Preparation of Tripodal Vanadium Oxo-Organometallic Species Supported on Silica, [(≡SiO)₃V(═O)], for Selective Nonoxidative Dehydrogenation of Propane

In this work, a strategy based on the grafting of vanadium molecular complex, [V(═O)(OtBu)3], (1), bearing tert-butoxide ligands, partially dehydroxylated silica, followed by thermal treatment has been used for preparation supported tripodal V oxo [(≡SiO)3V(═O)], active species, important chemical processes. The complex reacts with silica at 200 °C (SiO2–200) to lead bipodal [(≡SiO)2V(═O)(OtBu)] (2) as major surface while monopodal species [(≡SiO)V(═O)(OtBu)2] (3) are obtained SiO2–700. These materials were thermally treated form releasing isobutene via β-H transfer, leading V–OH intermediate. latter targeted [(≡SiO)3V(═O)] after restructuration support and will be represented (2a) (3a). All complexes characterized diffuse reflectance infrared Fourier transform (DRIFT), UV–vis, solid-state NMR, X-ray absorption near edge structure (XANES) spectroscopies. particular, isolated was confirmed 51V NMR peak −670 ppm, reported in literature. catalytic property (3a) evaluated direct propane dehydrogenation showed promising performances that can solely assigned species.