Synthesis of a new Zn(II) benzoate complex: crystal structure, Hirshfeld surface analysis, QTAIM/NBO/RDG analyses, DFT and molecular docking studies

A new tetracoordinated zinc(II) complex, formulated as [Zn(2-EtIm)2(CBA)2] (1), where 2-EtIm is 2-ethylimidazole and CBA is 2-chlorobenzoate, has been synthesized and characterized. The crystals of complex 1 were obtained via slow evaporation at room temperature. This complex was characterized by single-crystal X-ray diffraction, FTIR, UV-Vis,1H NMR, and 13C NMR spectroscopy. Complex 1 crystallizes in the monoclinic system with space group P21/n. Hirshfeld surface analysis shows different intermolecular interactions in the crystal. Quantum Theory of Atoms in Molecules (QTAIM), Reduced Density Gradient (RDG), and Natural Bond Orbital (NBO) analyses were employed to investigate the diverse non-covalent interactions stabilizing the crystal structures. The crystal structure is primarily stabilized by weak hydrogen bonds and CH···π interactions. While halogen interactions play a secondary role, some intramolecular C-H···Cl contacts are observed. Notably, unconventional interactions were identified and characterized, including a tetrel CH···Cl interaction and σ(CH)···π* in a dimer.