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    Solvatochromic parameters for binary mixtures of an ionic liquid with various protic molecular solvents

    , Article Monatshefte fur Chemie ; Volume 140, Issue 3 , 2009 , Pages 329-334 ; 00269247 (ISSN) Khodadadi Moghaddam, M ; Habibi Yangjeh, A ; Gholami, M. R ; Sharif University of Technology
    Solvatochromic parameters (E T N , normalized polarity parameter; π, dipolarity/polarizability; β, hydrogen-bond acceptor basicity; α, hydrogen-bond donor acidity) have been determined for binary mixtures of propan-2-ol, propan-1-ol, ethanol, methanol and water with recently synthesized ionic liquid (IL; 2-hydroxyethylammonium formate) at 25 °C. In all solutions except aqueous solution, E T N values of the media increase abruptly with the ILs mole fraction and then increase gradually to the value of pure IL. A synergistic behavior is observed for the α parameter in all solutions. The behavior of π and β are nearly ideal for all solutions except for solutions of methanol with the IL. The... 

    CO2 separation by supported liquid membranes synthesized with natural deep eutectic solvents

    , Article Environmental Science and Pollution Research ; Volume 28, Issue 26 , 2021 , Pages 33994-34008 ; 09441344 (ISSN) Saeed, U ; Khan, A. L ; Gilani, M. A ; Aslam, M ; Khan, A. U ; Sharif University of Technology
    Springer Science and Business Media Deutschland GmbH  2021
    Betaine-based natural deep eutectic solvents (NADESs), a new class of green solvents, were immobilized into a porous polyvinylidene fluoride (PVDF) support and evaluated for the separation of CO2 from CO2/N2 and CO2/CH4 mixtures. Two types of NADESs were synthesized by mixing betaine (hydrogen bond acceptor-HBA) with malic acid and tartaric acid (hydrogen bond donors-HBD) respectively. FTIR and Raman spectroscopy were studied to confirm the synthesis and purity of the NADESs. The thermal strength of the NADESs was investigated using thermogravimetric analysis. The gas permeation results of the fabricated NADES-based-supported liquid membranes (NADES-SLMs) showed that the permeability of CO2... 

    Systems designed with an ionic liquid and molecular solvents to investigate the kinetics of an SNAr reaction

    , Article Progress in Reaction Kinetics and Mechanism ; Volume 38, Number 2 , 2013 , pp. 157-170 Salari, H. (Hadi) ; Padervand, M. (Mohsen) ; Gholami, M. R. (Mohammad Reza) ; Hallett, Jason P ; Sharif University of Technology
    The microscopic features of binary solvent systems formed by molecular solvents (methanol, ethanol, 2-methylpropan-2-ol, water, pyridine, acetonitrile, 1-propanol, 2-propanol, dimethylformamide) and the ionic liquid ([bmim]BF4) as cosolvent were used to select mixed solvents with particular characteristics. Molecular-microscopic solvent parameters corresponding to these binary mixtures were utilised to study the kinetics of the nucleophilic substitution reaction between 2-chloro-3,5-dinitropyridine and aniline to investigate and compare the effects of the solvents on a model chemical reaction. For these mixtures, the solvation behaviour is dominated by both the dipolarity/ polarisability and... 

    Solvent effects on the reaction rate and selectivity of synchronous heterogeneous hydrogenation of cyclohexene and acetone in ionic liquid/alcohols mixtures

    , Article Journal of Molecular Catalysis A: Chemical ; Volume 306, Issues 1–2 , July , 2009 , Pages 11–16 Khodadadi-Moghaddam, M. (Mohammad) ; Habibi-Yangjeh, A. (Aziz) ; Gholamia, M. R. (Mohamad Reza) ; Sharif University of Tecnology
    Synchronous heterogeneous catalytic hydrogenation of cyclohexene and acetone, catalyzed by Pt/Al2O3, was carried out in solutions of 2-hydroxy ethylammonium formate (a room temperature ionic liquid, RTIL) with ethanol and propan-1-ol at 25 °C. Rate constants and selectivity of the reaction (relative to cyclohexene hydrogenation) increase with mole fraction of the ionic liquid (IL). The reactants tendency to the catalyst surface increases by addition of the ionic liquid and thus the reaction rate increases, especially for cyclohexene hydrogenation. Consequently the selectivity to cyclohexene hydrogenation was increased. Single-parameter correlations of log kvs.π* (dipolarity/polarizibility)... 

