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    Palladium-catalyzed carbamate-directed regioselective halogenation: A route to halogenated anilines

    , Article Journal of Organic Chemistry ; Volume 81, Issue 9 , 2016 , Pages 3868-3876 ; 00223263 (ISSN) Matloubi Moghaddam, F ; Tavakoli, G ; Saeednia, B ; Langer, P ; Jafari, B ; Sharif University of Technology
    American Chemical Society  2016
    This study describes an efficient method for ortho-selective halogenation of N-arylcarbamates under mild conditions for the first time. Although being weakly coordinating, N-arylcarbamates act very well as a removable directing group for activation of C-H bonds. The developed procedure results in extremely valuable halogenated N-arylcarbmates that can further be hydrolyzed to halogenated anilines. The obtained reaction conditions showed broad scope and wide functional group tolerance. All the products were formed in good yields with extremely high selectivity  

    Metal promoted mordenite catalyst for methanol conversion into light olefins

    , Article Petroleum Science and Technology ; Vol. 32, Issue. 11 , 2014 , Pages 1349-1356 ; ISSN: 10916466 Shareh, F. B ; Kazemeini, M ; Asadi, M ; Fattahi, M ; Sharif University of Technology
    Methanol conversion was investigated on dealuminated mordenite (DM) as well as a series of promoted DM (i.e., metal/DM) catalysts prepared by impregnation. Prepared catalysts characterized by the powder XRD, BET, and NH3-TPD techniques. Chemical analysis was performed using induced coupled plasma (ICP) method. The conversion of methanol over different metal/mordenite catalysts was compared at 460C and WHSV of 1 h-1. Several metals including Fe, La, and Ca had been used to prepare metal/DM catalysts, which displayed high selectivity toward propylene production. Ultimately, La/DM catalyst was determined to be the best material amongst those investigated for methanol conversion based upon its... 

    Oxido-peroxido W(VI)-histidine–MgAl-layered double hydroxide composite as an efficient catalyst in sulfide oxidation

    , Article Applied Organometallic Chemistry ; Volume 32, Issue 6 , 2018 ; 02682605 (ISSN) Nikkhoo, M ; Amini, M ; Morteza, S ; Farnia, F ; Bayrami, A ; Bagherzadeh, M ; Gautam, S ; Chae, K. H ; Sharif University of Technology
    John Wiley and Sons Ltd  2018
    Oxido-peroxido W(VI)-histidine–MgAl-layered double hydroxide composite was prepared by using MgAl-layered double hydroxide as a host and oxido-peroxido W(VI)-histidine complex as a guest. The composite was characterized by XRD, IR, EDX,SEM and TEM techniques. This composite is tested for catalytic selective sulfoxidation reactions using hydrogen peroxide as oxidant showing good to moderate conversion along with high selectivity. Copyright © 2018 John Wiley & Sons, Ltd  

    Activation of CX (=Cl, Br) bond in aryl halides toward the palladium-catalyzed Heck reaction using 2,6-bis(diphenylphosphino)pyridine

    , Article Journal of Molecular Catalysis A: Chemical ; Volume 366 , January , 2013 , Pages 30-35 ; 13811169 (ISSN) Ataei, A ; Nadri, S ; Rafiee, E ; Jamali, S ; Joshaghani, M ; Sharif University of Technology
    The 2,6-bis(diphenylphosphino)pyridine/palladium catalytic system successfully catalyzes the Heck coupling reaction of less reactive aryl chlorides as well as aryl bromides with styrene to give the corresponding olefins in reasonable yields. TBAB (tetrabutylammoniumbromide) as an additive was found to be essential for these reactions. The results of Heck reaction exhibited a high selectivity (>99/1) favoring the trans product  

    Synthesis of “L-cysteine–graphene oxide” hybrid by new methods and elucidation of its uptake properties for Hg(II) ion

    , Article Separation Science and Technology (Philadelphia) ; Volume 53, Issue 6 , 2018 , Pages 843-855 ; 01496395 (ISSN) Daneshmand, M ; Outokesh, M ; Akbari, A ; Kosari, M ; Tayyebi, A ; Sharif University of Technology
    Taylor and Francis Inc  2018
    This study introduces two new, simple, and scalable methods for synthesis of “cysteine–graphene oxide” hybrid, namely nucleophilic and covalent methods. Produced adsorbents could uptake 500 and 600 mg Hg2+/g, respectively, which are larger than capacities of most of the commercial adsorbents. By means of different instrumental techniques, chemical structures of the obtained graphene products were disclosed, and two pertinent mechanisms for their formations were suggested. Time for attaining uptake equilibrium for nucleophilic/covalent samples was 30 min/150 min, and kinetics was controlled by liquid film resistance/chemical reaction mechanisms, respectively. High selectivity and good... 

