Synthesis and X-ray crystal structures of two novel dinuclear methoxo-bridged hexafluoropentanedionato Er(III) complexes with 1,10-phenanthroline and 2,2′-bipyridine

The reaction of Er(CF3SO3)3 with 1,1,1,5,5,5-hexafluoropentane-2,4-dione (Hhfpd), CsOH·H2O and either 2,2′-bipyridine (bpy) or 1,10-phenanthroline (phen) in methanol yields the new dinuclear complexes [Er(hfpd)2(μ-OCH3)(bpy)]2 (1), and [Er(hfpd)2(μ-OCH3)(phen)]2 (2). The X-ray crystal structures of complexes 1 and 2 show these compounds to consist of two Er(hfpd)2(bpy) and Er(hfpd)2(phen) subunits, respectively, bridged by two methoxo ligands. Each Er3+ ion is octacoordinated with a [ErO6N2] chromophore, with ErO(CH3) distances of 2.23–2.24 Å, ErO(hfpd) bond lengths of 2.32–2.42 Å and ErN distances of 2.51–2.54 Å.