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    Efficient synthesis of propargylamines in aqueous media catalyzed by au nanoparticles under ambient temperature

    , Article ChemistrySelect ; Volume 3, Issue 7 , 2018 , Pages 2053-2058 ; 23656549 (ISSN) Matloubi Moghaddam, F ; Pourkaveh, R ; Sharif University of Technology
    Wiley-Blackwell  2018
    Abstract
    An eco-friendly gold-based catalyst supported on proline decorated montmorillonite was synthesized. The catalyst was characterized by combination of Fourier-transform infrared spectroscopy (FT-IR), Field Emission Scanning Electron Microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), Brunauer–Emmett Teller (BET) surface area analysis, Ultraviolet–visible spectroscopy (UV-Vis), Energy-dispersive X-ray spectroscopy (EDX), thermo gravimetric analysis (TGA) and atomic absorption spectroscopy (AAS) techniques. The synthesized catalyst was found to be a highly efficient heterogeneous nanocatalyst for multi component A3 coupling reaction of aldehyde, amine and alkyne... 

    Palladium immobilized onto functionalized magnetic nanoparticles as robust catalysts for amination and room-temperature ullmann homocoupling of aryl halides: a walk around the C−F bond activation

    , Article Asian Journal of Organic Chemistry ; Volume 7, Issue 4 , 2018 , Pages 802-809 ; 21935807 (ISSN) Matloubi Moghaddam, F ; Pourkaveh, R ; Karimi, A ; Ayati, E ; Sharif University of Technology
    Wiley-VCH Verlag  2018
    Abstract
    The first example of a heterogeneous catalytically active system for Buchwald–Hartwig and Ullmann homocoupling of unactivated aryl halides (fluorobenzene) is presented. The novel magnetic heterogeneous palladium catalyst was synthesized by immobilization of palladium ions onto an aminopyridine-functionalized Fe3O4. The catalyst was fully characterized by FTIR spectroscopy, temperature-programmed reduction, thermogravimetric analysis, CHN elemental analysis, transmission electron microscopy, field-emission scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, and atomic absorption spectroscopy. By using this catalyst system, various types of primary and... 

    Cobalt-copper ferrite nanoparticles catalyzed click reaction at room-temperature: green access to 1,2,3-triazole derivatives

    , Article ChemistrySelect ; Volume 3, Issue 9 , 2018 , Pages 2586-2593 ; 23656549 (ISSN) Matloubi Moghaddam, F ; Pourkaveh, R ; Ahangarpour, M ; Sharif University of Technology
    Wiley-Blackwell  2018
    Abstract
    A typical Cobalt-Copper ferrite nanoparticles (CoCuFe2O4) was used as a catalyst for one-pot [3+2] cycloaddition of alkyl azides with alkynes at room temperature in green media. These nanoparticles were synthesized by using co-precipitation method and were fully characterized by physiochemical technique. By this catalyst system, various types of alkyl halides were coupled with alkynes efficiently to furnish 1,2,3 triazoles in excellent yields within short reaction time. The requirement on energy and time for the Click reaction extremely minimized in this method compared to previously reported reactions as an inevitable trend in development of green chemistry. Using green solvent, inexpensive... 

    Waste-free and environment-friendly uncatalyzed synthesis of dithiocarbamates under solvent-free conditions

    , Article Synlett ; Issue 18 , 2007 , Pages 2797-2800 ; 09365214 (ISSN) Azizi, N ; Ebrahimi, F ; Aakbari, E ; Aryanasab, F ; Saidi, M.R ; Sharif University of Technology
    2007
    Abstract
    A mild, convenient, and practical one-pot procedure for the direct synthesis of dithiocarbamates has been developed by condensation of amines, CS2, and a Michael acceptor, under solvent-free conditions at room temperature in good to excellent yields. © Georg Thieme Verlag Stuttgart  

    A simple and novel eco-friendly process for the one-pot synthesis of dithiocarbamates from amines, carbon disulfide, and epoxides

    , Article Synlett ; Issue 8 , 2007 , Pages 1239-1242 ; 09365214 (ISSN) Azizi, N ; Pourhasan, B ; Aryanasab, F ; Saidi, M. R ; Sharif University of Technology
    2007
    Abstract
    An environmentally benign, highly efficient, and simple protocol for the synthesis of various structurally divergent dithiocarbamate derivatives in one-pot reaction of amines, carbon disulfide, and epoxides, without using any solvent and catalyst at room temperature, is presented. This new procedure has the advantages of higher yield, lower cost, reduced environmental impact, and simple work-up procedure. © Georg Thieme Verlag Stuttgart  

