Schiff base catalysts for the oxidation of benzyl alcohol to benzaldehyde

Abstract

Catalysts are crucial in promoting sustainability by facilitating chemical transformations under milder conditions, saving energy, and reducing pollution and by-product formation. In this work, we aimed to synthesize and characterize Schiff base complexes of copper, nickel, cobalt in alcohol oxidation, three asymmetric Schiff bases derived from 2,2’-( propenylenedioxy) di benzaldehyde bis(thiosemicarbazone) After that, catalytic activity of Schiff base complexes (Cu(II), Ni(II) and Co(II)) were investigated on the benzyl alcohol oxidation. Ni(II) complex served as an effective catalyst in converting benzyl alcohol to benzaldehyde with 89% conversion in the presence of TBHP oxidant. Moreover, in the catalytic tests performed using TBHP, H2O2 and m-CPBA oxidants, the highest product conversion (95% benzaldehyde conversion) was achieved in the presence of TBHP. In this study, in which the effect of the substrate-catalyst ratio on catalytic activity was investigated, the reaction was completed at the end of 1 hour at 90 °C in DMF solvent using 2.05x10-6 mol catalyst, 1.02x10-3 mol oxidant, and homogeneous catalysis system.