The influence of structural features on facile McLafferty-type, even-electron rearrangements in tandem mass spectra of carboxylate anions

Rapid Commun Mass Spectrom. 2006;20(10):1511-6. doi: 10.1002/rcm.2506.

Abstract

In contrast to the well-described McLafferty rearrangement in odd-electron cations, relatively little has been reported on comparable rearrangements in even-electron ions, especially negative ions. This work reports a systematic study using tandem mass spectrometry (MS/MS) fragment ion spectra of carboxylate anions having a suitably acidic proton in the gamma position. The rearrangement process was studied in both ion trap and triple quadrupole mass spectrometers; characteristic enolate anions and stable neutral products were formed at low collision energies. The process has diagnostic and analytical potential in, for example, the analysis of peptides having C-terminal serine residues and of 3-hydroxy- or 3-aminocarboxylic acids in complex mixtures.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acrylates / chemistry
  • Carboxylic Acids / chemistry*
  • Deuterium / chemistry
  • Electrons
  • Isotope Labeling
  • Protons
  • Spectrometry, Mass, Electrospray Ionization
  • Tandem Mass Spectrometry

Substances

  • Acrylates
  • Carboxylic Acids
  • Protons
  • Deuterium