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    Synthesis of β-hydroxy dithiocarbamate derivatives via regioselective addition of dithiocarbamate anion to epoxide in water

    , Article Canadian Journal of Chemistry ; 2006, 84, 1515-1519 Ziyaei-Halimjani, A. (Azim) ; Saidi, M. R ; Sharif University of Technology
    Abstract
    The reactions of different dithiocarbamate anions with epoxides were investigated in water. With this method, β-hydroxy dithiocarbamate derivatives were synthesized in high yields. The reaction was also carried out in DMF in the presence of lithium perchlorate with a simple work-up procedure, and the results are compared  

    One-pot Three-component route for the synthesis of functionalized 4H-chromenes catalyzed by ZrOCl2·8H2O in water

    , Article Journal of Heterocyclic Chemistry ; Volume 55, Issue 2 , 2018 , Pages 522-529 ; 0022152X (ISSN) Ziyaei Halimehjani, A ; Keshavarzi, N ; Sharif University of Technology
    HeteroCorporation  2018
    Abstract
    An efficient method for the synthesis of functionalized 4H-chromenes via a one-pot three-component condensation reaction of a 2-hydroxybenzaldehyde with an active methylene compound and a carbon-based nucleophile in the presence of a catalytic amount of ZrOCl2·8H2O in water under thermal condition has been described. High yields, simple work-up procedure, performing reactions in water and synthesis of complex molecules with a one-pot procedure are the main advantages of this procedure. In addition, the structure of the product from the condensation of salicylaldehyde, 2-naphthol, and dimedone was confirmed by X-ray crystallography. © 2018 Wiley Periodicals, Inc  

    The chemistry of 2-hydroxy-β-nitrostyrenes: versatile intermediates in synthetic organic chemistry

    , Article Organic and Biomolecular Chemistry ; Volume 21, Issue 13 , 2023 , Pages 2653-2688 ; 14770520 (ISSN) Ziyaei Halimehjani, A ; Ghaffari, Z ; Sharif University of Technology
    Royal Society of Chemistry  2023
    Abstract
    The applications of 2-hydroxy-β-nitrostyrenes as efficient bifunctional intermediates in organic synthesis are investigated in this review. For this purpose, reactions of 2-hydroxy-β-nitrostyrenes with diverse molecules, including carbonyl compounds, 1,3-dicarbonyl compounds, α,β-unsaturated carbonyl compounds, hemiacetals, nitroalkenes, γ-butenolides, tetronic acid, azalactones, pyrazolones, enamines, malononitrile, methyleneindolinones, ylides, etc., were investigated to construct interesting biologically active scaffolds such as chromans, chromenes, coumarins, benzofurans and their fused and spiro rings, natural products, and other useful cyclic and acyclic compounds. The main focus is on... 

    Synthesis of aza-Henry products and enamines in water by Michael addition of amines or thiols to activated unsaturated compounds

    , Article Tetrahedron Letters ; Volume 49, Issue 7 , 2008 , Pages 1244-1248 ; 00404039 (ISSN) Ziyaei Halimehjani, A ; Saidi, M. R ; Sharif University of Technology
    2008
    Abstract
    Nitroamines and nitrothiols were synthesized in high yields by the Michael addition of amines and thiols to nitroolefins without using any catalyst. Also, the reaction of amines with dimethylacetylene dicarboxylate (DMAD) in water afforded the corresponding enamines. © 2007 Elsevier Ltd. All rights reserved  

    Synthesis of β-hydroxy dithiocarbamate derivatives via regioselective addition of dithiocarbamate anion to epoxide in water

    , Article Canadian Journal of Chemistry ; Volume 84, Issue 11 , 2006 , Pages 1515-1519 ; 00084042 (ISSN) Ziyaei Halimjani, A ; Saidi, M. R ; Sharif University of Technology
    2006
    Abstract
    The reactions of different dithiocarbamate anions with epoxides were investigated in water. With this method, β-hydroxy dithiocarbamate derivatives were synthesized in high yields. The reaction was also carried out in DMF in the presence of lithium perchlorate with a simple work-up procedure, and the results are compared. © 2006 NRC  

