Gas-phase reactions of rhenium-oxo species ReOn+, n = 0, 2–6, 8, with O2, N2O, CO, H2O, H2, CH4 and C2H4

Abstract

The reactions of ReOn+, n = 0, 2–6, 8, with the small molecules O2, N2O, CO, H2O, H2 , CH4 and C2H4, are studied by Fourier transform ion cyclotron resonance (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 methane activation and epoxidation reactions. Re+ reacts with ethylene by sequential dehydrogenation. ReO2+ and ReO4+ exhibit the most diverse reaction pathways, while ReO5+ almost exclusively undergoes ligand exchange. ReO6+ and ReO8+ are largely unreactive, the only efficient reactions observed are with ethylene and water. Both molecules seem to be able to directly attack the dioxygen ligands. The observed chemistry is governed by a fine interplay between available coordination sites and thermochemistry.