    Synthesis, characterization and application of magnetic room temperature dicationic ionic liquid as an efficient catalyst for the preparation of 1,2-azidoalcohols

    , Article Journal of Molecular Liquids ; Volume 183 , 2013 , Pages 14-19 ; 01677322 (ISSN) Godajdar, B. M ; Kiasat, A. R ; Hashemi, M. M ; Sharif University of Technology
    2013
    Abstract
    An environmentally benign, aqueous synthesis of 1,2-azidoalcohols via regioselective ring opening of their epoxides using magnetic imidazolium based dicationic room temperature ionic liquid, [pbmim](FeCl4)2, as an efficient magnetic phase transfer catalyst in water has been described. The present approach offers the advantages of clean reaction, simple methodology, short reaction time, high yield, easy purification and reusable catalyst  

    Sensitive and selective room temperature H2S gas sensor based on Au sensitized vertical ZnO nanorods with flower-like structures

    , Article Journal of Alloys and Compounds ; Volume 628 , April , 2015 , Pages 222-229 ; 09258388 (ISSN) Hosseini, Z. S ; Mortezaali, A ; Iraji Zad, A ; Fardindoost, S ; Sharif University of Technology
    Elsevier Ltd  2015
    Abstract
    Pursuing a sensing structure with a large effective surface area, partial ordered arrays of ZnO nanorods with flower-like structures are introduced for gas sensing applications. Room temperature H2S response of the grown structure shows significant enhancement after modification with Au nanoparticles. High response (about 1270 at 6 ppm H2S gas) and selectivity were achieved by depositing an Au layer with nominal thickness ∼6 nm. X-ray photoelectron spectroscopy (XPS) was utilized to describe the H2S sensing mechanism  

    Efficient synthesis of novel 3-substituted coumarin-3-carboxamide

    , Article Journal of the Korean Chemical Society ; Vol. 58, Issue. 2 , 20 April , 2014 , pp. 186-192 ; ISSN: 2234-8530 (Online) Sheikhhosseini, E ; Balalaie, S ; Bigdeli, M. A ; Habibi, A ; Moghaddam, H. P ; Sharif University of Technology
    Abstract
    A series of novel pseudopeptides contained coumarin skeleton were synthesized through the Ugi-four-component reaction. The 3-substituted coumarin-3-carboxamides were formed through reaction of benzaldehyde derivatives, anilines, coumarin-3- carboxylic acid and isocyanides with high yields and high bond-forming efficiency at room temperature. These novel amidated coumarins exhibit brilliant fluorescence in range of 535-547 nm in chloroform  

    ZnO nanoparticles: An efficient nanocatalyst for the synthesis of β-acetamido ketones/esters via a multi-component reaction

    , Article Catalysis Communications ; Volume 9, Issue 2 , 2008 , Pages 299-306 ; 15667367 (ISSN) Mirjafary, Z ; Saeidian, H ; Sadeghi, A ; Matloubi Moghaddam, F ; Sharif University of Technology
    2008
    Abstract
    A convenient one-pot multi-component reaction of aromatic aldehydes, enolizable ketones or β-keto esters and acetonitrile in the presence of acetyl chloride and 10 mol% ZnO nanoparticles for the synthesis of β-acetamido ketones/esters at room temperature is described. © 2007 Elsevier B.V. All rights reserved  

    Synthesis of novel water-soluble aminodeoxychitin derivatives

    , Article Starch/Staerke ; Volume 59, Issue 11 , 2007 , Pages 557-562 ; 00389056 (ISSN) Pourjavadi, A ; Seidi, F ; Salimi, H ; Sharif University of Technology
    2007
    Abstract
    Eight new chitin derivatives have been synthesized via SN2 reaction of primary and secondary amines with tosylchitin. The products were characterized using FTIR and 1H NMR spectroscopy. A degree of substitution ∼ 1 was achieved through this process. These materials are soluble in water at room temperature, which enable their further applications in the future. © 2007 WILEY-VCH Verlag GmbH & Co. KGaA  

    Molybdenum liquid salts immobilized on ionic liquid-modified silica as efficient heterogeneous catalysts for sulfoxide reduction

