C chemical shifts for several series of cis-and truns-iV-alkylimines and oxaziridines bearing parasubstituted C-phenyl rings are reported and correlated with dual substituent parameters. The 13C=N and oxaziridine ring carbon shifts correlate primarily with the inductive/field parameters, ul, whereas both resonance and inductive terms generally contribute about equally to the long-range substituent effects on -1 side-chain chemical shifts. Correlations on diastereoisomeric imines show that the transmission of substituent effects can be significantly affected by the E Z configuration. Aromatic carbon chemical shifts in imines are discussed in relation to the E Z configuration and the conformation around the aryl-imino bond. 13

The oxidation of N-alkyl imines by m-chloroperoxybenzoic acid to yield nitrones was facilitated by (i) the presence of C-aryl substituents, (ii) steric inhibition of attack at the imino C-atom, (iii) electron donating para-substituents on the C-aryl substituent, (iv) non-hydroxylic solvents, (v) optimal conjugation between C-aryl substituents and the imino group, and (vi) less bulky N-alkyl groups.The oxidation of N-alkyl imines by dimethyldioxirane (DIM D) in dichloromethane-acetone solution yielded nitrones without evidence of oxaziridine formation. The yields of isolated nitrones were higher for C,C-diary1 imines and for imines bearing less bulky N-alkyl substituents. N-H substituted ketimines were found to yield oximes after reaction with dimethyldioxirane.

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A range of oxaziridines containing N-methylene substituents has been synthesized by peracid oxidation of the corresponding fluorenylidene N-alkylamines. Spontaneous and tertiary amine base-catalysed decomposition of the oxaziridines into unstable N H aldimines and derivatives was observed. Acrylaldehyde, 2-methylacrylaldehyde, and benzaldehyde N H imines have been identified as initial products from decomposition of the corresponding oxaziridines. 2,4,6-Trialkylhexahydro-l,3,5triazines, N,N'-dialkylidene-1 ,1 -diaminoalkanes, N,N'-diarylidene-1 ,1 -diaminoalkanes, and N-isobutylidene-2-methylpropenylamine were among the isolated products formed via the undetected alkyl aldehyde N H imines resulting from oxaziridine decomposition.

The formation of oxaziridines and the isomeric amides in equal amounts by the spontaneous autoxidation of several liquid imines via peroxyimidic acid intermediates is reported.