Crystal structure of bis{1-phenyl-3-methyl-4-[(quinolin-3-yl)iminomethyl-κN]-1H-pyrazol-5-olato-κO}zinc methanol 2.5-solvate from synchrotron X-ray diffraction

Abstract

The title compound, [Zn(C20H15N4O)2]·2.5CH3OH, I, was synthesized via the reaction of zinc acetate with the respective ligand and isolated as a methanol solvate, i.e., as I·2.5CH3OH. The crystal structure is triclinic (space group P-1), with two complex molecules ( A and B ) and five methanol solvent molecules in the asymmetric unit. One of the five methanol solvent molecules is disordered over two sets of sites, with an occupancy ratio of 0.75:0.25. Molecules A and B are conformers and distinguished by the conformations of the bidentate 1-phenyl-3-methyl-4-[(quinolin-3-yl)iminomethyl]-1H-pyrazol-5-olate ligands. In both molecules, the zinc cations have distorted tetrahedral coordination spheres, binding the monoanionic ligands through the pyrazololate O and imine N atoms. The two ligands adopt slightly different conformations in terms of the orientation of the terminal phenyl and quinoline substituents with respect to the central pyrazololate moiety. The molecular geometries of A and B are supported by intramolecular C—H...O and C—H...N hydrogen bonds. In the crystal of I, molecules form dimers both by secondary intermolecular Zn...O [3.140 (2)–3.553 (3) Å] and π–π stacking interactions. The dimers are linked by intermolecular hydrogen bonds through the solvent methanol molecules into a three-dimensional network.