    , Article Tetrahedron Letters ; Volume 54, Issue 29 , 2013 , Pages 3765-3768 ; 00404039 (ISSN) Bagherzadeh, M ; Ghazali Esfahani, S ; Sharif University of Technology
    2013
    Abstract
    Two room temperature liquid salts containing molybdenum(VI), [BMIM] 2[MoO2(NCS)4] (1) and [DMIM] 2[MoO2(NCS)4] (2), were immobilized on ionic liquid-modified silica leading to materials which showed notable catalytic activity for the reduction of sulfoxides into sulfides with triphenylphosphine (PPh3). The molybdenum liquid salts immobilized on the supported ionic liquid phase could be reused at least for three catalytic cycles without significant loss of activity  

    Edge-functionalization of graphene by polyglycerol; A way to change its flat topology

    , Article Polymer (United Kingdom) ; Volume 54, Issue 12 , 2013 , Pages 2917-2925 ; 00323861 (ISSN) Movahedi, S ; Adeli, M ; Fard, A. K ; Maleki, M ; Sadeghizadeh, M ; Bani, F ; Sharif University of Technology
    2013
    Abstract
    This work presents a procedure for functionalization of graphene sheets from edges by polyglycerol. Hyperbranched polyglycerol with a bi-dentate aromatic segment in its focal point was synthesized and used to sandwich graphene sheets from the cut-edges. Due to the hydrophobicity of the flat surface of the edge-functionalized graphenes and hydrophilicity of their edges, they changed their conformation from the extended- to the closed-state and formed nanocapsules in aqueous solutions. Spectroscopy and microscopy evaluations showed that the average size for nanocapsules is 300 nm. They were able to encapsulate hydrophobic molecules such as doxorubicin in aqueous solutions with a high loading... 

    Investigation of bending and temperature effects in optical fibers

    , Article Microwave and Optical Technology Letters ; Volume 55, Issue 1 , NOV , 2013 , Pages 82-86 ; 08952477 (ISSN) Golnabi, H ; Sharifian, M ; Sharif University of Technology
    2013
    Abstract
    Fiber bending and temperature loss mechanisms in plastic optical fibers are reported.A simple arrangement is used to monitor the fiber bending and temperature by output power variation. Powers in the fibers in bend-free situation at room temperature and under rolling deforming force at different water bath temperatures (20-60°C) are measured and compared. Reported arrangements can be used as a temperature sensor  

    Novel one-pot, three-component synthesis of new 2-alkyl-5-aryl-(1H)- pyrrole-4-ol in water

    , Article Journal of Organic Chemistry ; Volume 73, Issue 6 , 2008 , Pages 2090-2095 ; 00223263 (ISSN) Khalili, B ; Jajarmi, P ; Eftekhari Sis, B ; Hashemi, M. M ; Sharif University of Technology
    2008
    Abstract
    (Chemical Equation Presented) New 2-alkyl-5-aryl-(1H)-pyrrole-4-ol derivatives were synthesized via three-component reaction of β-dicarbonyl compounds with arylglyoxals in the presence of ammonium acetate in water at room temperature. © 2008 American Chemical Society  

    Grafting of acrylamide onto kappa-carrageenan via γ-irradiation: Optimization and swelling behavior

    , Article Radiation Physics and Chemistry ; Volume 77, Issue 2 , 2008 , Pages 131-137 ; 0969806X (ISSN) Rezanejade Bardajee, G ; Pourjavadi, A ; Sheikh, N ; Sadegh Amini Fazl, M ; Sharif University of Technology
    2008
    Abstract
    The Taguchi method, a robust experimental design for optimization, was used for the synthesis of a superabsorbent hydrogel network using γ-rays as an initiator, energy source and crosslinker at the same time. Nine different samples of superabsorbent hydrogels were prepared in various conditions from kappa-carrageenan (κC) and acrylamide by γ-irradiation at room temperature. Considering the results of nine trials and according to analysis of variance (ANOVA), a new experimental condition with the concentrations of κC and acrylamide 1.5 g and 0.028 mol (2 g in total volume of 50 mL H2O), respectively, as well as γ-ray at the optimum total dose (7 kGy) was proposed. After preparing the desired... 

