Design of bifunctionalized hexagonal mesoporous silicas for selective oxidation of cyclohexane

Bifunctionalized hexagonal mesoporous silicas, CoPh-HMS, were designed and successfully synthesized by a one-step co-condensation route at ambient temperature. This new material possesses the typical wormhole structure of HMS material. Co 2+ ions were incorporated into the frameworks in tetrahedral coordination along with phenyl groups immobilized on the surface, confirmed by a careful spectroscopic (Fourier transform infrared, ultraviolet–visible and 29 Si magic-angle spinning nuclear magnetic resonance) study. It was used in the liquid-phase selective oxidation of cyclohexane with molecular oxygen under solvent-free conditions, and showed excellent performance. The results indicate the potential for intentional design of the catalytic environment at a nanometre level with the combination of transition metal incorporation and surface organofunctionalization for mesoporous siliceous materials.