    Ionic liquid/graphene oxide as a nanocomposite for improving the direct electrochemistry and electrocatalytic activity of glucose oxidase

    , Article Journal of Solid State Electrochemistry ; Vol. 17, Issue 1 , January , 2013 , pp 183-189 ; ISSN: 1432-8488 Tasviri, M (Mahboubeh) ; Ghasemi, S. (Shahnaz) ; Ghourchian, H. (Hedayatollah) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
    By combination of 1-ethyl-3-methyl immidazolium ethyl sulfate as a typical room temperature ionic liquid (IL) and graphene oxide (GO) nanosheets, a nanocomposite was introduced for improving the direct electrochemistry and electrocatalytic activity of glucose oxidase (GOx). The enzyme on the IL–GO-modified glassy carbon electrode exhibited a quasireversible cyclic voltammogram corresponding to the flavine adenine dinucleotide/FADH2 redox prosthetic group of GOx. At the scan rate of 100 mV s−1, the enzyme showed a peak-to-peak potential separation of 82 mV and the formal potential of −463 mV (vs Ag/AgCl in 0.1 M phosphate buffer solution, pH 7.0). The kinetic parameters of the charge transfer... 

    Cross-linked basic nanogel; robust heterogeneous organocalayst

    , Article Chemical Engineering Journal ; Volume 232 , 2013 , Pages 453-457 ; 13858947 (ISSN) Pourjavadi, A ; Hosseini, S. H ; Emami, Z. S ; Sharif University of Technology
    A novel basic poly(ionic liquid) (PIL) was synthesized by miniemulsion polymerization of ionic liquid monomer 1-ethyl-3-vinylimidazolium bromide [EVim][Br] which was cross-linked by ionic liquid cross-linker 1,4-butanediyl-3,3'-bis-l-vinylimidazolium dibromide (BVD). Exchange of bromide anions in PIL nanogel with hydroxide, produced a supported basic ionic liquid catalyst. The catalytic performances of PIL nanogel with a size of about 200. nm was evaluated in the synthesis of 4. H-benzo[. b]pyrans by multi-component reaction in water. The present protocol represents a simple, ecologically safe and cost-effective route to synthesize 4. H-benzo[. b]pyrans with high products yield  

    Mesoporous silica-functionalized dual Brønsted acidic ionic liquid as an efficient catalyst for thioacetalization of carbonyl compounds in water

    , Article Catalysis Communications ; Volume 41 , 2013 , Pages 96-100 ; 15667367 (ISSN) Vafaeezadeh, M ; Dizicheh, Z. B ; Hashemi, M. M ; Sharif University of Technology
    A novel silica-functionalized dual Brønsted acidic ionic liquid (ionic liquid with two Brønsted acidic species) has been reported as a highly efficient catalyst for thioacetalization of carbonyl compounds. The reaction was efficiently performed in water as an environmentally benign solvent with good to high yields. Thermal gravimetric analysis showed that the catalyst is stable at least up to 350 C. Furthermore, the catalyst can be recycled and reused for six runs of reaction without appreciable loss of activity. The structure of the catalyst is modelized to gain more realistic structural insight about the functionalized ionic liquid  

    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
    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  

