Intramolecular benzyl cation transfer in the fragmentation of Cinchona alkaloid-based quaternary ammonium cations

摘要: Abstract The fragmentation reactions of Cinchona alkaloid-based quaternary ammonium cations were characterized by collision-induced dissociation mass spectrometry. Besides the common elimination water and formation benzyl cations, title compounds show two distinct resulting from intramolecular cation transfer. In one channel, is transferred initial site (nitrogen) to hydroxyl group leading corresponding alcohol. another precursor ion first dissociates into an intermediate ion–neutral complex consisting neutral partner. intra-complex electrophilic aromatic substitution through attack leads protonated benzylquinoline. Such occurs after migrates a with highest benzylation nucleophilicity different (hydroxylic oxygen or ring carbon), which typical example dissociative