Crystal structure of bis{μ2-2,2′-[(4,10-dimethyl-1,4,7,10-tetraazacyclododecane-1,7-diyl)bis(methylene)]bis(4-oxo-4H-pyran-3-olato)}dicobaltcalcium bis(perchlorate) 1.36-hydrate

Abstract

The title compound, [CaCo2(C22H30N4O6)2](ClO4)2·1.36H2O or {Ca[Co(H–2L1)]2}·2ClO4·1.36H2O {whereL1is 4,10-bis[(3-hydroxy-4-pyron-2-yl)methyl]-1,7-dimethyl-1,4,7,10-tetraazacyclododecane}, is a trinuclear complex whose asymmetric unit comprises a quarter of the {Ca[Co(H–2L1)]2}2+trinuclear complex, half of a perchlorate ion and 0.34-water molecules. In the neutral [Co(H–2L1)] moiety, the cobalt ion is hexacoordinated in a trigonal–prismatic fashion by the surrounding N4O2donor set. A Ca2+cation holds together two neutral [Co(H–2L1)] moieties and is octacoordinated in a distorted trigonal–dodecahedral fashion by the surrounding O atoms belonging to the deprotonated oxide and carbonyl groups of two [Co(H–2L1)] units. The coordination of the CoIIcation preorganizesL1and an electron-rich area forms, which is able to host hard metal ions. The comparison between the present structure and the previously published ones suggests a high versatility of this ligand; indeed, hard metal ions with different nature and dimensions lead to complexes having different stoichiometry (mono- and dinuclear monomers and trinuclear dimers) or even a polymeric structure. The heterotrinuclear CoII–CaII–CoIIcomplexes are connected in three dimensionsviaweak C—H...O hydrogen bonds, which are also responsible for the interactions with the perchlorate anions and the lattice water molecules. The perchlorate anion is disordered about a twofold rotation axis and was refined giving the two positions a fixed occupancy factor of 0.5. The crystal studied was refined as a two-component inversion twin [BASF parameter = 0.14 (4)].