The bimolecular reactivity of organosilane radical cations (RSiMe3.+) toward selected bases/nucleophiles (N) has been studied in the gas phase by the FT-ICR technique. The two major reaction pathways are H+ and Me3Si+ transfer, whose branching ratio depends on the features of R and N. The onset for Me3Si+ transfer is close to its thermochemical threshold. Deprotonation of ionized benzyltrimethylsilane is unprecedented in solution but is highly efficient in the gas phase when a strong nitrogen base is used, suggesting a potentially useful route to obtain silylated radicals. The kinetic study of a model degenerate reaction suggests that the activation barrier for Me3Si+ transfer between oxygen centers is negligible, as observed for the corresponding proton-transfer process.
Gas phase reactivity of organosilane radical cations. A FT-ICR study / Chiavarino, Barbara; Crestoni, Maria Elisa; Fornarini, Simonetta. - In: ORGANOMETALLICS. - ISSN 0276-7333. - STAMPA. - 19:(2000), pp. 844-848. [10.1021/om990428a]