Design of lanthanide based metal–organic polyhedral cages for application in catalysis, sensing, separation and magnetism

Lanthanide organic polyhedral cage complexes are a class of supramolecular compounds that present exciting opportunities in applications ranging from sensing to catalysis and magnetism. Metal organic polyhedra incorporating transition metal vertices bridged by organic ligands have been extensively studied. By contrast analogous lanthanide complexes, which present additional benefits beyond those of their transition metal counterparts, remain an underrepresented class of supramolecule. One unique property of lanthanide organic cages is the luminescence properties bestowed by the metal ions which offer interesting opportunities in imaging applications, whilst the large ionic radii of the trivalent ions enables the formation of novel structures with opportunities to incorporate ancillary ligands not possible for transition metal structures. This review summarizes the key developments in synthesis and characterization of lanthanide metal organic cages, allowing general structural trends to emerge and highlights the exciting applications already demonstrated for these complexes.