Oxaziridine synthesis

Preparation of spirooxaziridines from cyclic ketones poses no problems nor does oxaziridine synthesis from cyclic Schiff bases, which was preferably carried out with pyrro-lines to give, for example (245) (59JCS2102) and, in connection with tranquilizer synthesis, with heterocyclic seven-membered rings to give, for example, (246) (63JOC2459). 

Compound (247) is one of the rare examples of an oxaziridine having an orthoacid carbon in the ring (71TL4519). The formation of (248) demonstrates how far oxaziridine synthesis can be extended into the field of unconventional chemicals (80IC1330). 

The addition of oxygen across the C—N double bond is a common and synthetically useful process. The product oxaziridines are of interest for theoretical reasons (largely due to the high configurational stability of the chiral nitrogen), as reagents (such as oxygen transfer moieties), and as synthetic intermediates. The stereochemical aspects of oxaziridine synthesis and reactivity have been reviewed. ... 

Oxaziridines bearing no substituent at nitre en were not, until recently, prepared by the peracid procedure. They became available only after the discovery of a novel oxaziridine synthesis, which instead of formally adding oxygen to a C=N double bond consisted in adding an imino group to a C=0 double bond. The first compound of this type was prepared by Schmitz and Ohme ° in 1961 by treating cyclohexanone with an alkaline solution of hydroxylamine-O-sulfonic acid. S,3-Pentamethyleneoxaziridine (34) was formed (ca. 50% yield) in an extremely fast reaction. Analogous compounds were prepared from methyl ethyl ketone and benzaldehyde (yields ca. 30%). 

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