EFFECT OF CHANGING pH UPON THE RATE AND MECHANISM OF DECARBOXYLATION OF SUBSTITUTED ANTHRANILIC ACIDS
Year: 1965
Type: article
Abstract: The ionization constants of 4-methoxyanthranilic acid have been determined spectrophotometrically in water at 60 °C and ionic strength 0.10. The variation in rate of decarboxylation with varying pH at constant ionic strength has been measured at 90 °C with 4-methylanthranilic acid and at 60 °C with 4-methoxyanthranilic acid. With each acid the maximum rate occurs at a pH about 2 units less than the isoelectric pH. To account for these results it is necessary to postulate an equilibrium between at least two intermediates formed by protonation of the 1-position of the aromatic ring. One of these must be formed from the anion and the other(s) by protonation of neutral acid and (or) zwitterion.
Source: Canadian Journal of Chemistry
DOI: 10.1139/v65-425
Authors: G. E. Dunn, P. Leggate, I. E. Scheffler
Institution: University of Manitoba
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W1979594115