Isomerization and fragmentation of aliphatic ether radical cations: Interconversion of distonic ions and cyclopropane intermediates

Abstract

AbstractThe reactions of propyl ether radical cations close to threshold are initiated by (reversible) formation of γ‐disitonic isomers, R\documentclass{article}\pagestyle{empty}\begin{document}$ \mathop {\rm O}\limits^ + $\end{document} (H)CH2CH2CH2·. The three methylene groups in these ions lose their positional identity by ring closure/ring opening via [cyclopropane + alcohol]+· intermediates. Extensive hydrogen exchange occurs within the C3‐chain. When R is not methyl the γ‐distonic isomer undergoes further intramolecular hydrogen atom transfer reactions that lead to formation of α‐ and β‐distonic ions. The α‐distonic isomers expel ethyl and propyl radicals by CO bond cleavage.