Abstract
Acid dissociation constants and partition coefficients of N-phenyl-β-mercaptocinnamamide (I), N-ethyl-β-mercaptocinnamamide (II) and monothiodibenzoylmethane (III) were determined by the solvent extraction method in various solvent systems, by the use of 35S-labeled species of these chelating agents. The results are considerably different from those obtained spectrophotometrically. The hydrolysis and the oxidation were found to occur in aqueous organic solvent in parallel with the dissociation in I and II, and III respectively. The solvent extraction method was regarded to be preferable than the spectrophotometric method, because the influences of the side reactions can be made very little by the use of solvent extraction method.
