Differentiation among some isomeric di- and trifunctional aromatic amines by plasma desorption mass spectrometry

Isomeric di- and trifunctional aromatic amines are easily differentiated on the basis of their plasma desorption (PD) mass spectra. Six series of aromatic amines were studied in the positive-ion mode. In each series, the differences observed in the PD mass spectra allow each isomer to be characterized. In the formation of molecular ions, these differences proceed from the competition between electron impact ionization and protonation. Several chemoselective or regioselective reactions such as hydrogenation, hydration, dimerization and some fragmentations also allow isomeric aromatic amines to be differentiated.