the synthesis of antifungal brassilexin. 相似文献
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N. Narendra 《Tetrahedron letters》2010,51(47):6169-6173
A simple protocol for the synthesis of a new class of trithiocarbonate-linked peptidomimetics and neoglycosylated amino acids is described. N-Protected amino alkyl thiols were treated with CS2 in the presence of triethylamine (TEA) to generate trithiocarbonate salt, which upon reaction with appropriate halides afforded dipeptidomimetics in good yields. Further, the procedure was also extended for the synthesis of N,N′-orthogonally protected trithiocarbonate-linked dipeptidomimetics. 相似文献
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A convenient and efficient one-pot multi-component synthesis of novel polysubstituted 4-amino-2,3-dihydropyridines from carbonyl compounds, malononitrile and acetonitrile, using indium triflate is reported. Acetonitrile acts both as a solvent as well as a substrate. 相似文献
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A simple, straightforward, and highly efficient diastereoselective multicomponent one-pot synthesis of a series of pharmaceutically interesting functionalized piperidine derivatives has been developed based on a low-cost and environmentally benign Bi(NO3)3·5H2O catalyst via tandem reactions of 1,3-dicarbonyl compounds, aromatic aldehydes, and various amines in ethanol at room temperature. High atom-economy, good yields, eco-friendliness, and mild reaction conditions are some of the important features of this protocol. 相似文献
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K. RameshS. Narayana Murthy K. KarnakarY.V.D. Nageswar Kukuma VijayalakhshmiBethala L.A. Prabhavathi Devi R.B.N. Prasad 《Tetrahedron letters》2012,53(9):1126-1129
The new bioglycerol-based carbon catalyst acts as an efficient, readily available, and reusable catalyst for the synthesis of 2,4,5-trisubstituted imidazoles/1,2,4,5-tetrasubstituted imidazoles, when aromatic aldehyde, ammonium acetate/amine, and 1,2-diketone are reacted in acetonitrile. 相似文献
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An efficient, cost-effective and environmentally benign synthesis of novel tetracyclic bis-isoxazolopyrroloquinoline derivatives has been developed via one-pot four-component reaction of 4-amino-3-methyl-5-styrylisoxazoles, dimedone, aryl glyoxal monohydrates and 5-amino-3-methylisoxazole by employing water as a reaction medium and acetic acid (AcOH) as a green promoter. The advantages of this protocol are environmentally friendly, metal-free, less reaction time, operational simplicity, high yields, broad substrate scope and easy purification. Most significant of all, this method is green. 相似文献
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[reaction: see text]. One-pot conversion of aldehydes to trifluoromethylated bromoallylic alcohols in the presence of titanium isopropoxide and triphenylphosphine is described. 相似文献
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Ardeshir Khazaei Mohammad Ali Zolfigol Mohammad Mokhlesi Rahele Rostamian 《Journal of the Iranian Chemical Society》2013,10(6):1297-1301
In this report, synthesis, characterization and application of nano-sphere silica sulfuric acid as a novel and heterogeneous catalyst for the synthesis of β-acetamido ketone derivatives at room temperature are described. The catalyst has been identified using various techniques (XRD, SEM, TEM, EDX, TGA, FT-IR), and results show that it has a spherical shape and its particle size is between 60 and 90 nm. 相似文献
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Chengfeng Zhou Zonghua Wang Jianfei Xia Brian K. Via Feifei Zhang Yanzhi Xia Yanhui Li 《Comptes Rendus Chimie》2012,15(8):714-718
A simple, yet novel process was developed where magnetic graphene-CdS (Fe3O4-CdS/G) nanocomposites were prepared by a one-pot solvothermal route in which the reduction of graphite oxide (GO) into graphene was accompanied by the generation of CdS and Fe3O4 nanoparticles. The results of TEM and XRD studies indicate the formation of Fe3O4-CdS/G nanocomposites. Besides vibration sample magnetometry, fluorescence spectra and loading of doxorubicin (DOX) reveal that this new nanocomposite possesses good superparamagnet (44.85 emu/g), good fluorescent properties and a high loading efficiency (0.98 mg/mg). The efficient, stable, and water soluble nanocomposites are confirmed to be suitable for biomedical applications. 相似文献
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A novel and efficient method has been developed for the preparation of racemic or optically pure 1,2-diazetidine from 1-(1-hydroxy-propan-2-yl)hydrazine-1,2-dicarboxylate under very mild conditions with excellent yield. 相似文献