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RESEARCH PRODUCT

A solution study of complex formation between iron(III) and oxalate in dimethylsulphoxide

Francesc LloretJulio LatorreMigueli JulveMiguel MollarJuan FausIsabel Castro

subject

Oxalic acidInorganic chemistryMetals and Alloyschemistry.chemical_elementDiprotic acidOxalateInorganic ChemistrySolventchemistry.chemical_compoundchemistryMaterials ChemistryChemical stabilityCarboxylateCyclic voltammetryPlatinum

description

The complex formation between iron(III) and oxalic acid (ethanedioic acid, H2ox) has been studied by potentiometry in dimethylsulphoxide (dmso) solution. H2ox behaves as a weak diprotic acid in such a solvent, with overall association constants: log βj1=8.551(3) and log βj2=14.242(3) at 25°C and 0.1 Mn-Bu4NClO4. A reliable set of overall stability constants for the iron(III)-oxalato complexes, log β11=13.16(4), log β12=23.66(4) and log β13=30.75(4), have been obtained for the first time under identical conditions. The electrochemical behaviour of such complexes was studied in dmso at a platinum electrode. The coordination ability of oxalate towards iron(III) in dmso and water media is compared and discussed in the light of thermodynamic and structural parameters.

https://doi.org/10.1007/bf01127866