Specific ion/molecule reactions are demonstrated that distinguish the structures of the following isomeric organosilylenium ions: Si(CH3) 3 (+) and SiH(CH3)(C2H5)(+); Si(CH3)2(C2H5)(+) and SiH(C2H5) 2 (+) ; and Si(CH3)2(i-C3H7)(+), Si(CH3)2(n-C3H7)(+), Si(CH3)(C2H5) 2 (+) , and Si(CH3)3(π-C2H4)(+). Both methanol and isotopically labeled ethene yield structure-specific reactions with these ions. Methanol reacts with alkylsilylenium ions by competitive elimination of a corresponding alkane or dehydrogenation and yields a methoxysilylenium ion. Isotopically labeled ethene reacts specifically with alkylsilylenium ions containing a two-carbon or larger alkyl substituent by displacement of the corresponding olefin and yields an ethylsilylenium ion. Methanol reactions were found to be efficient for all systems, whereas isotopically labeled ethene reaction efficiencies were quite variable, with dialkylsilylenium ions reacting rapidly and trialkylsilylenium ions reacting much more slowly. Mechanisms for these reactions and differences in the kinetics are discussed.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.