    Application of Cardo-type polyimide (PI) and polyphenylene oxide (PPO) hollow fiber membranes in two-stage membrane systems for CO2/CH4 separation

    , Article Journal of Membrane Science ; Volume 324, Issue 1-2 , 2008 , Pages 85-94 ; 03767388 (ISSN) Pourafshari Chenar, M ; Soltanieh, M ; Matsuura, T ; Tabe Mohammadi, A ; Sadeghi, M ; Sharif University of Technology
    Elsevier B.V  2008
    In this study, a two-stage membrane system for the separation of CH4/CO2 was designed based on a series of laboratory-scale experiments obtained using two types of commercial hollow fiber membranes including polyphenylene oxide (PPO) and Cardo-type polyimide (PI). The former showed high permeability and low to moderate selectivity, while the latter exhibited high selectivity and moderate permeability. In this design, the permeate from the first stage - rich in CO2 but containing considerable amount of methane - is fed into the second stage to recover its methane content. The performances of double- and single-stage system designs were compared in terms of methane loss (the ratio of methane... 

    Nano cobalt-copper ferrite catalyzed regioselective α-C(sp3)–H cyanation of amines: Secondary, tertiary, and drug molecules

    , Article Catalysis Communications ; Volume 149 , 2021 ; 15667367 (ISSN) Matloubi Moghaddam, F ; Pourkaveh, R ; Heidarian, M ; Sharif University of Technology
    Elsevier B.V  2021
    Oxidative cyanation of sp3C–H bonds at the α position of amines was achieved using CoCuFe2O4 as a catalyst and NaCN as an inexpensive cyanide source at room temperature. CoCuFe2O4 was found to be an active catalyst for Csp [3]-Csp coupling, efficiently delivering valuable α-aminonitriles from tertiary/secondary amines in good yields. The corresponding products were obtained with high selectivity toward α position. In addition, functional group tolerance offered the opportunity for application in late-stage functionalization of biologically active molecules. This transformation proceeds convenient on a gram-scale, and the catalyst can be reused for several runs with consistent catalytic... 

    Electrodeposition and electrocatalytic properties of Pt/Ni-Co nanowires for non-enzymatic glucose detection

    , Article Journal of Alloys and Compounds ; Volume 554 , 2013 , Pages 169-176 ; 09258388 (ISSN) Mahshid, S. S ; Mahshid, S ; Dolati, A ; Ghorbani, M ; Yang, L ; Luo, S ; Cai, Q ; Sharif University of Technology
    A nanowire arrays system consisting of an ordered configuration of Pt, Ni and Co was constructed in single-bath solution through pulse electrodeposition. This structure was evaluated as a potential amperometric non-enzymatic sensor to detect glucose in alkaline solution. We observed a strong and fast amperometric response at low applied potential of 0.4 V vs. SCE over linear ranges of 0-0.2 mM and 0.2-8 mM glucose with sensitivities of 1125 and 333 μA mM-1 cm-2, respectively. We also observed a low detection limit for glucose of 1 μM. Correlation of the electronic and geometric modifications with the electrochemical performance characteristics enhanced catalytic activity of the electrode by... 

    A well-dispersed Pt/Ni/TiO 2 nanotubes modified electrode as an amperometric non-enzymatic glucose biosensor

    , Article Sensor Letters ; Volume 9, Issue 5 , October , 2011 , Pages 1598-1605 ; 1546198X (ISSN) Mahshid, S. S ; Luo, S ; Yang, L ; Mahshid, S ; Dolati, A ; Ghorbani, M ; Cai, Q ; Sharif University of Technology
    In this study a novel Pt/Ni nanostructure consisting of nano-bushes and nanocubes was fabricated onto TiO 2 nanotubes. The scanning electron microscopy images showed that a large amount of well-dispersed nano-architectures had uniformly covered all over the surface which made an electrode with high surface area. It was obviously seen that the nanocube structures mainly consists of Ni had been grown on top of each other while the Pt colonies represented bush-like structures. As a non-enzymatic glucose biosensor, the Pt/Ni TiO 2 nanotubes modified electrode exhibited an excellent performance. The proposed biosensor had two linear ranges for detection of glucose from 0 to 0.12 mM (correlation... 

