metal-organic compounds
Open access
The crystal structure of the title compound, [Cu(H2O)6](BF4)2·3C4H4N2O2, comprises discrete [Cu(H2O)6]2+ cations and BF4− anions along with three equivalents of pyrazine 1,4-dioxide (pzdo). The hexaaquacopper(II) ion and all three pzdo molecules lie about crystallographic inversion centers. The lattice is supported by an extensive hydrogen-bonding network. O—HO hydrogen bonding between the [Cu(H2O)6]2+ and pzdo units creates a pseudo-hexagonal lattice parallel to the bc plane. The BF4− anions lie in the voids of that lattice, held in place by O—HF hydrogen bonds, and also generate BF4−–pzdo–BF4−–pzdo stacks via short FN contacts [2.866 (3)–3.283 (4) Å].
metal-organic compounds
Open access
The title compound, [Cu(C12H8N3O2)(N3)(H2O)], was formed by the air oxidation of 2-(aminomethyl)pyridine in 95% ethanol in the presence of copper(II) nitrate and sodium azide with condensation of the resulting picolinamide molecules to generate the imide moiety. The CuII ion has a square-pyramidal coordination sphere, the basal plane being occupied by four N atoms [two pyridine (py) N atoms, the imide N atom and an azide N atom] in a nearly planar array [mean deviation = 0.048 (6) Å] with the CuII ion displaced slightly from the plane [0.167 (5) Å] toward the fifth ligand. The apical position is occupied by a coordinating water molecule [Cu—O = 2.319 (4) Å]. The crystal structure is stabilized by hydrogen-bonding interactions between the water molecules and carbonyl O atoms. The inversion-related square-pyramidal complex molecules pack base-to-base with long CuNpy contact distances of 3.537 (9) Å, preventing coordination of a sixth ligand.