    Natural gas sweetening using ionic liquids, experiment and modeling

    , Article CHISA 2012 - 20th International Congress of Chemical and Process Engineering and PRES 2012 - 15th Conference PRES, 25 August 2012 through 29 August 2012 ; August , 2012 Safavi, M ; Ghotbi, C ; Jalili, A. H ; Taghikhani, V ; Sharif University of Technology
    A discussion covers the general descriptions and basic properties of ionic liquids (IL); main application areas, e.g., solvent replacement, purification of gases, homogenous and heterogeneous catalysis, biological reactions media, and removal of metal ions; and results of the research and works relating to gas solubility measurement and thermodynamic modeling of gas solubility with focus on acid gas solubility in IL. This is an abstract of a paper presented at the CHISA 2012 - 20th International Congress of Chemical and Process Engineering and PRES 2012 - 15th Conference on Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction (Prague, Czech Republic... 

    A non-cyanide route for glutaric acid synthesis from oxidation of cyclopentene in the ionic liquid media

    , Article Process Safety and Environmental Protection ; Volume 100 , 2016 , Pages 203-207 ; 09575820 (ISSN) Vafaeezadeh, M ; Hashemi, M. M ; Sharif University of Technology
    Institution of Chemical Engineers 
    The current work deals with the catalytic application of bis(1-butyl-3-methylimidazolium) tungstate ([BMIm]2WO4) for green synthesize of glutaric acid (GA) through oxidative cleavage of cyclopentene. In this method, 30% hydrogen peroxide (H2O2) was used as oxidant with water as the sole by-product of the reaction. Compared to the current synthetic procedures, this protocol is significantly improved in the environmental point of view. Moreover, the effect of the various parameters was investigated on the reaction efficiency. It was found that high yield of GA could obtain without using special methodologies or precautions. The catalytic system is reusable for several times  

    Surfactant-Like brønsted acidic ionic liquid as an efficient catalyst for selective mannich reaction and biodiesel production in water

    , Article Journal of the Iranian Chemical Society ; Volume 14, Issue 4 , 2017 , Pages 907-914 ; 1735207X (ISSN) Vafaeezadeh, M ; Karbalaie Reza, M ; Mahmoodi Hashemi, M ; Qasempour Soleimany, K ; Sharif University of Technology
    Springer Verlag  2017
    Abstract: The current study deals with the applications of a surfactant-like Brønsted acidic ionic liquid (IL) 1-dodecyl-3-methylimidazolium hydrogen sulfate ([DMIm]HSO4) for Mannich reaction at room temperature. The reaction was efficiently preceded in water as solvent without using any harmful and expensive organic additives. Our findings showed that the reaction is selective for cyclohexanone and no Mannich product was observed when cyclopentanone was used as starting material. Density functional theory (DFT) calculations were performed to provide an evidence about the nature of reactivity of the cyclohexanone/cyclopentanone. The activity of the catalyst was also tested for biodiesel... 

    Designed model for the Morita–Baylis–Hillman reaction mechanism in the presence of CaO and CaO modified with ionic liquid as a solid base catalyst: a DFT and MP2 investigation

    , Article Theoretical Chemistry Accounts ; Volume 137, Issue 9 , 2018 ; 1432881X (ISSN) Zobeydi, R ; Rahman Setayesh, S ; Sharif University of Technology
    Springer New York LLC  2018
    The new model for the Morita–Baylis–Hillman reaction based on the proton transfer were inquired by MP2 and DFT methods with 6-311G++(d, p) basis set combined with IEF-PCM solvent model. We focused on the reaction between acrylonitrile and benzaldehyde, catalyzed by CaO cluster and CaO modified with [Pyr][HSO4] ionic liquid. Our results indicate that in the presence of ionic liquid, the ionic liquid acts as a shuttle for the proton transfer between species in a lower energy pathway. The proton transfer step from enolate to catalyst is predicted to be the rate-limiting step for the whole process. In order to investigate the catalyst basicity, the pKa values of acrylonitrile and methyl acrylate... 

