The electron‐impact‐induced fragmentation of aromatic aldoximes: I

Abstract

Primary fragmentations of benzaldoxime include loss of H', OH', HCN, CO and HCNO and this paper discusses the first three losses. The previously reported losses of H 2 0 and 0 were proven to be thermal in origin. Information about the investigated fragmentations was obtained from the deuterated analogues and their metastable characteristics. The OH' elimination is complex. The loss of HCN exhibits a metastable with a composite structure. This fragmentation may occur both via a 4-centred and 5-centred mechanism. A fluorine atom at the ortho position of the phenyl ring favours the 5-centred mechanism.

Studies on coordination compounds vii, chromatographic, thermoanalytical and spectroscopic studies on thermal decomposition of cadmium(II) and lead(II) salicyl-aldoximates

“…5, which differs from that presented for benzaldoxime [16], confirms that the compound in question is not benzaldoxime formed by the same process from salicylaldoxyme.…”

Mass spectrometric behaviour of 4-(arylimino)pentan-2-ones substituted with a halogen atom in the aromatic ring

“…We suggest that the elimination of an acetyl radical is followed by a skeletal rearrangement (Scheme 1) because an HCN molecule is cleaved from the [M 20 43] C ion. The elimination of hydrogen cyanide has been observed earlier for Schiff bases, as a result of a reaction proceeding through a cyclic transition state, 19,20 and also for nitrogen-containing heterocyclic compounds. 21,22 Summing up, we wish to emphasize that several examples of a deviation from the 'even electron rule' were presented.…”

Pentafluorobenzaldehyde and its utilizing in organic synthesis

“…In the literature the preparations of isoxazole derivatives from pentafluorobenzaldehyde oximes [477][478][479] through the pentafluorobenzaldehyde are known.…”