Reactions of copper pyridonate complexes with hydrated lanthanoid nitrates

Abstract

Twenty new copper–lanthanoid complexes have been prepared. The route involves reaction of preformed copper pyridonate complexes with hydrated lanthanoid nitrates in a variety of solvents. Structural characterisation of eleven of these complexes gave some indications of how the structure is controlled in these compounds. Reaction of [Cu ₆ Na(mhp) ₁₂ ][NO ₃ ] (mhp = 6-methyl-2-pyridonate) with hydrated lanthanum nitrate in CH ₂ Cl ₂ leads to a high-nuclearity complex containing a Cu ₁₂ La ₈ core. The twelve Cu atoms are arranged in a cuboctahedron surrounded by a cube of eight La atoms. Similar reactions involving 6-chloro-, 6-bromo- and 6-fluoro-2-pyridonate led to tetranuclear complexes which fall into three distinct structural groups. Consideration is given to the factors governing the choice of structural group.