Investigations of oxonium ions

Abstract

Isotopically labelled methanol was used in an investigation of the ion–molecule reactions of methanol in the gas phase using a triple quadrupole mass spectrometer. A quinqua quadrupole mass spectrometer was used to investigate the formation of trimethyl oxonium ions. The results were used to examine the validity of the alternative mechanisms for the reaction (1) that have been CH₃OH₂⁺+ CH₃OH →(CH₃)₂OH⁺+ H₂O (1) proposed in the literature. The results provide unequivocal support for the S_N2 mechanism.