Ion/molecule reactions involving ionized toluene or ionized methyl benzoate and neutral methyl isocyanide

Ion/molecule reactions involving toluene and methyl isocyanide have been performed in a new rf-only hexapole collision cell recently installed in a large-scale tandem mass spectrometer. Among the various ionized products identified, indole derivatives have been characterized by collisional activation and result from the intermediacy of hydrogen-bridged radical cations and covalently bound dimers. Quantum theoretical computations support these experimental findings. A covalently bound dimer is also proposed in the ion/molecule reaction between ionized methyl benzoate and methyl isocyanide; such a dimer is nevertheless not detected due to the large exothermicity of the reaction leading to the ultimate products ascribed to N-methyl benzonitrilium ion, carbon dioxide and a methyl radical.