title: Synthesis and determination of pKa values of some new 3,4-disubstituted-4,5-dihydro-1H-1,2,4-triazol-5-one derivatives in non-aqueous solvents.
abstract: 3-Alkyl(Aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones (2) reacted with 2-furoyl chloride and thiophene-2-carbonyl chloride to afford the corresponding 3- alkyl(aryl)-4-(2-furoylamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (3) and 3-alkyl(aryl)- 4-(2-thienylcarbonylamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones (4), respectively. The new compounds synthesized were characterized by using IR, 1H-NMR, 13C-NMR and UV spectral data together with elemental analysis. In addition, to investigate the effects of solvents and molecular structure upon acidity, compounds 3 and 4 were titrated potentiometrically with tetrabutylammonium hydroxide in four non-aqueous solvents (isopropyl alcohol, tert-butyl alcohol, N,N-dimethylformamide and acetonitrile). The half-neutralization potential values and the corresponding pKa values were determined for all cases.
authors.affiliation: Department of Chemistry, Kafkas University, 36100 Kars, Turkey. hyuksek98@yahoo.com
authors.forename: Haydar
authors.initials: H
authors.lastname: Yüksek
authors.forename: Zafer
authors.initials: Z
authors.lastname: Ocak
authors.forename: Muzaffer
authors.initials: M
authors.lastname: Alkan
authors.forename: Sule
authors.initials: S
authors.lastname: Bahçeci
authors.forename: Mustafa
authors.initials: M
authors.lastname: Ozdemir
mesh_terms: D000818:Animals; D006863:Hydrogen-Ion Concentration; D015394:Molecular Structure; D012997:Solvents / Q000737:chemistry*; D014230:Triazoles / Q000138:chemical synthesis / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D012997:Solvents; D014230:Triazoles; D014867:Water