Chelation and Coating Functionalization Influence on the Catalytic Effectiveness of Copper(II) Pyridyl-Schiff Base...

Pyridyl-Schiff base copper(II) chelating compound (CuLscpyCl) with facile preparation and cost-effectiveness was designed. The structure characteristics of the chelating compound (CuLscpyCl) and the corresponding organic ligand HLscpy were determined using alternative spectroscopic tools. The heterogeneous structure of copper(II) chelating compound was achieved through a coating process of TiO₂/Fe₃O₄, giving a novel nano-structural CuLscpyCl@TiO₂/Fe₃O₄. The internal structure, surface morphologies, and elemental components of the nano-composited CuLscpyCl@TiO₂/Fe₃O₄ were studied using many microscopic and spectroscopic methods. Referring to the weakness and strength of the CuLscpyCl chelating compound as an effective catalyst in various oxygenated systems, the catalytic potential of the homogeneous and heterogeneous phases of the Cu-catalyst was investigated for optimizing the oxygenated productivity of 1,2-cyclohexene, benzyl alcohol, and thiophene, utilizing H₂O₂. The reactivity of CuLscpyCl (homogeneously) was estimated with a reduced time for the optimized mono-oxide productivity of 92% cyclohexane-1,2-oxide, 87% benzaldehyde, and 62% thiophene oxide (sulfoxide), respectively. The heterogenized catalyst (CuLscpyCl@TiO₂/Fe₃O₄) documented productivity with a slightly longer duration, but better percentages of 93% cyclohexane-1,2-oxide, 91% benzaldehyde, and 68% thiophene oxide (sulfoxide), respectively. For the recycling, the heterogeneous CuLscpyCl@TiO₂/Fe₃O₄ catalyst was successful within seven trials compared to just two attempts for CuLscpyCl (the homogeneous catalyst) in the oxygenation system of 1,2-cyclohexene.