[3,3] Sigmatropic Shifts and Applications of Hydroxylamine Derivatives

[3,3] sigma shift is one of classic reactions in organic chemistry. Since its discovery, the reactions have been expanding to different types and widely used in the fields of organic and pharmaceutical synthesis. Because the N-O bond strength of hydroxylamine derivatives is weak and easy to break, their [3,3] sigma shift can be carried out under mild conditions to afford complex molecules containing hydroxyl and amino groups. In recent years, more and more attention has been paid to these reactions. The [3,3] sigma shift rearrangements of hydroxylamine derivatives, including N-aryl-O-alkenylhydroxylamines, N,O-diaryl hydroxylamines, N,O-dialkenyloxyamines, N-alkenyl-O-arylhydroxyamines, and N-alkyl-O-acylhydroxyamines are reviewed, and a new prospect for the [3,3] sigma shifts of hydroxylamine derivatives and their future development are put forward.