Selective complexation of uranium(iii) over cerium(iii) by 2,6-bis(5,6-dialkyl-1,2,4-triazin-3-yl)pyridines: 1H NMR and X-ray crystallography studies

Abstract

Addition of 2,6-bis(5,6-dialkyl-1,2,4-triazin-3-yl)pyridines (btp) to UI₃ and CeI₃ in anhydrous pyridine gave the 1∶3 complexes [M(btp)₃]I₃, the terdentate nitrogen ligand being completely selective for U^III over Ce^III, as shown by ¹H NMR competition experiments; crystal structures of analogous btp complexes of U^III and Ce^III revealed that the U–N bond distances are significantly shorter than the corresponding Ce–N distances.