Terpyridine-Functionalized TentaGel Microbeads: Synthesis, Metal Chelation and First Sequential Complexation

The functionalization of polystyrene/poly-(ethylene glycol) TentaGel® microbeads (d = 20 μm) with 2,2′:6′,2″-terpyridine units is described resulting in a material with easily accessible ligands which possess an excellent affinity for transition metal ions. The subsequent loading with different metal ions via metal-to-ligand complexation yielded the corresponding Co^II, Ni^II, Fe^II, and Cu ^II modified beads. The isolated materials were investigated in detail utilizing UV/vis spectroscopy, optical microscopy, atomic absorption spectroscopy (AAS), scanning electron microscopy (SEM), and atomic force microscopy (AFM). Moreover, grafting of free terpyridine moieties via ruthenium(II)/ruthenium(III)-chemistry onto the beads is demonstrated. This opens-up new pathways for the selective modification of such microbeads and the preparation of functional materials.