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

Molecules

Haydar Yüksek²  Zafer Ocak²  Muzaffer Alkan²  Şule Bahi¹ 

[1] Fatih Education Faculty, Karadeniz Technical University, 61335 Trabzon, Turkey.;Department of Chemistry, Kafkas University, 36100 Kars, Turkey; Fax [phone].

关键词: 4;    5-Dihydro-1H-1;    2;    4-triazol-5-ones;    acylation;    acidity;    potentiometric titration;    syntheses;   

DOI  :  10.3390/90400232

来源: mdpi

【 摘 要 】

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 pK_a values were determined for all cases.

【 授权许可】

Unknown   
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