    An efficient one-pot Michael addition of dithiocarbamate anion to α,β-unsaturated olefins mediated by lithium perchlorate

    , Article Journal of Sulfur Chemistry ; Volume 26, Issue 2 , 2005 , Pages 149-153 ; 17415993 (ISSN) Ziyaei-Halimjani, A ; Saidi, M. R ; Sharif University of Technology
    Taylor and Francis Ltd  2005
    Abstract
    The reaction of substituted dithiocarbamates with electrophilic alkenes in the presence of LiClO4 was investigated in an attempt to prepare numerous ethyl dithiocarbamates bearing β-electron-withdrawing-group substituents. The reaction conditions are mild, neutral, with extremely simple work-up procedures, and offer high yield. © 2005 Taylor & Francis Group Ltd  

    Chemoselective and convenient preparation of 1,1-diacetates from aldehydes, mediated by solid lithium perchlorate under solvent-free conditions

    , Article Journal of Molecular Catalysis A: Chemical ; Volume 238, Issue 1-2 , 2005 , Pages 138-141 ; 13811169 (ISSN) Ziyaei, A ; Azizi, N ; Saidi, M. R ; Sharif University of Technology
    2005
    Abstract
    A simple, efficient, and general method has been developed for the conversion of aldehydes to 1,1-diacetates with the use of acetic anhydride and solid LiClO4 under first solvent-free and mild conditions in good yields. This method applies to not only simple but also to conjugated aldehydes. © 2005 Elsevier B.V. All rights reserved  

    Investigating Mechanism, Transition State, and Products Distribution of Catalys-Free Hydrothiolation Reactions of Unactivated Terminal Alkynes by Dithiocarbamic Acids

    , M.Sc. Thesis Sharif University of Technology Kolivand, Mohammad (Author) ; Ziyaei Halimehjani, Azim (Supervisor)
    Abstract
    In this study, catalyst-free hydrothiolation reactions of unactivated terminal alkynes by dithiocarbamic acids have been investigated via computational chemistry approach and by Gaussian 09, GaussVeiw 5.0, and Spartan '14 V1.1.4 software from the perspective of the reaction mechanism, transition state, and the distribution of products. The calculation results have shown that the various in situ produced dithiocarbamic acids addition to unactivated terminal alkynes in which the alkyl group attached to the carbon 2 is an aliphatic hydrocarbon alkyl is through Markovnikov type path and this product is thermodynamically more stable which is in agreement with the experimental results. The NBO... 

    Catalyst-free regioselective ring opening of epoxides with aromatic amines in water and solvent-free conditions

    , Article Journal of the Iranian Chemical Society ; Volume 10, Issue 1 , February , 2013 , Pages 7-11 ; 1735207X (ISSN) Ziyaei Halimehjani, A ; Gholami, H ; Saidi, M. R ; Sharif University of Technology
    2013
    Abstract
    Without using any catalysts, a variety of epoxides undergo ring-opening by aromatic amines to afford the corresponding 1,2-amino alcohols in high to excellent yields with good regioselectivity in the presence of water as solvent and under solvent-free conditions  

    Highly efficient and catalyst-free synthesis of unsymmetrical thioureas under solvent-free conditions

    , Article Tetrahedron Letters ; Volume 50, Issue 1 , 2009 , Pages 32-34 ; 00404039 (ISSN) Ziyaei Halimehjani, A ; Pourshojaei, Y ; Saidi, M. R ; Sharif University of Technology
    2009
    Abstract
    A highly efficient and simple synthesis of unsymmetrical thioureas is reported based on the reaction of readily synthesized dithiocarbamates with amines, without using any catalyst under solvent-free conditions. The short reaction time, high yields, and solvent-free conditions are advantages of this method. We did not observe the formation of any symmetric disubstituted thiourea, under these reaction conditions. © 2008 Elsevier Ltd. All rights reserved  

