COMPARISON OF THE THERMAL AND MASS-SPECTROMETRIC FRAGMENTATION OF 2,4-THIOXO(OXO)DIHYDRO-5,6-BENZO-1,3-THIAZINES

Article abstract of DOI:10.1007/BF00513256

The pyrolysis of a series of phenyl- and methyl-substituted 2,4-thioxo(oxo)dihydro-5,6-benzo-1,3-thiazines at the Curie point was studied.Processes involving retrodiene fragmentation with the formation of, respectively, phenyisothiocyanate or phenylisocyanate lie at the foundation of the thermal transformations of these compounds.Among other stable pyrolysis products, aniline, benzonitrile, and benzene were identified by gas chromatography and mass spectrometry.Pyrolysis directly in the mass spectrometer gives a larger number of fragmentation products, since it makes it possible to also record compounds with low stabilities.The results of the two methods of analysis correlate well with one another.