Tetranuclear copper(II) complex of 2-hydroxy-N,N′-bis[1-(2-hydroxyphenyl)ethylidene]propane-1,3-diamine

Abstract

The title molecular structure, namely, (μ3-acetato)(μ2-acetato)bis(μ3-1,3-bis{[1-(2-oxidophenyl)ethylidene]amino}propan-2-olato)tetracopper(II) monohydrate, [Cu4(C19H19N2O3)2(CH3CO2)2]·H2O, corresponds to a non-symmetric tetranuclear copper complex. The complex exhibits one ligand molecule that connects two copper CuII metal centres via its ethanolato oxygen anion acting in a μ2-mode and one ligand molecule that connects three copper CuII metal centres via its ethanolato 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 ethanolate oxygen atom. These two units are connected respectively to the CuO3N unit via one μ3-O ethanolate 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 pentacoordinated CuII 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 intramolecular O—H...O hydrogen bonds is observed. In the crystal, the units are connected by intermolecular C—H...O and O—H...O hydrogen bonds, thus forming sheets parallel to the ac plane