Synthesis, crystallographic structure and hirshfeld surface analysis of nickel(II) chelate derived from O,N,S-donor tridentate thiosemicarbazone

Abstract

• A tridentate ONS donor thiosemicarbazone and its nickel complex was synthesized. • The thiosemicarbazone exhibits thioamido form in the solid state whereas in complex it adopts dianionic thiolato form. • The structure of the complex exhibits distorted square planar in geometry. • Hirshfeld surface analysis and the decomposed 2D fingerprint plots provide a visual analysis of various intermolecular interactions present. • The shape index function shows the presence of π..π stacking interactions. New mononuclear complex [NiLβ-pic] has been synthesized by the reaction of Ni(II) acetate with salicylaldehyde 3-azacyclothiosemicarbazone (H 2 L) in the presence heterocyclic base, β-picoline as an auxiliary ligand. The complex has been investigated by elemental analysis, FT-IR, UV-Vis, 1 H NMR and 13 C NMR spectroscopy. These data show that the thiosemicarbazone acts as a dianionic tridentate ligand and coordinated to the metal through azomethine nitrogen, thioiminolate sulfur and phenolate oxygen. The coordination sphere is completed by β-picoline. The magnetic susceptibility measurement indicates that the complex is mononuclear and diamagnetic. The structure of the compound is also confirmed by single crystal X-ray crystallography and was found to be distorted square planar in geometry around Ni(II) metal ion centre in which the angles deviated from ideal 90° with a maximum value of 6.85° occupied by azomethine nitrogen, thiolato sulfur, phenolato oxygen and pyridyl nitrogen atoms. Hirshfeld surface analysis (d norm surfaces and two-dimensional fingerprint plots) for the compound were performed and discussed.