Synthesis and Structural Studies of Mn(II) and Zn(II) Thiazole–Schiff Base Complexes with Catalytic Application in Benzyl Alcohol Oxidation

Structural studies and catalytic applications of novel Mn(II) and Zn(II) metal complexes

Abstract

Manganese(II) and zinc(II) Schiff base complexes derived from salicylaldehyde and ethyl 2-(2-amino-1,3-thiazol-4-yl)acetate were synthesized and characterized using elemental analyses, IR and UV–Vis spectroscopy. Their catalytic activities were assessed for the selective oxidation of benzyl alcohol employing hydrogen peroxide as a green oxidant under mild conditions. The gas chromatographic study identified benzaldehyde as the primary product, while benzoic acid and benzyl benzoate as minor by-products. The manganese complex exhibited the superior catalytic activity, (approximately 95% selectivity) due to its redox versatility and enhanced electron-transfer capability. The study demonstrated that optimization of parameters such as reaction time, temperature, H₂O₂ concentration, catalyst loading, and catalyst type significantly influenced both selectivity and conversion. With a selectivity of approximately 95%, this reaction is particularly promising for industrial applications in benzyl alcohol oxidation using environmentally benign catalysts.