Crystal structures and supramolecular architectures of ONO donor hydrazone and solvent exchangeable dioxidomolybdenum(VI) complexes derived from 3,5-diiodosalicyaldehyde-4-methoxybenzoylhydrazone: Hirshfeld surface analysis and interaction energy calculations

Abstract

A tridentate ONO donor aroylhydrazone, 3,5-diiodosalicyaldehyde-4-methoxybenzoylhydrazone (H2DSMB), and two of its cis-MoO2 complexes, [MoO2(DSMB)(H2O)](DMF)2 (1) and [MoO2(DSMB)(py)] (2), have been synthesized and characterized by different physico-chemical methods. The molecular structures were determined by single crystal X-ray diffraction studies. The aroylhydrazone H2DSMB crystallizes in a monoclinic space group with two identical molecules in the asymmetric unit. The complex [MoO2(DSMB)(H2O)](DMF)2 (1) crystallizes in a triclinic space group whereas the other complex, [MoO2(DSMB)(py)] (2), crystallizes in an orthorhombic crystal system. The distorted octahedral geometry around the Mo(VI) central atom is satisfied by the di-deprotonated dianionic hydrazone moiety and two oxido oxygen atoms, the sixth labile coordination site being occupied by oxygen/nitrogen atoms from solvent molecules. The importance of van der Waals interactions in the formation of the elementary structure obtained from the single crystal X-ray diffraction was authenticated by Hirshfeld surface analysis. The individual types of intermolecular contacts and their impact on the crystal packing was investigated by the analysis of the Hirshfeld surfaces and the signatures on the two-dimensional fingerprint plots. Interaction energy calculations reveal that the dispersion energy framework is dominant over other energy frameworks. The thermal behavior and the nature of the water molecule in the complex [MoO2(DSMB)(H2O)](DMF)2 (1) is discussed. Furthermore, in vitro cytotoxicity studies of the synthesized aroylhydrazone and its Mo(VI) complexes against the lymphoma ascites cell line are also included.