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Lithium perchlorate-catalyzed three-component coupling: a facile and general method for the synthesis of α-aminophosphonates under solvent-free conditions
, Article European Journal of Organic Chemistry ; Issue 23 , 2003 , Pages 4630-4633 ; 1434193X (ISSN) ; Saidi, M. R ; Sharif University of Technology
Wiley-VCH Verlag
2003
Abstract
A simple, efficient, and general method has been developed for the synthesis of α-aminophosphonates in the presence of solid lithium perchlorate under solvent-free conditions. Thus secondary and tertiary α-aminophosphonates were synthesized relatively quickly in good yields at room temperature. © Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003
Solvent effects on kinetics of an heteroatomic nucleophilic substitution reaction in ionic liquid and molecular solvents mixtures
, Article Russian Journal of Physical Chemistry A ; Volume 87, Issue 12 , December , 2013 , pp 1969-1975 ; 1531-863X ; Pedervand, M. (Mohsen) ; Sadeghzadeh-Darabi, F. (Faramarz) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
Abstract
Rate constants, k A, for the aromatic nucleophilic substitution reaction of 2-chloro-3,5-dinitropyridine with aniline were determined in different compositions of 2-propanol mixed with hexane, benzene, and 2-methylpropan-2-ol and 1-ethyl-3-methylimidazolium ethylsulfate ([Emim][EtSO4]) with dimethyl sulfoxide at 25°C. The obtained rate constants of the reaction in pure solvents are in the following order: 2-methylpropan-2-ol > dimethyl sulfoxide > 2-propanol > hexane > benzene > [Emim][EtSO4]. Molecularmicroscopic solvent parameters corresponding to the selected binary mixtures were utilized to study the kinetics of a nucleophilic substitution reaction in order to investigate and compare the...
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 ; Padervand, M. (Mohsen) ; Gholami, M. R. (Mohammad Reza) ; Hallett, Jason P ; Sharif University of Technology
Abstract
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...
Tandem dinucleophilic cyclization of cyclohexane-1,3-diones with pyridinium salts
, Article Beilstein Journal of Organic Chemistry ; Volume 9 , 2013 , Pages 1119-1126 ; 18605397 (ISSN) ; Moghaddam, F. M ; Mkrtchyan, S ; Semeniuchenko, V ; Supe, L ; Villinger, A ; Langer, P ; Laroshenko, V. O ; Sharif University of Technology
2013
Abstract
The cyclization of cyclohexane-1,3-diones with various substituted pyridinium salts afforded functionalized 8-oxa-10-aza-tricyclo[7.3.1.0 2,7]trideca-2(7),11-dienes. The reaction proceeds by regioselective attack of the central carbon atom of the 1,3-dicar-bonyl unit to 4-position of the pyridinium salt and subsequent cyclization by base-assisted proton migration and nucleophilic addition of the oxygen atom to the 2-position, as was elucidated by DFT computations. Fairly extensive screening of bases and additives revealed that the presence of potassium cations is essential for formation of the product
The performance of phthalimide-N-oxyl anion
, Article Monatshefte fur Chemie ; Volume 137, Issue 12 , 2006 , Pages 1591-1595 ; 00269247 (ISSN) ; Moghaddam, F. M ; Saeidian, H ; Mallakpour, S ; Sharif University of Technology
2006
Abstract
Alkali metal salts of phthalimide-N-oxyl, including Li, Na, and K were prepared and applied as novel selective catalysts to promote the cyclotrimerization of aryl and alkyl isocyanates. This paper is addressing these salts as a new class of organic nucleophilic catalysts. © Springer-Verlag 2006
A novel and simple solvent free method for nucleophilic aromatic substitution of inactive aryl halides
, Article Synthetic Communications ; Volume 34, Issue 15 , 2004 , Pages 2783-2787 ; 00397911 (ISSN) ; Akhbari, M ; Sharif University of Technology
2004
Abstract
A simple, high yield, and short time method for nucleophilic displacement reaction of inactive aryl halides is reported. The reaction is performed in microwave oven under thermal condition with montmorillonite supported AgNO 3
A facile synthesis of bridged polycyclic naphthooxazocine skeletons: Eight-membered-ring constructions via tandem dinucleophilic addition of naphthalenols to quinolinium salts
, Article Helvetica Chimica Acta ; Volume 94, Issue 1 , 2011 , Pages 142-147 ; 0018019X (ISSN) ; Taheri, S ; Mirjafary, Z ; Saeidian, H ; Kiamehr, M ; Tafazzoli, M ; Sharif University of Technology
2011
Abstract
The efficient synthesis of bridged polycyclic naphthooxazocines 3 via addition of naphthalenols 1 as a bis-nucleophile to N-alkylquinolinium salts 2 is described (Scheme 1 and Table 2). This new approach provides a powerful entry into polycyclic structures containing bicyclic N,O-acetals related to bioactive compounds
Reaction kinetics investigation of 1-fluoro-2,4-dinitrobenzene with substituted anilines in ethyl acetate–methanol mixtures using linear and nonlinear free energy relationships
, Article Journal of Physical Organic Chemistry ; Volume 24, Issue 11 , November , 2011 , pages 1095–1100 ; Harifi-Mood, A. R. (Ali Reza) ; Gholami, M. R. (Mohammad Reza) ; Sharif University of Technology
Abstract
Aromatic nucleophilic substitution reaction of 1-fluoro-2,4-dinitrobenzene with para-substituted and meta-substituted anilines was kinetically investigated in the mixtures of ethyl acetate and methanol at room temperature. The correlation of second-order rate coefficients with Hammett's substituent constants yields a fairly linear straight line with negative slope in different mole fractions of ethyl acetate–methanol mixtures. The measured rate coefficients of the reaction demonstrated a dramatic variation in ethyl acetate–methanol mixtures with the increasing mole fraction of ethyl acetate. Linear free energy relationship (LFER) investigations confirm that polarity has a major effect on the...
