Crystal structure of bisμ2-2,2′-[(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

The title compound, [CaCo2(C22H30N4O6)2](ClO4)2 ·1.36H2O or {Ca[Co-(H-2L1)]2} ·2ClO4 ·1.36H2O {where L1 is 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 N4O2 donor 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 CoII cation preorganizes L1 and 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- CaIII-CoIII complexes are connected in three dimensions via weak 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 twocomponent inversion twin [BASF parameter = 0.14 (4)].