Iron(III) complexes of sugar-type ligands

A series of iron(III) complexes formed with sugartype ligands (aldoses, ketoses, polyalcohols, sugar acids, di- and trisaccharides) was prepared. The composition of the complexes was determined by standard analytical methods. It was shown that deprotonated alcoholic hydroxy groups participate in the complex formation and polynuclear species are formed. Mössbauer spectra reflected the presence of high spin iron(III) central atoms. EPR spectra showed antiferromagnetic interactions between the iron(III) centres in the complexes indicating dimeric or oligomeric complex structures. The ratio of interacting and isolated iron(III) atoms depend on the nature of the ligand and on the preparation mode of the complexes (metal-to-ligand ratio, pH, diamagnetic dilution, etc.).