Vanadium Oxo Organometallic Species Supported on Silica for the Selective Non-oxidative Dehydrogenation of Propane

The molecular complex V(═O)(Mes)3 (1) reacts with silica partially dehydroxylated at 700 °C (SiO2-700) to afford (≡SiO)V(═O)(Mes)2 (2) as the major surface species, while a bis-grafted surface species (≡SiO)2V(═O)(Mes) (3) is obtained on SiO2-200. These surface species were characterized by DRIFT, Raman, 1H, 13C, and 51V solid-state NMR, and XAFS spectroscopy and show an activity in the non-oxidative dehydrogenation of propane at 500 °C. The bipodal surface organometallic complex displays a higher selectivity in propylene in comparison to the monopodal species.