Identification of Seven-coordinate LnIII Ions in a LnIII[15-MCFeIIIN(shi)-5](OAc)2Cl Species Crystallized from Methanol and Pyridine

The title metallacrown (MC) complexes LnIII[15-MCFeIIIN(shi)-5](OAc)2Cl(C5H5N)6 (Ln1), where OAc– is acetate, shi3− is salicylhydroximate, and Ln = Gd and Dy, were synthesized via a self-assembly reaction in methanol and pyridine. Single crystals were grown using slow evaporation and characterized using X-ray diffraction. Seven-coordinate capped octahedron geometries were observed for the lanthanide ion in both complexes, which is uncommon for trivalent lanthanide species. The 15-MC-5 is a ruffled metallacrown archetype similar to previously reported mixed-valent manganese metallacrowns. The title metallacrown (MC) complexes LnIII[15-MCFeIIIN(shi)-5](OAc)2Cl(C5H5N)6 (Ln1), where OAc– is acetate, shi3− is salicylhydroximate, and Ln = Gd and Dy, contains seven-coordinate capped octahedron geometries for the lanthanide ion in both complexes, which is uncommon for trivalent lanthanide species.