Crystal structure of bis-{μ 2 -2,2'-[(4,10-dimethyl-1,4,7,10-tetra-aza-cyclo-dodecane-1,7-di-yl)bis(meth-yl-ene)]bis-(4-oxo-4 H -pyran-3-olato)}dicobalt-calcium bis-(perchlorate) 1.36-hydrate.

The title compound, [CaCo2 (C22 H30 N4 O6 )2 ](ClO4 )2 ·1.36H2 O or {Ca[Co(H-2 L1 )]2 }·2ClO4 ·1.36H2 O {where L1 is 4,10-bis-[(3-hy-droxy-4-pyron-2-yl)meth-yl]-1,7-dimethyl-1,4,7,10-tetra-aza-cyclo-dodecane}, is a trinuclear complex whose asymmetric unit comprises a quarter of the {Ca[Co(H-2 L1 )]2 }2+ trinuclear complex, half of a perchlorate ion and 0.34-water mol-ecules. In the neutral [Co(H-2 L1 )] moiety, the cobalt ion is hexa-coordinated in a trigonal-prismatic fashion by the surrounding N4 O2 donor set. A Ca2+ cation holds together two neutral [Co(H-2 L1 )] moieties and is octa-coordinated in a distorted trigonal-dodeca-hedral fashion by the surrounding O atoms belonging to the deprotonated oxide and carbonyl groups of two [Co(H-2 L1 )] 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 -CaII -CoII complexes are connected in three dimensions via weak C-H⋯O hydrogen bonds, which are also responsible for the inter-actions with the perchlorate anions and the lattice water mol-ecules. 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)].