Behaviour of some newly synthesized substituted 1,2,4-triazoline-3-thiones in sulfuric acid media


  • Mirjana Jankulovska Institute of Chemistry, Faculty of Natural Sciences and Mathematics, Ss. Cyril & Methodius University, Skopje,
  • Ilinka Spirevska Institute of Chemistry, Faculty of Natural Sciences and Mathematics, Ss. Cyril & Methodius University, Skopje,
  • Katica Čolančevska-Ragenović Faculty of Technology and Metallurgy, Ss. Cyril & Methodius University, Skopje,



4-butyl-5-octyl-2, 4-dihydro-3H-1, 2, 4-triazoline-3-thione, 4-allyl-5-octyl-2, 4-triazoline- 3-thione, 4-phenyl-5-octyl2, 4-dihydro3H-1, UV spectrophotometry, protonation constants


The protonation process of some newly synthesized substituted 1,2,4-triazoline-3-thiones (4-butyl-5-octyl-2,4- dihydro-3H-1,2,4-triazoline-3-thione, 4-allyl-5-octyl-2,4-dihydro-3H-1,2,4-triazoline-3-thione, 4-phenyl-5-octyl-2,4- dihydro-3H-1,2,4-triazoline-3-thione) was investigated in aqueous sulfuric acid solutions, using the ultraviolet spectrophotometric method, at a room temperature. The acid-base equillibria were characterized qualitatively and quantitatively. The method of characteristic vector analysis (CVA) was used to reconstruct the experimental spectra. The protonation process, most likely occurs on the thiourea fragment of the 1,2,4-triazoline-3-thione ring. The pKBH + values were calculated using several methods: the Hammett acidity function method, Bunnett and Olsen, Tissier and Tissier (Bunnett and Olsen, Yates), Marziano, Cimino and Passerini, and the “Excess acidity" function method (Cox and Yates). There is a good agreement between the pKBH + values determined with these different methods.


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How to Cite

Jankulovska, M., Spirevska, I., & Čolančevska-Ragenović, K. (2006). Behaviour of some newly synthesized substituted 1,2,4-triazoline-3-thiones in sulfuric acid media. Macedonian Journal of Chemistry and Chemical Engineering, 25(1), 29–37.