Tungsten-based organic mesoporous SBA-15 materials: characterization and catalytic properties in the oxidation of cyclopentene to glutaric acid with H2O2

A series of hybrid heterogeneous catalysts were prepared and their catalytic performance was investigated for the first time in the green oxidation of cyclopentene to glutaric acid (GAC) using 50 wt% H2O2. After tungsten active sites embedded into the mesochannels of SBA-15, partial Si-OH groups from the mesoporous surface are removed by further silylation with diphenyldichlorosilane (DPHS). It can provide a more hydrophobic environment in the mesochannels where the tungsten active sites are immobilized, which in turn generates at least two distinct significant characteristics. First, the aperture entrance size of the catalysts finely modulated by grafting DPHS moieties displays lower tungsten species leaching than those of not possessing organic groups. Moreover, the present catalysis system also provides an unprecedented yield of GAC depending on more hydrophobic nature of the catalysis. In addition, the catalyst W-SBA-15-1.6DPHS was recycled and reused in four successive reaction runs without major loss of reactivity.