    Regiospecific iodocyclization of S-allyl dithiocarbamates: synthesis of 2-imino-1,3-dithiolane and 2-iminium-1,3-dithiolane derivatives

    , Article Tetrahedron Letters ; Volume 50, Issue 23 , 2009 , Pages 2747-2749 ; 00404039 (ISSN) Ziyaei Halimehjani, A ; Maleki, H ; Saidi, M. R ; Sharif University of Technology
    2009
    Abstract
    4-Alkyl-2-imino-1,3-dithiolanes and 4-alkyl-2-iminium-1,3-dithiolanes were prepared in excellent yields with complete regiospecificity under mild conditions by the iodocyclization of S-allyl dithiocarbamates. Dehydrohalogenation of the 4-alkyl-2-imino-1,3-dithiolanes gave 4-alkylidene-2-imino-1,3-dithiolanes in excellent yields. © 2009 Elsevier Ltd. All rights reserved  

    Catalyst-free Friedel-Crafts alkylation of naphthols with nitrostyrenes in the presence of water

    , Article Tetrahedron Letters ; Volume 50, Issue 13 , 2009 , Pages 1441-1443 ; 00404039 (ISSN) Ziyaei Halimehjani, A ; Aryanasab, F ; Saidi, M. R ; Sharif University of Technology
    2009
    Abstract
    Accelerated Michael-type Friedel-Crafts alkylation of naphthols with nitrostyrenes in the presence of water is reported. The procedure is simple, catalyst-free, and affords good yields of the products. © 2009 Elsevier Ltd. All rights reserved  

    Minimizing the levelized cost of energy in an offshore wind farm with non-homogeneous turbines through layout optimization

    , Article Ocean Engineering ; Volume 249 , 2022 ; 00298018 (ISSN) Ziyaei, P ; Khorasanchi, M ; Sayyaadi, H ; Sadollah, A ; Sharif University of Technology
    Elsevier Ltd  2022
    Abstract
    Minimum cost of energy is the main goal of a wind farm layout optimization. This is achieved by maximizing the total energy while minimizing the total costs of the farm. In this study, two sizes of commercial turbines were considered to investigate the effect of a non-homogenous farm on the layout optimization process. A cost model consisting of turbines, cable, transformers, foundation, and service vehicle routes was developed. Using Genetic Algorithm and Artificial Neural Network, first the superiority of the new algorithm in turbines and cable layout was verified versus previous studies. Next, two cases were investigated, i.e. (1) a farm populated with identical turbines and (2) a farm... 

    Offshore Windfarm Layout Optimization

    , M.Sc. Thesis Sharif University of Technology Ziyaei, Pegah (Author) ; Khorasanchi, Mahdi (Supervisor) ; Sayyadi, Hassan (Co-Supervisor)
    Abstract
    The minimum cost of energy is the goal of the wind farm layout optimization. This can be achieved by either maximizing the total energy or minimizing the total costs of the farm. This thesis considered the effect of wind speed on the performance and thrust coefficients. We also used two sizes of commercial turbines. First, we started by a single variable objective function (turbine cost to generated power), then, considering cable, foundation and O&M modules, objective function changed to a LCOE function which is non-dimensionalized by dividing all the costs to the cost of one turbine. We modified the simple cost model proposed by Mosetti et al., using cost scaling law, and also included... 

