Synthesis and Non-Aqueous Medium Titrations of Some New 4‑Benzylidenamino-4,5-dihydro-1H-1,2,4-triazol-5-one Derivatives

Molecules

Haydar Yüksek¹  Osman Üçüncü²  Muzaffer Alkan¹  Zafer Ocak¹ 

[1] Education Faculty, Kafkas University, 36100 Kars, Turkey; Fax [phone];Department of Chemistry, Kafkas University, 36100 Kars, Turkey

关键词: 4;    5-Dihydro-1H-1;    2;    4-triazol-5-one;    Schiff base;    acidity;    potentiometric titrations;    methylation;    acetylation;   

DOI  :  10.3390/10080961

来源: mdpi

【 摘 要 】

The synthesis of 3-alkyl(aryl)-4-(3-ethoxy-4-hydroxybenzylidenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones 3 from the reactions of 3-alkyl(aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones 2 with 3-ethoxy-4-hydroxybenzaldehyde is described. The acetylation and methylation reactions of the compounds 3 giving compounds of type 4 and 5, respectively, were investigated. The newly synthesized compounds were characterized using elemental analyses and IR, ¹H-NMR, ¹³C-NMR and UV spectral data. In addition, to investigate the effects of solvents and molecular structure upon acidity, compounds 3 were titrated potentiometrically with tetrabutylammonium hydroxide in four non-aqueous solvents (isopropyl alcohol, tert-butyl alcohol, acetonitrile and N,N-dimethylformamide). 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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