Methylene radical cation transfer from ionized oxirane to CH3SCH3 and C6H5SCH3 in the gas phase: Formation of sulphur distonic ions and/or insertion in a carbon–sulphur bond

Abstract

AbstractThe α‐distonic sulphur‐containing ion \documentclass{article}\pagestyle{empty}\begin{document}$ {}^ \cdot {\rm CH}_2 \mathop {\rm S}\limits^ + \left({{\rm CH}_3 } \right)_2 $\end{document} has been generated by transfer of CH from ionized oxirane to dimethyl thioether and distinguished from the molecular ion of ethyl methyl thioether by collision induced dissociation (CID) experiments. In particular, the α‐distonic ion expels CH2 to a minor extent following collision, whereas the molecular ion of ethyl methyl thioether does not undergo this reaction. The metastable C3H8S+˙ ions formed by CH transfer to dimethyl thioether and ionization of ethyl methyl thioether decompose by competing losses of CH3R˙, CH4 and C2H4. The elimination of ethene is taken as evidence for isomerization of the α‐distonic ion to the molecular ion of ethyl methyl thioether prior to spontaneous dissociation. Evidence for the formation of stable α‐distonic sulphur‐containing ions by transfer of CH from ionized oxirane to methyl phenyl thioether has not been obtained. The collision‐induced and spontaneous reactions of the ions formed by CH transfer to methyl phenyl thioether indicate that a mixture of the radical cations of CH3C6H4SCH3, C6H5SCH2CH3 and C6H5CH2SCH3 is generated implying that attack on the phenyl group occurs in addition to a formal insertion of a methylene entity in a CS bond.