Anchoring of Copper(II)–Schiff Base Complex in SBA-15 Matrix as Efficient Oxidation and Biomimetic Catalyst

Abstract

A new mononuclear Cu(II) complex [Cu(L2)(H2O)2], where L is the Schiff base 2-[2-(3-bromopropoxy)benzylideneamino] benzoic acid, was synthesized and covalently anchored onto an amino-functionalized SBA-15 mesoporous silica in order to obtain an efficient heterogeneous catalyst. The elemental, structural, textural and morphological characterization confirmed the coordination of the central Cu(II) ion with two ligands and two H2O molecules in the synthesized complex and its successful immobilization into the inner pore surface of the NH2-functionalized support without the loss of the mesoporous structure. The catalytic activity of the free or immobilized Cu(II) complex was tested in the oxidation of cyclohexene with H2O2 under an air atmosphere and the dismutation reaction of the superoxide radical anions with very good results. In addition, catalyst reuse tests claim its suitability in alkene oxidation processes or as a biomimetic catalyst.

Keywords

• catalyst
• SBA-15
• Schiff bases
• Cu(II) complexes
• cyclohexene oxidation
• superoxide dismutase activity