    Reductive amination of aldehydes with sodium borohydride and lithium aluminum hydride in the presence of lithium perchlorate

    , Article Journal of the Iranian Chemical Society ; Volume 4, Issue 2 , 2007 , Pages 194-198 ; 1735207X (ISSN) Saidi, M. R ; Brown, R. S ; Ziyaei Halimjani, A ; Sharif University of Technology
    Iranian Chemical Society  2007
    Abstract
    A one-pot high yielding reductive amination of aldehydes with primary and secondary amines using LiClO4/NaBH4 and LiClO 4/LiAlH4 as reducing agents in diethyl ether is described  

    Investigation of the Reaction of Dithiocarbamic Acid Salts with Fluorinating Agents

    , M.Sc. Thesis Sharif University of Technology Farhang, Amir Mohammad (Author) ; Ziyaei Halimejani, Azim (Supervisor)
    Abstract
    Dithiocarbamates have demonstrated extensive applications as synthetic intermediates in the synthesis of functional groups and heterocyclic rings. These compounds, due to their high nucleophilicity, are capable of reacting with a wide range of electrophiles, including aldehydes, alkyl halides, azo compounds, diazo compounds, and many others, yielding diverse and valuable products. This project aims to investigate the reaction of dithiocarbamate salts with fluorinating agents for the synthesis of thiocarbamoyl fluorides. Initially, dithiocarbamate salts were prepared via the reaction of amines with carbon disulfide and the presence of an inorganic base, followed by their conversion to target... 

    Dithiocarbamates as an efficient intermediate for the synthesis of 2-(alkylsulfanyl)thiazoles in water

    , Article Tetrahedron Letters ; Volume 57, Issue 8 , 2016 , Pages 883-886 ; 00404039 (ISSN) Ziyaei Halimehjani, A ; Hasani, L ; Ali Alaei, M ; Saidi, M.R ; Sharif University of Technology
    Elsevier Ltd  2016
    Abstract
    A simple, green and high-yielding procedure for the synthesis of 4-substituted-2-(alkylsulfanyl)thiazoles from the reaction of dithiocarbamates and α-halocarbonyl containing compounds in water is described. Also, a one-pot, two-step procedure for the synthesis of 2-(alkylsulfanyl)thiazoles from acetophenone and dithiocarbamates was developed. © 2016 Elsevier Ltd. All rights reserved  

    A simple and novel eco-friendly process for the synthesis of cyclic dithiocarbonates from epoxides and carbon disulfide in water

    , Article Journal of Heterocyclic Chemistry ; Volume 46, Issue 2 , 2009 , Pages 347-350 ; 0022152X (ISSN) Ziyaei Halimehjani, A ; Ebrahimi, F ; Azizi, N ; Saidi, M. R ; Sharif University of Technology
    2009
    Abstract
    The reaction of oxiranes with carbon disulfide for preparation of cyclic dithiocarbonates was carried out in water under catalytic amount of an organic base such as dimethylaminopyridine or triethylamine. The reaction conditions are simple and give high yields of desired products.© 2009 HeteroCorporation  

    Investigation of the reaction of dithiocarbamic acid salts with aromatic aldehydes

    , Article Organic Letters ; Volume 14, Issue 15 , July , 2012 , Pages 3838-3841 ; 15237060 (ISSN) Ziyaei Halimehjani, A ; Hajiloo Shayegan, M ; Hashemi, M. M ; Notash, B ; Sharif University of Technology
    ACS  2012
    Abstract
    A reaction of dithiocarbamic acid salts with carbonyl compounds was investigated for the first time in the presence of BF 3•OEt 2. The reaction is temperature dependent and gives gem-bis(dithiocarbamates) at 35-45 °C as a molecule with high equivalents of dithiocarbamate groups. At lower temperatures (15-20 °C), the 2-iminium-1,3-dithietane is obtained as the only product. The structure of a 2-iminium-1,3-dithietane was accomplished by X-ray crystallographic analysis  

    One-pot synthesis of dithiocarbamates accelerated in water

    , Article Journal of Organic Chemistry ; Volume 71, Issue 9 , 2006 , Pages 3634-3635 ; 00223263 (ISSN) Azizi, N ; Aryanasab, F ; Torkiyan, L ; Ziyaei, A ; Saidi, M. R ; Sharif University of Technology
    2006
    Abstract
    Highly efficient one-pot reactions of amines and carbon disulfide with α,β-unsaturated compounds were carried out in water under a mild and green procedure with high yields. © 2006 American Chemical Society