Oxaziranes pyrolysis

Oxaziranes are in a real sense active oxygen compounds and exhibit many reactions grossly analogous to those of organic peroxides. Thus they undergo one electron transfer reaction with ferrous salts and on pyrolysis they are converted to amides. Oxaziranes are also useful synthetic intermediates since in appropriate cases they may be isomerized to aromatic nitrones which are a convenient source of N-alkylhydroxylamines. The reaction of oxaziranes with peracids also provides a source of nitrosoal-kanes and is in many instances the method of choice for preparation of these compounds. ... 

As mentioned above, the oxazirane ring ha limited stability. The products of its thermal decomposition vary considerably with the structure of the oxaoirane and also with the pyrolysis conditions. The products of thermal decomposition of the 3-arytoxaziraoes are the isomeric nitrones. This is apparently a general reaction and may be conveniently accomplished by beating solutions of the oxasiraun in... 

Several examples of oxazirane pyrolysea have been reported.4 19 Typical illustrations of thla phenomenon include the pyrolysis of 2-tert-ootyloxazirane and 2-Mobutyh3,3-pontamethylonooxazirane. The latter example is of some interest in that it involves ring expansion and is the basis of a convenient synthesis of Jf-alkylcaprulactams. In... 

In this sequence a radical, possibly a btradical derived from unpairing the electrons of the oxazirane oxygen-nitrogen bond, abstracts the a-hydrogen atom of the A -alkyl group to form (XXI) which subsequently isomerizes to (XXII). Alternatively the formation of (XXII) may take place directly by a concerted, reaction. In either event the iminoaikoxy radical (XXII) carries the chain. The ammonia which is formed presumably comes from aldol-like condensations of the imine (XXIV). The fact that vapor-phase pyrolysis does not take this course simply reflects tbo low probability of a chain reaction in the vapor phase. 

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