Preparation of Mesoporous Silica Nanostructure Functionalized With Hydrobenzoin Substituted Phthalocyanine and Its Catalytic Performance in Benzyl Alcohol Oxidation

Abstract

ABSTRACTIn this study, a new mesoporous silica nanostructure functionalized with hydrobenzoin substituted cobalt (II) phthalocyanine (MCM‐41‐CoPc) was prepared by grafting first 3‐chloropropyltriethoxysilane (CPTES) and then peripherally hydrobenzoin substituted cobalt (II) phthalocyanine (CoPc) onto mesoporous silica nanomaterial (MCM‐41). The structural properties of heterogeneous catalyst MCM‐41‐CoPc were elucidated by FT‐IR, XRD, TEM, EDS, TGA, solid‐state UV–Vis and N2 sorption analyses. The catalytic performance of MCM‐41‐CoPc was investigated in the oxidation of benzyl alcohol to benzaldehyde. To find the best catalytic conditions for aldehyde selectivity, the effect of the different parameters such as temperature, reaction time, oxidant, solvent, amount of the substrate, and oxidant on the catalytic activity of MCM‐41‐CoPc was investigated in detail. The selective oxidation of benzyl alcohol to benzaldehyde in the presence of MCM‐41‐CoPc was achieved with high aldehyde selectivity (98%) and moderate conversion (57%). The reusability of MCM‐41‐CoPc was tested in three consecutive cycle and no catalytic activity loss was observed. Additionally, it has been determined that the product selectivity can be controlled depending on the type of reaction solvent. When ethyl acetate was used as the solvent, 98.5% conversion rate and 96% benzoic acid selectivity were obtained.