Heterogenization of an organorhenium(VII) oxide on a modified mesoporous molecular sieve

A novel route to heterogenize an organorhenium(vii) oxide, derived from the well examined methyltrioxorhenium(vii) (MTO), on the surface of an iodosilane-modified MCM-41 is applied. The successful grafting of the -CH ₂-ReO₃ moiety on the surface was evidenced by ¹H CP MAS NMR, IR spectroscopy, TG-MS, and elemental analysis. XRD and TEM analyses confirm the retaining of long-range ordering throughout the grafting process. The rhenium loading of the mesoporous material after heterogenization of MTO is found to be 1.25 wt%. Despite containing formally a derivative of the very sensitive benzyltrioxorhenium(vii) the material is stable at room temperature and applicable as a heterogeneous catalyst for aldehyde olefination reactions.