The protonation constants of some aliphatic alkylamines in ethanol-water mixtures


Kilic E., Gokce G., Canel E.

Turkish Journal of Chemistry, vol.26, no.6, pp.843-849, 2002 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 26 Issue: 6
  • Publication Date: 2002
  • Journal Name: Turkish Journal of Chemistry
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, TR DİZİN (ULAKBİM)
  • Page Numbers: pp.843-849
  • Keywords: aliphatic amines, potentiometry, protonation constant, ethanol-water mixtures, NON-AQUEOUS MEDIA, SUBSTITUTED SALICYLIDENEANILINES, RELATIVE BASICITIES, AMINES, TITRATIONS, SOLVENT
  • Ankara University Affiliated: Yes

Abstract

Protonation constants of methyl-, ethyl-, propyl- and butylamines were determined potentiometrically using an electrode system calibrated in concentration units of hydrogen ion in ethanol-water mixtures (10% -80% ethanol, v/v) at an ionic strength of 0.1 and ar 25°C. The trend in the values of protonation constants of these aliphatic amines was explained in terms of the number of alkyl groups and solvent composition. The basicity orders were found to be NH3 < R3N < RNH2 < R2NH (R:-CH3, -C2H5, -n-C3H7 and -n-C4H9) in all the solvent mixtures studied.