Selected organometallic compounds are nowadays extensively
used
as highly efficient catalysts in organic synthesis. A great variety
of different ligand systems exists, of which phosphine-based ligands
are a significant subgroup. While mass spectrometry, predominantly
electrospray ionization mass spectrometry (ESI-MS), is a standard
analytical technique for the identification of new ligands and their
metal complexes, there is little information on the behavior of phosphine-based
ligands/molecules by electrospray ionization collision-induced dissociation
tandem mass spectrometry (ESI-CID-MS/MS) at low collision energies
(<100 eV) in the literature. Here, we report a study on the identification
of typical product ions occurring in tandem mass spectra of selected
phosphine-based ligand systems by ESI-CID-MS/MS. The influence on
the fragmentation behavior of different backbones (pyridine, benzene,
triazine) as well as different spacer groups (amine, methylamine,
methylene), which are directly linked to the phosphine moiety, is
investigated by tandem mass spectrometry. In addition, possible fragmentation
pathways are elaborated based on the assigned masses in the tandem
mass spectra with high-resolution accurate mass determination. This
knowledge may be particularly useful in the future for the elucidation
of fragmentation pathways for coordination compounds by MS/MS, where
the studied compounds serve as building blocks.