Hexanuclear copper(II) complex of 2-hydroxy- N , N ′-bis[1-(2-hydroxyphenyl)ethylidene]propane-1,3-diamine incorporating an open-cubane core

The title molecular structure, namely, diaquatris(μ 3 -1,3-bis{[1-(2-oxidophenyl)ethylidene]amino}propan-2-olato)-μ 3 -hydroxido-dinitratohexacopper(II) ethanol trisolvate, [Cu 6 (C 19 H 19 N 2 O 3 ) 3 (NO 3 ) 2 (OH)(H 2 O) 2 ]·3C 2 H 5 OH, corresponds to a non-symmetric hexanuclear copper complex. The complex exhibits one core in which three Cu II metal centres are mutually interconnected, two by two, via three phenolato oxygen anions acting in a μ 2 -mode. These three copper cations are interconnected in a μ 3 -mode by one hydroxyl group. An open-cube structure is generated in which each of the Cu II cations of the three CuO 4 N units is connected by two μ 2 -O anions from phenolate groups and one μ 3 -O atom from a hydroxy anion. Each of the three pentacoordinated Cu II cations situated in the open-cube unit has a distorted NO 4 square-pyramidal environment. Each of these three Cu II centres is interconnected with another Cu II cation via one enolate O atom in μ 2 -mode, yielding one CuNO 4 unit and two CuNO 3 units. The pentacoordinated Cu II atom has a distorted square-pyramidal environment while the two tetracoordinated copper(II) cations are situated in a square-planar environment. A series of intramolecular O—H...O hydrogen bonds are observed. In the crystal, the units are connected two by two by intermolecular C—H...O and O—H...O hydrogen bonds, thus forming sheets parallel to the ac plane.