    Theoretical studies of the influence of protic and aprotic ionic liquids on the basicity of CaO as a solid base catalyst

    , Article Chemical Physics ; Volume 504 , 2018 , Pages 31-37 ; 03010104 (ISSN) Zobeydi, R ; Rahman Setayesh, S ; Sharif University of Technology
    Elsevier B.V  2018
    Proton affinity (PAs) and molecular basicities (GBs) of the CaO cluster and CaO modified with protic and aprotic ionic liquids in the gas phase have been calculated at the DFT/B3LYP level with a 6-311++G (d, p) basis set. The investigations of PAs and GBs in the solution phase have been studied by means of SCRF solvent effect computations using PCM solvation model for water solvent. The influence of the ILs cations and anions on the PA and GB in the gas phase and solution at the same level of theory has been investigated. We also studied the effect of [bmTr][NO3] ionic liquid on the basicity of CaO. The calculations display that this energetic ionic liquid has a high ability to improve the... 

    Hexyltriphenylphosphonium bromide as an absolutely chemoselective ionic liquid catalyst in the three-component reaction of aryl aldehydes, acetophenones and malononitrile

    , Article ChemistrySelect ; Volume 4, Issue 20 , 2019 , Pages 6190-6193 ; 23656549 (ISSN) Bahrami, K ; Khodaei, M. M ; Batooie, N ; Hosseinzadeh, N ; Foroumadi, A ; Sharif University of Technology
    Wiley-Blackwell  2019
    Hexyltriphenylphosphonium bromide (HTPB) is used as an efficient ionic liquid catalyst in the chemoselective addition of malononitrile to carbonyl group moiety of chalcones through the three-component reaction of aryl aldehydes, acetophenone derivatves, and malononitrile to produce (E)-2-(1,3-diarylallylidene)malononitriles at ambient temperature. The method is simple, solvent-free, environmentally friendly, and gives excellent yields in a short reaction times. © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim  

    Calixarene based ionic liquid as an efficient and reusable catalyst for one-pot multicomponent synthesis of polysubstituted pyridines and BIS-pyridines

    , Article ChemistrySelect ; Volume 4, Issue 19 , 2019 , Pages 5903-5910 ; 23656549 (ISSN) Alishahi, N ; Mohammadpoor Baltork, I ; Tangestaninejad, S ; Mirkhani, V ; Moghadam, M ; Kia, R ; Sharif University of Technology
    Wiley-Blackwell  2019
    In this work, a calixarene based ionic liquid was successfully prepared and characterized by different techniques. This ionic liquid was used as an efficient catalyst for the synthesis of a series of polysubstituted pyridines from aldehydes, malononitrile, 1,3-diketones and arylamines in water as a green solvent. Also, for the first time, symmetric and unsymmetric polysubstituted bis-pyridines were obtained in high yields from diamines using this catalyst. Mild reaction conditions, high to excellent yields, easy work-up, excellent activity and reusability of the catalyst are the key features of this method which make it an interesting and novel alternative for the synthesis of the above... 

    Magnetic metal nanoparticles decorated ionic liquid with excellent antibacterial activity

    , Article Journal of Nanostructures ; Volume 10, Issue 3 , 2020 , Pages 613-623 Salari, H ; Karimi Asl, M ; Padervand, M ; Gholami, M. R ; Sharif University of Technology
    University of Kashan  2020
    Fe3O4 magnetic structure was synthesized with co-precipitation method. Surface of magnetic core was modified with hydrophobic BMIM[PF6] ionic liquid. The samples became antibacterial by loading gold, copper and silver nanoparticles and denoted as Fe3O4/IL/X (X=Ag, Au, Cu). X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), thermal gravimetric analysis (TGA), Atomic absorption spectroscopy (AAS), Fourier transform infrared (FTIR) and vibration sample magnetometer (VSM) technics were applied for catalysts characterization, metal concentration analysis and morphology monitoring. Modified nanostructures were used for inactivation of Escherichia coli as... 

