Iron(III) and Proton Associations with Some Singly Substituted Phenolate Ions in Aqueous Solution

Abstract

In an earlier study (1) in which the stabilities of 1:1 iron(III)-phenolate complexes were measured in aqueous solution for phenol and several singly substituted para or meta derivatives, an approximately linear relation was observed to exist between the free energies for the association reactions:

$${\text{F}}{{\text{e}}^{{\text{3 + }}}}\;{\text{ + }}\;{\text{O}}{{\text{C}}_{\text{6}}}{{\text{H}}_{\text{4}}}{{\text{X}}^{\text{ - }}}\; \rightleftarrows \;{\text{FeO}}{{\text{C}}_{\text{6}}}{{\text{H}}_{\text{4}}}{{\text{X}}^{{\text{2 + }}}}$$

(1)

$${{\text{H}}^{\text{ + }}}\;{\text{ + }}\;{\text{O}}{{\text{C}}_{\text{6}}}{{\text{H}}_{\text{4}}}{{\text{X}}^{\text{ - }}}\; \rightleftarrows \;{\text{HO}}{{\text{C}}_{\text{6}}}{{\text{H}}_{\text{4}}}{\text{X}}$$

(2)