Hydrazone-based dioxidomolybdenum(VI) complexes: catalytic oxidation of omeprazole sulfide.

Four hydrazone-based molybdenum(VI) complexes, namely MoO2(L1)·H2O 1, MoO2(L2)·H2O 2, MoO2(L3)·H2O 3, MoO2(L4)·H2O 4, were successfully synthesized utilizing hydrazone ligands H2L1-H2L4. The structural and physicochemical properties of these ligands and their corresponding molybdenum complexes were elucidated through a comprehensive array of spectroscopic and analytical techniques. Single-crystal X-ray diffraction analysis (SC-XRD) unambiguously confirmed that all four complexes adopt a distorted octahedral arrangement around the metal center. Additionally, powder X-ray diffraction (P-XRD) studies verified the bulk purity of the synthesized complexes. The catalytic potential of all complexes was evaluated in the oxidation of omeprazole sulfide using green oxidant i.e. hydrogen peroxide (H2O2) as an oxidant under both dark and illuminated conditions. Remarkably, all complexes exhibited excellent catalytic efficiency, achieving complete conversion of the omeprazole sulfide substrate with 100% product selectivity.