Generation of alkoxide anions from a series of aliphatic diols and alcohols and their ion-molecule reactions with carbon dioxide in the gas phase

Abstract

Alkoxide anions, [M – H^– from a series of aliphatic diols and alcohols are generated in the source under negative ion electrospray ionisation conditions by cone- voltage fragmentation of the corresponding [M + F]^– ions. The collision-induced dissociation (CID) spectra of [M – H]^– ions consist of [M – H2H]– ions, in addition to the other characteristic fragment ions, and the relative abundance of [M – H2H^– ions among the series of diols varies as a function of chain length that could be explained based on their stabilities through intramolecular hydrogen bonding. The reactivity of alkoxide anions is studied through ion–molecule reactions with CO₂ in the collision cell of a triple quadrupole mass spectrometer. All the alkoxide anions reacted with CO₂ and formed corresponding carbonate anions, [M – H + CO₂]^– ions. The reactivity of alkoxide anions within the series of diols also reflected the stability of their [M – H]^– ions