    Power of a remote hydrogen bond donor: Anion recognition and structural consequences revealed by IR spectroscopy

    , Article Journal of Organic Chemistry ; Volume 80, Issue 2 , December , 2015 , Pages 1130-1135 ; 00223263 (ISSN) Samet, M ; Danesh Yazdi, M ; Fattahi, A ; Kass, S. R ; Sharif University of Technology
    American Chemical Society  2015
    Natural and synthetic anion receptors are extensively employed, but the structures of their bound complexes are difficult to determine in the liquid phase. Infrared spectroscopy is used in this work to characterize the solution structures of bound anion receptors for the first time, and surprisingly only two of three hydroxyl groups of the neutral aliphatic triols are found to directly interact with Cl-. The binding constants of these triols with zero to three CF3 groups were measured in a polar environment, and KCD3CN(Cl-) = 1.1 × 106 M-1 for the tris(trifluoromethyl) derivative. This is a remarkably large value, and high selectivity with respect to interfering anions such as, Br-, NO3 -... 

    Synthesis, structural characterization and alcohol oxidation activity of a new mononuclear manganese(II) complex

    , Article Transition Metal Chemistry ; Volume 35, Issue 3 , 2010 , Pages 297-303 ; 03404285 (ISSN) Najafpour, M. M ; Amini, M ; Bagherzadeh, M ; Boghaei, D. M ; McKee, V ; Sharif University of Technology
    A manganese(II) complex of 2,4,6-tris(2-pyridyl)-1,3,5-triazine (tptz) has been synthesized and characterized by single-crystal X-ray diffraction, elemental analyses, IR, and UV-Vis spectroscopic techniques. Oxidation of alcohols to their corresponding aldehydes and ketones was conducted by this catalyst using oxone (2KHSO5KH-SO4K2SO4) as an oxidant under biphasic reaction conditions (CH2Cl2/H 2O) and tetra-n-butylammonium bromide as phase transfer agent under air at room temperature. Easy preparation, mild reaction conditions, high yields of the products, short reaction times, no further oxidation to the corresponding carboxylic acids, high selectivity and inexpensive reagents make this... 

    Polymeric mixed matrix membranes containing zeolites as a filler for gas separation applications: A review

    , Article Journal of Industrial and Engineering Chemistry ; Volume 19, Issue 2 , 2013 , Pages 375-393 ; 1226086X (ISSN) Bastani, D ; Esmaeili, N ; Asadollahi, M ; Sharif University of Technology
    Polymeric membrane technology has received extensive attention in the field of gas separation, recently. However, the tradeoff between permeability and selectivity is one of the biggest problems faced by pure polymer membranes, which greatly limits their further application in the chemical and petrochemical industries. To enhance gas separation performances, recent works have focused on improving polymeric membranes selectivity and permeability by fabricating mixed matrix membranes (MMMs). Inorganic zeolite materials distributed in the organic polymer matrix enhance the separation performance of the membranes well beyond the intrinsic properties of the polymer matrix. This concept combines... 

    Synthesis, X-ray structure, characterization and catalytic activity of a polymeric manganese(II) complex with iminodiacetate

    , Article Applied Organometallic Chemistry ; Volume 25, Issue 7 , 2011 , Pages 559-563 ; 02682605 (ISSN) Bagherzadeh, M ; Amini, M ; Boghaei, D. M ; Najafpour, M. M ; McKee, V ; Sharif University of Technology
    A polymeric manganese(II) complex with the general formula [Mn(O 2CCH2NH2CH2CO2) 2(H2O)2]n from reaction of iminodiacetatic acid and manganese(II) perchlorate under nitrogen in water, was synthesized and characterized. The structure of the complex was determined using single-crystal X-ray diffraction, elemental analysis, IR and UV-vis spectra. This complex exhibited excellent catalytic activity and selectivity for oxidation of various alcohols and sulfides to the corresponding aldehydes/ketone and sulfoxides using urea hydrogen peroxide and oxone (2KHSO 5·KHSO4·K2SO4), respectively, as oxidants under air at room temperature. The easy preparation, mild reaction conditions, high yields of the... 

    Effect of CVD parameters on hydrogen permeation properties in a nano-composite SiO 2-Al 2O 3 membrane

    , Article Journal of Membrane Science ; Volume 423-424 , 2012 , Pages 530-535 ; 03767388 (ISSN) Amanipour, M ; Ganji Babakhani, E ; Safekordi, A ; Zamaniyan, A ; Heidari, M ; Sharif University of Technology
    Tubular ceramic membranes were synthesized by depositing a dense layer of silica-alumina on top of a multilayer substrate using co-current chemical vapor deposition (CVD) method. The multilayer substrate was prepared by coating with a series of bohemite sols with certain particle sizes. Cross-sectional and surface images obtained from high resolution FESEM showed that the intermediate layer had a thickness of about 1μm and the top selective layer was uniform and dense with a thickness of less than 100nm. Permeance tests, which were carried out with H 2, CO 2, N 2 and CH 4 at a high temperature range of 923-1073K, indicated that gas permeation took place via different mechanisms through...