Characterization of gas phase aggregates of bis(2-ethylhexyl)-sulfosuccinate (AOT) and divalent metal ions: elimination of radical species in the decomposition pathways of even-electron [AOTMIICl2]– anions

Structure and properties of even-electron anionic species formed by bis(2-ethylhexyl)sulfosuccinate (AOT) and divalent metal ions (MII) with stoichiometry [AOTMIICl2] have been investigated by using electrospray ionization and different mass spectrometry techniques, such as high resolution, accurate mass measurements, collision-induced dissociation (CID) multiple-stage mass spectrometry. Owing to CID, eliminations of neutrals, mainly consisting in hydrochloric acid, 2-ethyl-1-hexene and 2-ethylhexanol, and an unexpected loss of an alkyl radical have been observed. The radical anions [C4HO6SMIICl] so produced have been characterized by MS3 experiments. Density functional theory calculations have been carried out for investigating structure and stability of the ionic species formed in the decomposition pathways. Copyright (c) 2012 John Wiley & Sons, Ltd.