Assembly of anion-controlled cadmium(II) coordination polymers from the use of 2-acetyl-pyridyl-isonicotinoylhydrazone

Crystal structure and Hirshfeld surface analysis of di-iodido-{N'-[(E)-(phen-yl)(pyridin-2-yl-κN)methylidene]pyridine-2-carbohydrazide-κ2 N',O}cadmium(II)

In each of the two independent mol-ecules in the asymmetric unit of the title compound, [CdI2(C18H14N4O)], the N,O,N'-tridentate N'-[(E)-(phen-yl)(pyridin-2-yl-κN)methyl-idene]pyridine-2-carbohydrazide ligand and two iodide anions form an I2N2O penta-coordination sphere, with a distorted square-pyramidal geometry, with an I atom in the apical position. Both mol-ecules feature an intra-molecular N-H⋯N hydrogen bond. In the crystal, weak aromatic π-π stacking inter-actions [centroid-centroid separation = 3.830 (2) Å] link the mol-ecules into dimers.

Modulation of coordination in pincer-type isonicotinohydrazone Schiff base ligands by proton transfer

We report the synthesis and X-ray characterization and theoretical study of two Hg(ii) complexes with pincer-type isonicotinohydrazone Schiff base ligands to analyze chelate-ring π-stacked assemblies.

Crystal structures of di-bromido-{N-[(pyridin-2-yl-κN)methyl-idene]picolinohydrazide-κ2N',O}cadmium methanol monosolvate and di-iodido{N-[(pyridin-2-yl-κN)methyl-idene]picolinohydrazide-κ2N',O}cadmium

The title compounds, [CdBr2(C12H10N4O)]·CH3OH, (I), and [CdI2(C12H10N4O)], (II), are cadmium bromide and cadmium iodide complexes of the ligand (E)-N'-(pyridin-2-yl-methyl-ene)picolinohydrazide. Complex (I) crystallizes as the methanol monosolvate. In both compounds, the Cd2+ cation is ligated by one O atom and two N atoms of the tridentate ligand, and by two bromide anions forming a Br2N2O penta-coordination sphere for (I), and by two iodide anions forming an I2N2O penta-coordination sphere for (II), both with a distorted square-pyramidal geometry. In the crystal of complex (I), mol-ecules are linked by pairs of N-H⋯O and O-H⋯Br hydrogen bonds, involving the solvent mol-ecule, forming dimeric units, which are linked by C-H⋯Br hydrogen bonds forming layers parallel to (101). In the crystal of complex (II), mol-ecules are linked by N-H⋯I hydrogen bonds, forming chains propagating along [010]. In complex (II), measured at room temperature, the two iodide anions are each disordered over two sites; the refined occupancy ratio is 0.75 (2):0.25 (2).