Gas-Phase Ion/Molecule Isotope-Exchange Reactions: Methodology for Counting Hydrogen Atoms in Specific Organic Structural Environments by Chemical Ionization Mass Spectrometry

Article abstract of DOI:10.1021/ja00543a009

Ion/molecule reactions are described which facilitate exchange of hydrogens for deuteriums in a variety of different chemical environments.Aromatic hydrogens in alkylbenzenes, oxygenated benzenes, m-toluidine, m-phenylenediamine, thiophene, and several polycyclic aromatic hydrocarbons and metallocenes are exchanged under positive ion CI conditions by using either D2O, EtOD, or ND3 as the reagent gas.Aromatic hydrogens, benzylic hydrogens, and hydrogens on carbon adjacent to carbonyl groups suffer exchange under negative ion CI conditions in ND3, D2O, and EtOD, respectively.A possible mechanism for the exchange process is discussed.