Formal dyotropic rearrangements of N-chloroamines catalysed by alumina

Rearrangement of N-chloro-2-azabicyclo[2.2.1]heptanes, [2.2.1]hept-5-enes, and [2.1.1]hexanes involving 1,2-migration of an sp3 or an sp2 carbon to nitrogen accompanied by 2,1-migration of chlorine occurs cleanly and efficiently on chromatographic alumina.