Synthesis, crystal structure and Hirshfeld analysis of the bis{(<em>E</em>)-2-[1-(benzo[<em>d</em>][1,3]dioxol-5-yl)ethylidene]-<em>N</em>-ethylhydrazine-1-carbothioamide-κ<em>S</em>}-dichloridomercury(II) complex

Abstract

The title compound, [HgCl₂(C₁₂H₁₅N₃O₂S)2], was synthesized by the reaction of (<em>E</em>)-2-[1-(benzo[<em>d</em>][1,3]dioxol-5-yl)ethylidene]-<em>N</em>-ethylhydrazine-1-carbothioamide [common name: 3′,4′-(methylenedioxy)acetophenone 4-ethylthiosemicarbazone] with mercury(II) chloride in a 2:1 molar ratio at ambient temperature, using ethanol as solvent. A white solid was isolated and colourless single crystals of the title compound for the SC-XRD analysis were obtained from a solution in (methanesulfinyl)methane (common name: dimethyl sulfoxide, DMSO) with a hexane overlay. The Hg^II metal center is fourfold coordinated in a distorted tetrahedral geometry by two neutral thiosemicarbazone derivatives, acting as κ<em>S</em>-donors, and two chlorido ligands. The complex molecule exhibits a sequence of four intramolecular hydrogen-bonded rings, formed by two interactions of the N—H&sdot;&sdot;&sdot;Cl type, with graph-set motifs of <em>S</em>(6) and showing a chelate-like coordination environment around the metal center, and two additional interactions of the N—H&sdot;&sdot;&sdot;N type with <em>S</em>(5) graph-set motifs. In the crystal, the molecules are linked <em>via</em> N—H&sdot;&sdot;&sdot;Cl intermolecular interactions along the <em>c</em>-axis, forming a hydrogen-bonded ribbon-like supramolecular arrangement that resembles a zigzag pattern along the <em>c</em>-axis direction, and with the Cl atoms acting as bridges between intra- and intermolecular hydrogen bonds. The Hirshfeld surface analysis suggests that the major contributions for the crystal cohesion are the H&sdot;&sdot;&sdot;H (40.4%), H&sdot;&sdot;&sdot;Cl/Cl&sdot;&sdot;&sdot;H (14.5%), H&sdot;&sdot;&sdot;C/C&sdot;&sdot;&sdot;H (11.3%), H&sdot;&sdot;&sdot;O/O&sdot;&sdot;&sdot;H (10.6%) and H&sdot;&sdot;&sdot;S/S&sdot;&sdot;&sdot;H (9.2%) intermolecular contacts, with the surface being mapped over the <em>d</em>_norm, shape-index and curvedness properties.