Tetra-nuclear copper(II) complex of 2-hydroxy-N,N'-bis-[1-(2-hy-droxy-phen-yl)ethyl-idene]-propane-1,3-di-amine

The title mol-ecular structure, namely, (μ₃-acetato)(μ₂-acetato)-bis-(μ₃-1,3-bis-{[1-(2-oxidophen-yl)ethyl-idene]amino}-propan-2-olato)tetra-copper(II) monohydrate, [Cu₄(C₁₉H₁₉N₂O₃)₂(CH₃CO₂)₂]·H₂O, corresponds to a non-symmetric tetra-nuclear copper complex. The complex exhibits one ligand mol-ecule that connects two copper Cu^II metal centres via its ethano-lato oxygen anion acting in a μ₂-mode and one ligand mol-ecule that connects three copper Cu^II metal centres via its ethano-lato oxygen anion acting in a μ₃-mode. One bridging acetate group acting in an η¹:η¹-μ₂-mode connects two copper(II) ions while another bridging acetate group connects three copper(II) ions in an η¹:-η²-μ₃-mode. A chair-like Cu₃O₃ structure is generated in which the two CuO₄N units are connected by one μ₂-O ethano-late oxygen atom. These two units are connected respectively to the CuO₃N unit via one μ₃-O ethano-late oxygen atom and one μ₂-O atom from an acetate group. The μ₃-O atom also connects one of the CuO₄N units and the CuO₃N unit to another CuO₃N unit, which is out of the chair-like structure. Each of the two penta-coordinated Cu^II cations has a distorted NO₄ square-pyramidal environment. The geometry of each of the two CuNO₃ units is best described as a slightly square-planar environment. A series of intra-molecular O-H⋯O hydrogen bonds is observed. In the crystal, the units are connected by inter-molecular C-H⋯O and O-H⋯O hydrogen bonds, thus forming sheets parallel to the ac plane.