Generation, characterization, and properties of iron-silylene and iron-silene cationic complexes in the gas phase

Article abstract of DOI:10.1021/ja00076a046

Generation, characterization, and properties of iron-silylene (Fe=SiRR′) and iron-silene (Fe(CH₂=SiRR′)) cations (R, R′ = H, CH₃) are describe in the gas phase by using Fourier transform mass spectrometry (FTMS). Iron-(silylene/silene) cations were formed by reaction of Fe⁺ with appropriate silanes. Structures of these ions were probed by using both collision-activated dissociation (CAD) and ion/molecule reactions. CAD failed to yield structural information; however, reaction with isotopically labeled ethene provides compelling evidence for formation of iron-silene and iron-silylene species. There is no evidence for the interconversion of iron-silylene and iron-silene species, even upon slow collisional activation or by formation of ethene collision complexes (ca. 40 kcal/mol of excess energy). This indicates that there is a prohibitive barrier for iron mediated interconversion of silene and silylenes. Reactions of iron-silylene and iron-silene species with water and benzene are described. The nature of the bonding is presented and bond dissociation limits are obtained.