ISSN:
1573-8353
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract A comparison of the mass spectra of N'-phenyl-3-thioureido-1-diazo-alkan-2-ones (I) with the mass spectra of 2-anilino-5,6-dihydro-4H-1,3-thiazin-5-ones (II) and N'-phenyl-3-ureido-1-diazoalkan-2-ones (III) makes it possible to conclude that under the influence of electron impact the molecular ions of the diazo ketones, through the loss of a molecule of nitrogen, undergo only partial cyclization to the corresponding thiazinones (oxazinones in the case of III). In the case of diazo ketones III virtually all of the [M-N2]+ ions undergo fragmentation without cyclization. Under chemical-ionization conditions (with isobutane as the gas-reactant) the principal fragmentation of the protonated ions of I and III entails cleavage of the C-N bonds. Only a small part of these ions lose a molecule of nitrogen, but it is impossible to establish the structures of the resulting [MH-N2]+ ions from the mass-spectrometric data.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00516204