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.