Chapter 6

Fragmentation of Organic Ions and Interpretation of EI Mass Spectra

  • Cleavage of a sigma-bond
  • Writing conventions for molecular ions
  • Alpha-cleavage
  • Stevenson’s rule
  • Double alpha-cleavage
  • Distonic ions
  • Benzylic bond cleavage
  • Rings plus double bonds
  • Allylic bond cleavage
  • Cleavage of non-activated bonds
  • Recognition of the molecular ion peak
  • McLafferty rearrangemen
  • McLafferty rearrangement with double hydrogen transfer
  • Retro-Diels-Alder reaction
  • Elimination of carbon monoxide
  • Thermal degradation versus ion fragmentation
  • Alkene loss from onium ions
  • Ion-neutral complexes
  • Ortho elimination (ortho effect)
  • Heterocyclic compounds
  • Guidelines for the interpretation of mass spectra