Inclusion of organic pyridin-3-onate anions by sheets of hydroxo-bridged Cu(II) dimeric complexes

Abstract

A pillared layered compound [Cu 2(μ-OH) 2(phen) 2(H 2O) 2][Cu 2(μ-OH) 2(HCO 3) 2(phen) 2](3-pyO) 2·10H 2O ( 1) [phen=1,10-phenanthroline, 3-pyOH=3-hydroxypyridine] has been prepared and characterized by X-ray diffraction analysis, thermoanalytical techniques and variable-temperature susceptibility measurements. The compound crystallizes in the triclinic group P 1 ̄ with cell parameters: a=11.499(2), b=11.600(2), c=13.374(3) Å, α=71.88(2)°, β=78.25(2)°, γ=71.36(2)°. Two different centrosymmetric dimers coexist in the crystal structure, one of them is neutral and the other one is a cation. In both dimeric entities the Cu(II) atoms show distorted square-pyramidal environments with the basal plane formed by the two nitrogen atoms of the phenantroline ligand and the oxygen atoms of two bridging hydroxyl groups. The apical positions are filled by the oxygen atom from a water molecule (cationic dimer) or from a monodentate hydrogencarbonato ligand (neutral dimer). The dimers interact by means of hydrogen bonds and offset face-to-face aromatic interactions to form cationic layers. The pyridin-3-onate anions and the crystallization water molecules occupy the space between the layers and cross-link the nearest-neighbour layer by means of hydrogen bonds to afford a three-dimensional structure. Variable temperature measurements show a ferromagnetic intradimer interaction with a J value of +125.5 cm −1.