Spectrofluorimetric and Potentiometric Determination of Acidity Constants of 4-(4'-Acetyloxy-3'-Methoxybenzylidene)-5-Oxazolone Derivatives


TOPKAYA TAŞKIRAN D., ÖZTÜRK ÜRÜT G., Ayata S., ALP S.

JOURNAL OF FLUORESCENCE, vol.27, no.2, pp.521-528, 2017 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 27 Issue: 2
  • Publication Date: 2017
  • Doi Number: 10.1007/s10895-016-1979-9
  • Journal Name: JOURNAL OF FLUORESCENCE
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.521-528
  • Keywords: Oxazolones, Fluorescence, Acidity constant, Solution media, Titration, PK(A) VALUES, FLUORESCENCE EMISSION, NONAQUEOUS MEDIA, BINARY-MIXTURES, SCHIFF-BASES, TITRATIONS
  • Dokuz Eylül University Affiliated: Yes

Abstract

4-(4'-acetyloxy-3'-methoxybenzylidene)-5-oxazolone fluorescent molecules bearing four different aryl groups attached to the 2-position of 5-oxazolone ring have been investigated by spectrophotometric and potentiometric techniques in solution media. The acidity constants (pKa) of the fluorescent molecules were precisely determined in acetone, acetonitrile, dimethylformamide and in 1:1 mixture of toluene-isopropanol. The studied derivatives were titrated with tetrabutylammonium hydroxide and non-aqueous perchloric acid by scanning the basic and acidic region of the pH scale. A computerizable derivative method was used in order to descript precisely the end point and pKa values. The molecules investigated performed well-shaped and stoichiometric potentiometric titration curves.