    Efficient fatty acid esterification using silica supported Brønsted acidic ionic liquid catalyst: Experimental study and DFT modeling

    , Article Chemical Engineering Journal ; Vol. 250 , 2014 , Pages 35-41 ; ISSN: 13858947 Vafaeezadeh, M ; Hashemi, M. M ; Sharif University of Technology
    A task-specific Brønsted acidic ionic liquid (BAIL), 1-benzyl-3-methylimidazolium hydrogensulfate ([BnMIm]HSO4), was prepared and confined onto the high surface area silica gel. The catalyst has shown extraordinary activity in comparison of homogeneous ionic liquid (IL) system for Fischer esterification of fatty acid with ethanol. The ester derivatives were synthesized in high yields and catalyst was easily separated from the reaction mixture by simple filtration. The structure of the catalyst is theoretically modelized to investigate the unusual catalytic activity. Hence, a hydroxylated cage-like nano-cluster, H6Si8O12(OH)2, was selected to mimic the surface of silica gel. The interactions... 

    Separation of CO2/CH4 through alumina-supported geminal ionic liquid membranes

    , Article Journal of Membrane Science ; Vol. 455 , 2014 , pp. 229-235 ; ISSN: 03767388 Shahkaramipour, N ; Adibi, M ; Seifkordi, A. A ; Fazli, Y ; Sharif University of Technology
    Interesting properties of ionic liquids lead to their application as sub-component of membrane structures. Supported ionic liquid membranes (SILMs) are porous membranes whose pores are saturated with ionic liquids. Two ionic liquids, pr[mim]2[Tf2N]2 [1,3-di(3-methyl-imidazolium) propane bis(trifluoromethylsulfonyl) imide] and, h[mim]2 [Tf2N]2 [(1,6-di(3-methylimidazolium)hexane bis(trifluoromethylsulfonyl)imide)], were synthesized in our laboratory and stabilized on an alumina porous support. Permeability and permselectivity of carbon dioxide and methane using membranes containing these ionic liquids were then measured. The experiments were performed in the pressure range of 10-50kPa and... 

    Design of silica supported task-specific ionic liquid catalyst system for oxidation of cyclohexene to adipic acid with 30% H 2O 2

    , Article Catalysis Communications ; Volume 26 , September , 2012 , Pages 54-57 ; 15667367 (ISSN) Vafaeezadeh, M ; Hashemi, M. M ; Shakourian Fard, M ; Sharif University of Technology
    Elsevier  2012
    1-Butyl-3-methylimidazolium tungstate ([BMIm] 2WO 4) ionic liquid supported onto silica sulphamic acid demonstrated desirable performance for oxidation of cyclohexene to adipic acid. Simple experimental procedure, easy product isolation, catalyst recovery and reusability are some attractive features of this protocol  

    Multi-Layer functionalized poly(ionic liquid) coated magnetic nanoparticles: Highly recoverable and magnetically separable brønsted acid catalyst

    , Article ACS Catalysis ; Volume 2, Issue 6 , 2012 , Pages 1259-1266 ; 21555435 (ISSN) Pourjavadi, A ; Hosseini, S. H ; Doulabi, M ; Fakoorpoor, S. M ; Seidi, F ; Sharif University of Technology
    A functionalized poly(ionic liquid) coated magnetic nanoparticle (Fe 3O 4@PIL) catalyst was successfully synthesized by polymerization of functionalized vinylimidazolium in the presence of surface modified magnetic nanoparticles. The resulting heterogeneous catalyst is shown to be an efficient acidic catalyst for synthesis of 1,1-diacetyl from aldehydes under solvent free conditions and room temperature in high yields. Also, the catalyst shows good activity for the deprotection reaction of acylals. After completion of reaction, the catalyst was simply recovered by an external conventional magnet and recycled without significant loss in the catalytic activity. Because of the polymer layers...