The Characterization of HOC 6 H 4 + and C 6 H 5 O + Ions by Ion—Molecule Reactions

Ion–molecule reactions of some isomeric [C₆,H₅,O]⁺ ions with methanol, acetonitrile, acetone, benzene and toluene were studied in a triple quadrupole mass spectrometer. The C₆H₅O⁺ ion (I) formed adducts with the above molecules, whereas the isomeric HOC₆H₄⁺ (II) ions reacted with methanol to give (HO)₂C₆H₄^+•. This reaction was diagnostic for ions of structure II. Isomers I and II also reacted differently with acetone forming C₆H₅O⁺C₃H₄ and HOC₆H₄O⁺H₂, respectively. No major differences were found in the reactivities of ortho-, meta- and para-hydroxyphenyl ions, although the latter two produced a greater relative abundance of adducts with toluene.