    Thickness dependence on thermal stability of sputtered Ag nanolayer on Ti/Si(1 0 0)

    , Article Applied Surface Science ; Volume 254, Issue 2 , 2007 , Pages 548-551 ; 01694332 (ISSN) Akhavan, O ; Moshfegh, A.Z ; Sharif University of Technology
    Elsevier  2007
    Abstract
    Thermal stability of Ag layer on Ti coated Si substrate for different thicknesses of the Ag layer have been studied. To do this, after sputter-deposition of a 10 nm Ti buffer layer on the Si(1 0 0) substrate, an Ag layer with different thicknesses (150-5 nm) was sputtered on the buffer layer. Post annealing process of the samples was performed in an N 2 ambient at a flow rate of 200 ml/min in a temperature range from 500 to 700 °C for 30 min. The electrical property of the heat-treated multilayer with the different thicknesses of Ag layer was examined by four-point-probe sheet resistance measurement at the room temperature. Phase formation and crystallographic orientation of the silver... 

    Dimensional accuracy analysis of wax patterns created by RTV silicone rubber molding using the Taguchi approach

    , Article Rapid Prototyping Journal ; Volume 13, Issue 2 , 2007 , Pages 115-122 ; 13552546 (ISSN) Rahmati, S ; Akbari, J ; Barati, E ; Sharif University of Technology
    2007
    Abstract
    Purpose - Dimensional accuracy analysis of wax model created by room temperature vulcanization (RTV) silicone rubber molding to be used in investment casting is presented. The purpose of this paper is to discuss the effective parameters of dimensional accuracy in RTV tooling technique. Design/methodology/approach - After producing a pattern by stereolithography (SLA) and then creating the RTV silicone rubber mold by the SLA pattern, dimensional accuracy of wax models produced by RTV tool are analyzed. Design of experiments (DOE) using the Taguchi approach is used for analysis and determination of optimum condition. Findings - Experiments show that the dimensional accuracy in RTV technique is... 

    ZrOCl2·8H2O on montmorillonite K10 accelerated conjugate addition of amines to α,β-unsaturated alkenes under solvent-free conditions

    , Article Tetrahedron ; Volume 62, Issue 4 , 2006 , Pages 672-677 ; 00404020 (ISSN) Hashemi, M. M ; Eftekhari-Sis, B ; Abdollahifar, A ; Khalili, B ; Sharif University of Technology
    2006
    Abstract
    At room temperature, ZrOCl2·8H2O on montmorillonite K10 efficiently catalyzes conjugate addition of amines to a variety of conjugated alkenes such as α,β-unsaturated carbonyl compounds, carboxylic esters, nitriles and amides under solvent-free conditions. The catalyst can be recycled for subsequent reactions without any appreciable loss of efficiency. © 2005 Elsevier Ltd. All rights reserved  

    Solvent parameters effects on the second-order rate constants of the reaction of 2-chloro-3,5-dinitropyridine with aniline in aqueous solutions of alcohols

    , Article Progress in Reaction Kinetics and Mechanism ; Volume 31, Issue 2 , 2006 , Pages 117-127 ; 14686783 (ISSN) Harifi Mood, A. R ; Masumpour, M. S ; Gholami, M. R ; Sharif University of Technology
    Science Reviews Ltd  2006
    Abstract
    Aromatic nucleophilic substitution reaction kinetics of 2-chloro-3,5-dinitropyridine with aniline was studied in aqueous solutions of methanol, ethanol, and 2-propanol at room temperature. The obtained results for aqueous solutions indicate that the second-order rate constants are in order of 2-propanol>ethanol>methanol with a maximum at water mole fraction of 0.9. The influence of solvent parameters including normalized polarity (E TN), dipolarity/polarisability (π*), and hydrogen bond donor acidity (α) on the second-order rate constants were investigated and multiple regressions gave much better results with regard to single parameter regressions. Dipolarity/polarisability and hydrogen... 

    N-benzyl-DABCO-tribromide as an efficient and mild reagent for deprotection of dithioacetals

    , Article Synthetic Communications ; Volume 36, Issue 8 , 2006 , Pages 1093-1096 ; 00397911 (ISSN) Moghaddam, F. M ; Boeini, H. Z ; Zargarani, D ; Bardajee, G. R ; Sharif University of Technology
    2006
    Abstract
    N-Benzyl-DABCO-ammonium tribromide was found to be an efficient and recyclable reagent for the deprotection of dithioacetals in dichloromethane/ methanol at room temperature. The reaction can be performed cleanly, in short time, and in high yield. Copyright © Taylor & Francis Group, LLC