Oxydoreduction and Complex Formation Between Fe³⁺ Ions and Acetylacetonedioxime

Abstract

The reactions between Fe 3+ ions and acetylacetonedioxlme (AADO) have been studied by potentiometric, polarographic and spectrophotometric methods. Two Fel+ ions are reduced in aqueous solution by one AADOmolecule to give Fe 2+ ions and the oxidized form of AADO(NPO= AADO-2e = 2-nitrosopent-2-en-4-one oxime). NPO forms a water soluble, red coloured complex with FeOlI). The synthesiS of bis(2-nitrosopent-2-en-4-one oximato) Fe(III) complex is described. The elemental analysis of the solid complex is consistent with the composition FeO(NP0>Z<0H). The IR, EPR and Mossbauer spectra of the cOIDplex are presented and the bonding properties of the coordination environment of Fe(IIO is discussed. A mechanism for the oxydoreducnon and complexation reactions for the Fe 3+'AAOOsystem is proposed and its kinetic parameters are: k ox. red. =1.72 x 10 -I min -1, kcompl.= 5.13 10-2 min~l.