Mass spectral studies of native and mass-labeled perfluorooctanesulfonamides

This work examines the mass spectra of several environmentally relevant amides, perfluorooctanesulfonamide (FOSA), NMeFOSA, NEtFOSA, and NMe(2)FOSA, under electron ionization conditions. A previous mass spectral study of FOSA and NEtFOSA led the authors to propose possible structures for some of the fragment ions and fragmentation pathways that might explain their formation. In the present communication, further fragment ions are identified for these two compounds and alternative fragmentation pathways proposed. Mass spectral analyses of NMeFOSA and NMe(2)FOSA and of mass-labeled NMeFOSA and NEtFOSA reinforce our conclusions about potential fragmentation pathways for these amides and the fragment ions expected. The mass spectral data presented here will help chemists to identify signals found in a gas chromatographic/mass spectrometric (GC/MS) analysis that stem from these perfluoroalkylsulfonamides.