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    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 Harifi-Mood, A. R. (Ali Reza) ; 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... 

    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 , 2011 , Pages 185-190 ; 05388066 (ISSN) Harifi Mood, A. R ; Rahmati, M ; Gholami, M. R ; 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... 

    Polar and low polar solvents media effect on dipole moments of some diazo Sudan dyes

    , Article Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy ; Vol. 127 , 2014 , Pages 340-348 ; ISSN: 13861425 Zakerhamidi, M. S ; Golghasemi Sorkhabi, Sh ; Shamkhali, A. N ; Sharif University of Technology
    Abstract
    Absorption and fluorescence spectra of three Sudan dyes (Sudan III, SudanIV and Sudan black B) were recorded in various solvents with different polarity in the range of 300-800 nm, at room temperature. The solvatochromic method was used to investigate dipole moments of these dyes in ground and excited states, in different media. The solvatochromic behavior of these substances and their solvent-solute interactions were analyzed via solvent polarity parameters. Obtained results express the effects of solvation on tautomerism and molecular configuration (geometry) of Sudan dyes in solvent media with different polarity. Furthermore, analyze of solvent-solute interactions and value of ground and... 

    Synthesis and properties of novel fluorinated polyamides based on noncoplanar sulfoxide containing aromatic bis(ether amine)

    , Article Polymer Journal ; Volume 41, Issue 3 , 2009 , Pages 174-180 ; 00323896 (ISSN) Shockravi, A ; Abouzari Lotf, E ; Javadi, A ; Taheri, S ; Sharif University of Technology
    2009
    Abstract
    A novel sulfoxide containing bis(ether amine) monomer, 2,2'-sulfoxide- bis[4-methyl(2-trifluoromethyl)4-aminophenoxy) phenyl ether] (M2), was synthesized from the halogen displacement of 2-chloro-5-nitrobenzotrifluoride with dibenzosulfoxide (DH) in the presence of potassium carbonate, followed by catalytic reduction of bis(ether nitro) intermediate with Zinc/Ammonium chloride. A series of organic-soluble poly(ether amide)s (PA1-7) bearing sulfoxide and electronwithdrawing trifiuoromethyl group were synthesized from bis(ether amine) with various aromatic diacids (1-7) via a direct polycondensation with triphenyl phosphite and pyridine. The resulting polymers had inherent viscosities ranging...