SELECTIVITY AMONG, AND AGGREGATION OF, LANTHANIDE IONS

Ligands that show selectivity towards, and aggregation of, lanthanides are of intrinsic interest in coordination chemistry. We have shown th at Schiff base and amine phenolate ligands exhibit a variety of coordi nation modes in lanthanide(III) complexes, and that tren-(tris((2-amin o)ethyl)amine)-based amine phenolates show selectivity towards later l anthanide(III) ions. By altering the nature of the amine phenolate lig and backbone the coordination mode of the ligand in solution can be ea sily controlled. Selectivity among lanthanide(III) ions can be control led by substitution of the parent ligand donor atoms (phenolate oxygen ) with donor atoms of a different type (e.g. phosphinate oxygen). By d erivatizing the ligand to include more donor atoms and by stiffening t he backbone, it is possible to control the aggregation of lanthanide(I II) ions (enabling the formation of dimeric lanthanide complexes).