N-4-Pentenyl- and N-5-hexenyl-N-methylhydroxylamine cyclized under mil
d conditions in a reverse Cope elimination reaction to give 1,2-dimeth
ylpyrrolidine N-oxide and 1,2-dimethylpiperidine N-oxide, respectively
. The reaction was shown to be concerted and thermodynamically control
led. The scope of this novel cyclization is discussed, and comparisons
are made with the closely related and previously reported cyclization
of monosubstituted alkenylhydroxylamines to give cyclic hydroxylamine
s.