[C6H6,C3H7+] AND [C6H7+,C3H6] ION NEUTRAL COMPLEXES INTERMEDIATE IN THE REACTIONS OF PROTONATED PROPYLBENZENES

From the mass-analysed ion kinetic energy spectra of labelled ions, kinetic energy releases and thermodynamic data, it is proved that protonated n-propylbenzene (1) isomerizes into protonated isopropylbenzene (2). It is also shown that the dissociation of the less energetic metastable ions of (2), leading to ]iso-C3H7]+ and [C6H7]+ product ions, is preceded by H exchange. This H exchange involves two interconverting ion-neutral complexes [C6H6,iso-C3H7+) (2-pi) and [C6H7+, C3H6] (2-alpha).