A cyclohexane-1,2-diyldinitrilotetraacetate tetrahydroxamate derivative for actinide complexation: synthesis and complexation studies

Abstract

A new tetrahydroxamate ligand has been synthesized and its chelating properties studied, in aqueous solutions, with thorium(IV) and iron(III) as analogues of the actinides plutonium(IV) and (to some extent) americium(III). The architecture of this ligand is based on that of the cyclohexane-1,2-diyldinitrilotetraacetate complexone with hydroxamate instead of carboxylate groups. It has proven to form quite stable and water soluble complexes with these metal ions, up to pH 9. Besides the 1∶1 (M∶L) monomeric species formed under acidic conditions, the corresponding (2∶2) dimeric complexes may also be admitted under physiological conditions. According to the magnetic properties and modelling calculations, the iron(III) dimer species should have some magnetic interaction between the metallic centres.