Über Eisen(III)-Komplexe mit Phenolen. IV. Säurekonstanten einiger Polyphenole

The apparent acid constants of some polyphenols and of derivates from salycilic acid are determined by potentiometry using glass or hydrogen electrodes and by UV spectrophotometry on comparable conditions respectively. Anaerobic manipulations were strictly used to avoid autoxidation. The results can be interpreted qualitatively, if the possibility of the formation of intramolecular hydrogen bridges is considered besides the effects of substituting groups.