CMPO-functionalized C3-symmetric tripodal ligands in liquid/liquid extractions: efficient, selective recognition of Pu(IV) with low affinity for 3+ metal ions.

Structural modifications of carbamoylmethylphosphine oxide (CPMO)-functionalized triphenoxymethane platforms are described, and the influence of these changes on the ability of the ligand to extract actinides from simulated acidic nuclear waste streams has been evaluated. The ligand system has been shown to have excellent binding efficiency and a selectivity for An(IV) in comparison to the a simple monomeric CMPO ligand under analogous conditions. Both the extraction efficiency and selectivity are strongly dependent on the flexibility and electronic properties of the ligating units in the triphenoxymethane construct. The Tb(III) and Bi(III) nitrate complexes of tris-CMPO derivatives have been isolated, and their structures were elucidated by NMR, ESI FT-ICR MS, and X-ray analysis, providing information on the interactions between metal ions and the tris-CMPO molecules.

Highly efficient binding of trivalent f-elements from acidic media with a C3-symmetric tripodal ligand containing diglycolamide arms.

Tripodal chelates bearing three diglycolamide units precisely arranged on a triphenoxymethane platform were synthesized to mimic the preferred tricapped trigonal prismatic geometry favored by lanthanides with oxygen donor ligands, and the ligand binds heavier lanthanides very efficiently in acidic media.