The reaction of CH4+, CH3+, and other simple carbocations with benzene in the gas phase

Abstract

The reactions of simple carbocations with neutral benzene molecules have been studied in a triple quadrupole mass spectrometer, which has been described previously. The apparatus can be used to determine quantitatively all the cationic products of these ion-molecule reactions. Four types of reaction have been observed: (i) simple charge exchange, (ii) hydrogen atom transfer, (iii) charge exchange with hydrogen-atom scrambling, and (iv) disproportionation, also with hydrogen atom scrambling. No adduct ions of the type postulated as intermediates (‘Wheland Intermediates’ or ‘σ-complexes’) in Friedel–Crafts alkylation reactions in solution, were observed.