A melamine supported on TiO2 coated Fe3O4@C nanocomposite as a bifunctional, effective and reusable catalyst for the Knoevenagel condensation reaction

Abstract

In this study, a novel magnetic melamine-supported on TiO₂ coated Fe₃O₄@carbon nanocomposite with a core–shell structure (Fe₃O₄@C@TiO₂/melamine) as a bifunctional catalyst is successfully synthesized via chemical grafting of propylmelamine groups on an Fe₃O₄@C@TiO₂ nanocomposite. The physicochemical properties of this catalyst were characterized by VSM, EDX, XRD, FT-IR, TGA and SEM techniques. The catalytic activity of Fe₃O₄@C@TiO₂/melamine was studied in the Knoevenagel condensation of ethyl cyanoacetate with various benzaldehydes (electron-donating and electron-withdrawing groups) at 50 °C under solvent-free conditions. This catalyst was recovered and reused several times without significant decrease in efficiency and stability.