Electron impact mass spectrometry and collisional spectroscopy in the structural characterization of 4-benzylidene and 4-phenylethylidene-2-phenyl-5(4H)-oxazolones

The mass spectrometric behaviour of four isomeric oxazolones is rationalized by means of metastable ion studies and bond order calculations via semiempirical methods. The data allow the identification of a possible intermediate structure of molecular species that accounts easily for the observed primary decomposition pathways.

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