TuP-15

TuP-15

SEQUENTIAL ION/MOLECULE REACTIONS IN TRIPLE AND QUINQUA QUADRUPOLE MASS SPECTROMETERS

G. STEWART WALKER

Cooperative Research Centre for the Ecologically Sustainable Development of the Great Barrier Reef, James Cook University of North Queensland, Townsville, Queensland 4811 and Australian Institute of Marine Science, Cape Cleveland, PMB No.3, Townsville M.C., Queensland 4810

MSⁿ techniques can be used either to fragment ions or to construct new ions from the reaction of ions and molecules. Such sequential ion/molecule reactions have been studied using a triple quadrupole mass spectrometer and a quinqua quadrupole mass spectrometer.

Examples to be presented include 'ring expansion' reactions (1) involving the 'insertion' of an extra carbon into a carbon (or heterocyclic) ring,

(1) CH₂X⁺ + C₆H₆ -> C₇H₇⁺ (tropylium ion) + HX

formation of protonated hydrocarbons (2) with subsequent rearrangement and fragmentation

(2) M-H⁺ + R --> [M-H-R]⁺ -> M + R-H⁺

and formation of oxonium ions (3) and analogues.

Reaction 3

The use of gaseous ion reactions in a mass spectrometer to model reactions occurring in processes such as catalytic cracking of hydrocarbons and Mobil's methanol to gasoline reaction will be discussed.