Microwave-Assisted Synthesis of Novel 2,4-Dihydro-5-[4-(trifluoromethyl)phenyl]-3H-1,2,4-triazol-3-ones and Potentiometric Determination of Their pK(a) in Nonaqueous Solvents


ÖZİL M., İSLAMOĞLU F., MENTEŞE E., Kahveci B.

HELVETICA CHIMICA ACTA, vol.93, no.10, pp.1967-1974, 2010 (Journal Indexed in SCI) identifier

  • Publication Type: Article / Article
  • Volume: 93 Issue: 10
  • Publication Date: 2010
  • Title of Journal : HELVETICA CHIMICA ACTA
  • Page Numbers: pp.1967-1974

Abstract

The novel 4-amino- or 4-aryl-substituted 2,4-dihydro-5-[(4-trifluoromethyl)phenyl]-3H-1,2,4-triazol-3-ones 3a-3g were synthesized by reaction of N-(ethoxycarbonyl)-4-(trifluoromethyl)benzenehydrazonic acid ethyl ester (2) and primary amines or hydrazine by microwave irradiation. Compounds 3a-3g were potentiometrically titrated with tetrabutylammonium hydroxide (Bu4NOH) in four nonaqueous solvents, i.e., (PrOH)-Pr-i, (BuOH)-Bu-i, MeCN, and N,N-dimethylformamide (DMF). Also half-neutralization potential values and the corresponding pK(a) values were determined in all cases.