A phenanthroline-derived ligand and its complexation with Pd(ii): from ligand design, synthesis and Pd(ii) complexes structures to its application

摘要

A novel phenanthroline-derived bis-opened-triazine ligand for selective complexation with Pd( II ) over 19 typical metals from HNO _(3) media was designed based on cavity modulation strategy. Structures of the three species of the Pd( II ) complexes of with the ligand were elucidated by ~(1) H NMR titration isothermal titration calorimetry (ITC) and density functional theory (DFT) studies. ITC test and binding energy calculations demonstrated that the asymmetrical 1?:?1 Pd( II )–ligand complex with a monodentate nitrate anion was the most stable among these three species of the Pd( II ) complexes. The excellent kinetics of Pd( II ) extraction with the ligand is due to its optimal conformation completely ready for metal ligation. The enhanced special extraction selectivity and fast extraction rate towards Pd( II ) achieved by the phenanthroline-derived ligand demonstrated that the effective separation of some radionuclides with smaller radius in HLW through cavity modulation strategy is a feasible approach.