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

Harifi Mood, A. R ; Sharif University of Technology | 2006

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  1. Type of Document: Article
  2. DOI: 10.3184/007967406779946937
  3. Publisher: Science Reviews Ltd , 2006
  4. Abstract:
  5. 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 bond donor acidity of media demonstrate opposite effects on the reaction rate. The dipolarity/polarisability of media has a positive effect regarding to zwitterionic character of the reaction intermediate and the hydrogen bond donor acidity shows a negative effect because of hydrogen-bonding interactions between aniline and solvent molecules. © 2006 Science Reviews
  6. Keywords:
  7. Alcohols ; Aniline ; Organic solvents ; Rate constants ; Reaction kinetics ; Substitution reactions ; Aromatic nucleophilic substitution reactions ; Room temperature ; Solute-solvent interactions ; Solvent effects ; Amines
  8. Source: Progress in Reaction Kinetics and Mechanism ; Volume 31, Issue 2 , 2006 , Pages 117-127 ; 14686783 (ISSN)
  9. URL: https://journals.sagepub.com/doi/10.3184/007967406779946937?icid=int.sj-abstract.similar-articles.2