Aqua­{2-(pyridin-2-yl)-N-[(pyridin-2-yl)methyl­idene]ethanamine-κ³N,N′,N′′}(sulfato-κ²O,O′)copper(II) tetra­hydrate

The title complex, [Cu(SO₄)(C₁₃H₁₃N₃)(H₂O)]·4H₂O, was obtained by mixing copper sulfate penta­hydrate and 2-(pyridin-2-yl)-N-(pyridin-2-yl­methyl­idene)ethanamine in eth­anol under reflux conditions. The Cu^II ion shows a Jahn–Teller-distorted octa­hedral geometry, with equatorial positions occupied by three N atoms from the tridentate ligand (average Cu—N = 2.004 Å) and one O atom from a bidentate sulfate anion [Cu—O = 1.963 (2) Å]. The axial positions are occupied by one O atom from a coordinating water mol­ecule [Cu—O = 2.230 (3) Å] and one weakly bonded O atom [Cu—O = 2.750 (2) Å] from the bidentate sulfate ion. The complex mol­ecules are connected through O—H...O hydrogen bonds between the coordinating water mol­ecules and sulfate ions from neighboring complexes, forming a double chain parallel to the c axis. The chains are stabilized through additional hydrogen bonds by one of the non-coordinating water mol­ecules bridging between neighboring strands of the double chains. The remaining three water mol­ecules fill the inter­stitial space between the double chains and are involved in an intricate hydrogen-bonding network that consolidates the structure.

Dichlorido{N′-[phen­yl(pyridin-2-yl-κN)methyl­idene]isonicotinohydrazide-κ²N′,O}zinc

The title compound, [ZnCl₂(C₁₈H₁₄N₄O)], crystallizes with two mol­ecules in the asymmetric unit, which differ in the tautomeric (neutral and zwitterionic) forms of the coordin­ating organic ligand. In both mol­ecules, the Zn^II atom adopts a distorted square–pyramidal geometry by two N and one O atoms of the Schiff base ligand and two Cl atoms acting as monodentate chloride anions. The crystal packing is stabilized by N—H...N and N—H...Cl hydrogen bonds, forming a two-dimensional network parallel to the ac plane.