Temperature and substituent effects on the dissociation constants of some 5-( p-substituted phenylazo) barbituric acid compounds

The dissociation constants of the title compounds were determined potentiometrically in the range 25–40 ° C. The thermodynamic quantities Δ H, Δ G and Δ S were evaluated. The variation in the p K values were ascribed to the differences in the chemical potentialities of the substituents. The imide-im...

Full description

Saved in:
Bibliographic Details
Published in:Thermochimica acta 1988-12, Vol.136, p.1-6
Main Authors: Masoud, M.S., Soliman, E.M., Elkholy, A.E., Khalil, E.A.
Format: Article
Language:English
Subjects:
Chemical reactivity
Chemistry
Exact sciences and technology
Organic chemistry
Reactivity and mechanisms
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The dissociation constants of the title compounds were determined potentiometrically in the range 25–40 ° C. The thermodynamic quantities Δ H, Δ G and Δ S were evaluated. The variation in the p K values were ascribed to the differences in the chemical potentialities of the substituents. The imide-imidol tautomerism in the barbituric acid nuclei was visualized. Trials to correlate the values of p K with ν(NN) were made.
ISSN:0040-6031
1872-762X
DOI:10.1016/0040-6031(88)87421-5