Grafting of the η⁵-CpMo(CO)₃ moiety on pure and surface modified SBA-15 molecular sieves

The η⁵-CpMo(CO)₃ moiety is grafted directly or with an aromatic-iodosilane linker on SBA-15 (SBA-15DG and SBA-15ASG) surfaces. The appearance of strong IR bands around 2016 and 1956 cm^-1 on the grafted samples demonstrate the presence of carbonyl groups and evidence the successful grafting of the η⁵-CpMo(CO)₃ moiety. Elemental analyses reveal 1.5 and 4.9 wt.% Mo on the SBA-15DG and SBA-15ASG samples, respectively. The XRD analyses, N₂ adsorption-desorption curves, and TEM analyses provide strong evidence that the mesoporous structures of the supporting materials retain their long range ordering throughout the grafting process, despite significant reductions of the surface areas, pore volumes and pore sizes. The modified materials are found to be active for the catalytic epoxidation of cyclooctene. The catalytic activity of the SBA-15ASG sample remains largely unchanged throughout several recycling experiments.