Rearrangement of β-Chloro <i>N</i>-Oxides to Hydroxylamines: Opening of the Oxazetidinium Intermediate by Different Nucleophiles

The rearrangement of β-chloro N-oxides to hydroxylamines is stereospecific in accord with the presence of a cyclic oxazetidinium intermediate. The latter opens with a range of nucleophiles (carboxylates, cyanide, azide, and thiols)