Crystal structures of two CuII compounds: catena-poly[[chlorido-copper(II)]-μ-N-[eth-oxy(pyridin-2-yl)methyl-idene]-N'-[oxido(pyridin-3-yl)methyl-idene]hydrazine-κ4 N,N',O:N''] and di-μ-chlorido-1:4κ2 Cl:Cl-2:3κ2 Cl:Cl-di-chlorido-2κCl,4κCl-bis[μ3-eth-oxy(pyridin-2-yl)methano-lato-1:2:3κ3 O:N,O:O;1:3:4κ3 O:O:N,O]bis-[μ2-eth-oxy(pyridin-2-yl)methano-lato-1:2κ3 N,O:O;3:4κ3 N,O:O]tetracopper(II)

Crystal structure of poly[hexa-μ-bro-mido-bis{2-[1-(py-ri-din-2-yl)ethyl-idene-amino]ethanol-ato}tetracopper(II)]

The reaction of the Schiff base 2-[1-(pyridin-2-yl)ethyl-idene-amino]-ethanol (HL), which is formed by reaction of 2-amino-ethanol and 2-acetyl-pyridine with CuBr2 in ethanol results in the isolation of the new polymeric complex poly[hexa-μ-bromido-bis-{2-[1-(pyridin-2-yl)ethyl-idene-amino]-ethano-lato}tetra-copper(II)], [Cu4Br6(C9H11N2O)2]n or [Cu4Br6 L 2]n. The asymmetric unit of the crystal structure of the polymeric [Cu4Br6 L 2]n complex is composed by four copper (II) cations, two monodeprotonated mol-ecules of the ligand, and six bromide anions, which act as bridges. The ligand mol-ecules act in a tridentate fashion through their azomethine nitro-gen atoms, their pyridine nitro-gen atoms, and their alcoholate O atoms. The crystal structure shows two types of geometries in the coordination polyhedrons around Cu2+ ions. Two copper cations are situated in a square-based pyramidal environment, while the two other copper cations adopt a tetra-hedral geometry. Bromides anions acting as bridges between two metal ions connect the units, resulting in a tetra-nuclear polymer compound.

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 CuII metal centres via its ethano-lato oxygen anion acting in a μ2-mode and one ligand mol-ecule that connects three copper CuII 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 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 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.

Hexanuclear copper(II) complex of 2-hy-droxy-N,N'-bis-[1-(2-hy-droxy-phen-yl)ethyl-idene]propane-1,3-di-amine incorporating an open-cubane core

The title mol-ecular structure, namely, di-aqua-tris-(μ3-1,3-bis-{[1-(2-oxidophen-yl)ethyl-idene]amino}-propan-2-olato)-μ3-hydroxido-dinitrato-hexa-copper(II) ethanol tris-olvate, [Cu6(C19H19N2O3)3(NO3)2(OH)(H2O)2]·3C2H5OH, corres-ponds to a non-symmetric hexa-nuclear copper complex. The complex exhibits one core in which three CuII metal centres are mutually inter-connected, two by two, via three phenolato oxygen anions acting in a μ2-mode. These three copper cations are inter-connected in a μ3-mode by one hydroxyl group. An open-cube structure is generated in which each of the CuII cations of the three CuO4N units is connected by two μ2-O anions from phenolate groups and one μ3-O atom from a hy-droxy anion. Each of the three penta-coordinated CuII cations situated in the open-cube unit has a distorted NO4 square-pyramidal environment. Each of these three CuII centres is inter-connected with another CuII cation via one enolate O atom in μ2-mode, yielding one CuNO4 unit and two CuNO3 units. The penta-coordinated CuII atom has a distorted square-pyramidal environment while the two tetra-coordinated copper(II) cations are situated in a square-planar environment. A series of intra-molecular O-H⋯O hydrogen bonds are observed. In the crystal, the units are connected two by two by inter-molecular C-H⋯O and O-H⋯O hydrogen bonds, thus forming sheets parallel to the ac plane.