Dithiocarbamic acids and thiols as nucleophiles in the Bargellini reaction
, Article Scientia Iranica ; Volume 19, Issue 3 , June , 2012 , Pages 551-554 ; 10263098 (ISSN) ; Saidi, M. R ; Sharif University of Technology
2012
Abstract
Dithiocarbamic acids and thiols are employed in the Bargellini reaction to generate useful intermediates for the synthesis of organic molecules. This is the first time that dithiocarbamic acids are used as nucleophile in this reaction
Theoretical study of kinetics and mechanism of reactions of hydroxylamine and amineoxide anion with methyl iodide in gas and aqueous phases
, Article Progress in Reaction Kinetics and Mechanism ; Volume 32, Issue 1 , 2007 , Pages 29-50 ; 14686783 (ISSN) ; Irani, M ; Gholami, M. R ; Sharif University of Technology
Science Reviews Ltd
2007
Abstract
The kinetics and mechanism of the reactions of hydroxylamine and aminoxide anion with methyl iodide were studied with ab initio calculations, Monte-Carlo and QM/MM simulations in gas and aqueous phases. Geometrical parameters and charge calculations show that these reactions proceed through the SN2 (bimolecular nucleophilic displacement) mechanism only. The solvent effects on these reactions were studied by inserting water molecules in reaction media, Onsager model, Monte-Carlo and QM/MM simulations. Activation parameters indicate the expected variation in activation energy and rate coefficient in aqueous phase in comparison to the gas phase. The shift of potential energy barrier through the...
Solvent effects on kinetics of an heteroatomic nucleophilic substitution reaction in ionic liquid and molecular solvents mixtures
, Article Russian Journal of Physical Chemistry A ; Volume 87, Issue 12 , 2013 , Pages 1969-1975 ; 00360244 (ISSN) ; Pedervand, M ; Sadeghzadeh Darabi, F ; Gholami, M. R ; Sharif University of Technology
2013
Abstract
Rate constants, k A, for the aromatic nucleophilic substitution reaction of 2-chloro-3,5-dinitropyridine with aniline were determined in different compositions of 2-propanol mixed with hexane, benzene, and 2-methylpropan-2-ol and 1-ethyl-3-methylimidazolium ethylsulfate ([Emim][EtSO4]) with dimethyl sulfoxide at 25 C. The obtained rate constants of the reaction in pure solvents are in the following order: 2-methylpropan-2-ol > dimethyl sulfoxide > 2-propanol > hexane > benzene > [Emim][EtSO4]. Molecularmicroscopic solvent parameters corresponding to the selected binary mixtures were utilized to study the kinetics of a nucleophilic substitution reaction in order to investigate and compare the...
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, Issue 2 , 2013 , Pages 157-170 ; 14686783 (ISSN) ; Hallett, J. P ; Padervand, M ; Gholami, M. R ; Sharif University of Technology
2013
Abstract
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]BF 4) 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...
Solvent polarity and hydrogen bond effects on nucleophilic substitution reaction of 2-bromo-5-nitrothiophene with piperidine
, Article International Journal of Chemical Kinetics ; Volume 43, Issue 4 , April , 2011 , pages 185–190 ; Rahmati, M. (Masoud) ; Gholami, M . R. (Mohammad Reza) ; Sharif University of Technology
Abstract
The reaction kinetics of 2-bromo-5-nitro thiophene with piperidine was studied in a solvent with a mixture of propan-2-ol with methanol and n-hexane at 25°C. The measured rate coefficients of the reaction demonstrated dramatic variations in propan-2-ol–n-hexane mixtures and mild variations in propan-2-ol–methanol system. The second-order rate coefficients of the reaction, kA, decreased sharply with n-hexane content. The multiparameter correlation of log kA versus molecular-microscopic solvent parameters shows interesting results in these solutions. Linear free energy relationship investigations confirm that polarity has a major effect on the reaction rate and hydrogen bond ability of the...
