A binuclear unsymmetrical compartmental Ni^II complex: [μ-11,24-dimethyl-16,19-dioxa-3,7,15,20-tetra-aza-tricyclo[20.3.1.1 ^9,13]hepta-cosa-1(25),2,7,9,11,13(27),14,20,22(26),23-deca-ene-26, 27-diolato]bis-[diaqua-nickel(II)] bis(per-chlorate) tetra-hydrate

In the title compound, [Ni2(C23H24N4O4)(H2O)4](ClO4)2·4H2O, each NiII atom is coordinated by two bridging phenoxide O atoms, two azomethine N atoms and two water mol-ecules in a slightly distorted octa-hedral geometry. The crystal packing is stabilized by inter-molecular O - H⋯O hydrogen bonds mediated through the water mol-ecules and perchlorate anions. The bis-(amino-oxy)ethane and diamino-propane groups are disordered across the centre of the mol-ecule, and as a result the complex mol-ecule and the crystal structure is centrosymmetric. © International Union of Crystallography 2007.