| Abstract: | The decomposition after electron impact of some N-alkyl and N-aryl pyrrolidin-3-ones has been examined and fragmentation mechanisms influenced by the substituents on the nitrogen have been observed. Accurate mass measurement, deuterium labelling, kinetic energy release measurements and metastable (DADI) ion abundances, permit the elucidation of the probable mechanism of formation of the most intense fragment ions. The available experimental evidence indicates the occurrence of rearrangement processes leading to important product ions in the mass spectra of the N-aryl derivatives. This type of fragmentation has been interpreted as the result of the combined action of two groups on the nitrogen atom of the heterocyclic nucleus. |
