Formation of proton-bound dimers as the driving force for alkyl radical loss in the gas phase reactions of radical cations

A variety of reactions take place when ethanol, diethyl ether, and ethylamine radical cations react with basic, neutral molecules: isomerization within the encounter complex of the radical cation to its alpha-distonic isomer, proton transfer to the neutral, and loss of an alkyl radical. The initial step is formation, directly when possible or via isomerization, of a proton-bound adduct. This adduct can act as a proton donor or dissociate by loss of an alkyl radical, giving rise to a second proton-bound adduct. The course of these reactions is determined by the exceptional stability of the adducts.