title: The influence of linker geometry in bis(3-hydroxy-N-methyl-pyridin-2-one) ligands on solution phase uranyl affinity.
abstract: Seven water-soluble, tetradentate bis(3-hydroxy-N-methyl-pyridin-2-one) (bis-Me-3,2-HOPO) ligands were synthesized that vary only in linker geometry and rigidity. Solution-phase thermodynamic measurements were conducted between pH 1.6 and pH 9.0 to determine the effects of these variations on proton and uranyl cation affinity. Proton affinity decreases by introduction of the solubilizing triethylene glycol group as compared to unsubstituted reference ligands. Uranyl affinity was found to follow no discernable trends with incremental geometric modification. The butyl-linked 4 li-Me-3,2-HOPO ligand exhibited the highest uranyl affinity, consistent with prior in vivo decorporation results. Of the rigidly-linked ligands, the o-phenylene linker imparted the best uranyl affinity to the bis-Me-3,2-HOPO ligand platform.
authors.affiliation: Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.
authors.forename: Géza
authors.initials: G
authors.lastname: Szigethy
authors.forename: Kenneth N
authors.initials: KN
authors.lastname: Raymond