Collect. Czech. Chem. Commun. 1979, 44, 2221-2229

Structure reexamination of aliphatic nitrones and their dimers

Břetislav Princ and Otto Exner

Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, 166 10 Prague 6


The structure of some compounds reported in the literature as nitrones II has been reexamined using mainly the 1H NMR and mass spectroscopies. The nitrone structure has been confirmed for the condensation products of N-alkylhydroxylamines with aldehydes (IIf) or ketones (IIj,l,m), as well as for the products of alkylation of aldoximes with benzyl chloride (IId,h). Other similar alkylation reactions yield generally a mixture of the nitrone and the dimeric oxazolidine derivative (Va,b,e), in addition to the O-alkylated oxime (VI). The nitrone is assumed to be the primary product in any case, its subsequent dimerization is promoted either by the alkaline medium or by the presence of a phenyl group as in Vg,k.