| Autor: |
Partanen, Tuula, Vainiotalo, Pirjo, Stájer, Géza, Bernáth, Gábor, Pihlaja, Kalevi |
| Zdroj: |
Organic Mass Spectrometry; 1990, Vol. 25 Issue 11, p615-619, 5p |
| Abstrakt: |
Mass spectral fragmentations of four norbornane/ene di- exo- and di- endo-fused 1,3-oxazin-2(1 H)-ones and four 1,3-oxazine-2(1 H)-thiones were examined by means of metastable ion analysis, the collision-induced dissociation technique and exact mass measurement. Under electron impact (EI) conditions all the saturated compounds gave rise to complicated fragmentations, including several rearrangements. For the unsaturated compounds, a retro-Diels-Alder (RDA) process was the most favoured fragmentation pathway, which took place with hydrogen rearrangement to yield RDA + H fragments. The EI mass spectra did not permit isomeric differentiation. Under chemical ionization conditions, stereochemical effects were more perceptible, but isomeric differentiation was still difficult. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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