Gas-phase reactions of rhenium-oxo species ReOn+, n=0, 2-6, 8, with O-2, N2O, CO, H2O, H-2, CH4 and C2H4

The reactions of ReOn+, n=0, 2-6, 8, with the small molecules O-2, N2O, CO, H2O, H-2, CH4 and C2H4, are studied by Fourier transform ion cyclotron res onance (FT-ICR) mass spectrometry under single collision conditions on the timescale of seconds. The ReOn+ species are produced by laser vaporization of solid rhenium and pulsed supersonic expansion in a helium-oxygen mixture into high vacuum. A wide variety of reactions are observed, including meth ane activation and epoxidation reactions. Re+ reacts with ethylene by seque ntial dehydrogenation. ReO2+ and ReO4+ exhibit the most diverse reaction pa thways, while ReO5+ almost exclusively undergoes ligand exchange. ReO6+ and ReO8+ are largely unreactive, the only efficient reactions observed are wi th ethylene and water. Both molecules seem to be able to directly attack th e dioxygen ligands. The observed chemistry is governed by a fine interplay between available coordination sites and thermochemistry.