Experimental and theoretical studies of new dioxomolybdenum complex: Synthesis, characterization and application as an efficient homogeneous catalyst for the selective sulfoxidation

Abstract A new dioxomolybdenum(VI) complex with tridentate ONO-donor Schiff base ligand derived from isoniazid has been synthesized and characterized by elemental analyses, FT-IR and 1H NMR, and its solid state structure was confirmed by single crystal X-ray diffraction (SC-XRD) technique. In the complex, the molybdenum center adopts a slightly distorted octahedral geometry, by using three O,N,O-donor atoms of the tridentate ligand, an oxo group makes the equatorial plane, while a methanol and another oxo group employ the axial positions. QTAIM, MEP, NCI calculations and Hirshfeld surface analysis were performed to investigate the nature and types of non-covalent linkages present among the sample molecules. The theoretical calculations, performed by DFT using the B3LYP/Def2-TZVP level of theory, direct that the intended outcomes are in compliance with the actual consequences. In addition, the catalytic performance of the complex was studied in oxidizing the different sulfides with H2O2 as an oxidizing agent in ethanol as a solvent under refluxed conditions. The main edge of the present catalytic work is the accomplishment of reaction in a short period of time, high percentage yield and full selectivity to sulfoxides without any formation of sulfones.