Pyridinium salts - Versatile reagents for the regioselective synthesis of functionalized thiazocino[2,3-b]indoles by tandem dinucleophilic reactions of thiooxindoles
, Article Tetrahedron ; Volume 68, Issue 47 , 2012 , Pages 9685-9693 ; 00404020 (ISSN) ; Moghaddam, F. M ; Gormay, P. V ; Semeniuchenko, V ; Villinger, A ; Langer, P ; Iaroshenko, V. O ; Sharif University of Technology
2012
Abstract
The reaction of thiooxindoles with various 2- and 3-substituted pyridinium salts afforded a variety of functionalized thiazocinoindoles. The products have been prepared in good to excellent yields by regioselective dinucleophilic C/S-cyclocondensation of thiooxindoles with pyridinium salts
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) ; 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
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) ; 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...
Regiochemistry of nucleophilic substitution of pentachloropyridine with N and O bidentate nucleophiles
, Article New Journal of Chemistry ; Volume 39, Issue 6 , 2015 , Pages 4398-4406 ; 11440546 (ISSN) ; Ranjbar Karimi, R ; Kia, R ; Sharif University of Technology
Royal Society of Chemistry
2015
Abstract
Site reactivity of some enol-imines derived from N-aryl formamides with pentachloropyridine under basic conditions in dry CH3 CN was investigated. The aromatic nucleophilic substitution of pentachloropyridine with enol-imines occurs at the 4-position of pyridine ring by both oxygen and nitrogen site of enol-imines. Nucleophilic attack by the oxygen of enol-imine gave corresponding oximino compounds as a mixture of E- and Z-isomers. In contrast, nucleophilic attack by the nitrogen of enol-imine gave the unexpected N,N-di-substituted aryl compounds. The structures of all the compounds were confirmed by IR, 1H NMR, 13C NMR and 19F NMR spectroscopy as well as elemental analysis and...
Influence of Intramolecular Hydrogen Bonding on Ability of Leaving Group in SN2 Reactions
, M.Sc. Thesis Sharif University of Technology ; Fattahi, Alireza (Supervisor)
Abstract
Many of the significant reactions in chemistry and biology are related to bimolecular nucleophilic substitution (SN2) reactions which have been studied first by Hughes and Ingold in the 1930s. Afterward, many organic chemists have continued this work. Up to now, numerous experimental kinetic and theoretical researches have studied the mechanism of these reactions. Since most SN2 reactions occur in solution, a large number of these studies have been devoted to the solvent effects. One of these effects that has been examined extremely is H-bonding via protic solvents that lowers the energy of an anionic nucleophile relative to the transition state, in which the charge is more diffuse, and...
Solvatochromic Parameters Effects Study on Kinetics of Aromatic Nucleophilic substitution reaction in mixture of Ionic liquid and alcoholic solvents
, M.Sc. Thesis Sharif University of Technology ; Gholami, Mohammad Reza (Supervisor)
Abstract
Solute-solvent and solvent-solvent interactions were investigated in mixtures of 2-hydroxy ethylammonium formate with methanol, ethylene glycol and glycerol. Solvatochromic parameters, including normalized polarity ( ), dipolarity/polarizability (π*), hydrogen-bond donor (α), and hydrogen-bond acceptor (β) abilities, were determined in these mixtures. parameters showed synergetic effects in mixtures of ionic liquid and alcohols due to the preferential solvation. Experimental data were handled in Redlich-Kister model and demonstrated a fair correlation with predicted data. Solvent effects on reaction kinetics were studied in aromatic nucleophilic substitution reaction of 2-Chloro-3,5-...
Reaction kinetics investigation of 1-fluoro-2,4-dinitrobenzene with substituted anilines in ethyl acetate-methanol mixtures using linear and nonlinear free energy relationships
, Article Journal of Physical Organic Chemistry ; Volume 24, Issue 11 , 2011 , Pages 1095-1100 ; 08943230 (ISSN) ; Harifi Mood, A. R ; Gholami, M. R ; Sharif University of Technology
Abstract
Aromatic nucleophilic substitution reaction of 1-fluoro-2,4-dinitrobenzene with para-substituted and meta-substituted anilines was kinetically investigated in the mixtures of ethyl acetate and methanol at room temperature. The correlation of second-order rate coefficients with Hammett's substituent constants yields a fairly linear straight line with negative slope in different mole fractions of ethyl acetate-methanol mixtures. The measured rate coefficients of the reaction demonstrated a dramatic variation in ethyl acetate-methanol mixtures with the increasing mole fraction of ethyl acetate. Linear free energy relationship (LFER) investigations confirm that polarity has a major effect on the...