Electrospray ionization mass spectral fragmentation study of amino acid derived oxovanadium Schiff base complexes and (oxo)-peroxovanadium Schiff base complexes

Amino acid derived oxovanadium Schiff base complexes and their in situ (oxo)-peroxovanadium Schiff base complexes were first studied with electrospray ionization tandem mass spectrometry (ESI-MSn) with collision-induced dissociation (CID). Their fragmentation pathways are proposed on the base of the MSn studies.All of the molecular ions of the two group vanadium complexes easily lose a CO2 molecule under ESI-MS condition. In the dissociation, H2O, VO2 will possibly be eliminated for oxovanadium Schiff base complexes, while (oxo)-peroxovanadium Schiff base complexes always yield the same ion at m/z 314 due to elimination of a molecule of aldehyde from amino acid residues. The dissociation rules may be extended to other metal Schiff base complexes and other peroxo-metal complexes.