Isaac Scientific Publishing

Modern Organic Chemistry Research

Determination of Dissociation Constants of Some Novel Tetrahydropyrimidine Derivatives in Mixed Organic-Water System by Simple pH Measurement

Download PDF (451.1 KB) PP. 25 - 32 Pub. Date: February 14, 2017

DOI: 10.22606/mocr.2017.21005


  • Shipra Baluja*
    Physical Chemistry Laboratory, Department of Chemistry, Saurashtra University, Rajkot-360005 (Gujarat), India.
  • Kapil D. Bhesaniya

    Physical Chemistry Laboratory, Department of Chemistry, Saurashtra University, Rajkot-360005 (Gujarat), India.
  • Ashish B. Patel

    Physical Chemistry Laboratory, Department of Chemistry, Saurashtra University, Rajkot-360005 (Gujarat), India.


Some tetrahydropyrimidine derivatives have been synthesized and their structures have been confirmed by IR, 1H NMR, 13C NMR and mass spectral data. The dissociation constants of these derivatives of tetrahydropyrimidine have been measured by Calvin Bjerrum pH titration method in DMF-water (60: 40 v/v) system at 303.15 K. It is observed that dissociation constant depends on substituent groups present in the compounds.


Tetrahydropyrimidine derivatives, dissociation constant, DMF-water system, Calvin Bjerrum pH titration method


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