Allylic amidation of olefins by ene reaction of acylnitroso compounds generated in situ by oxidation of hydroxamic acids

A one-pot allylic amidation procedure, which employs the ene reaction of ac ylnitroso compounds 2 with electron-rich olefins 3a,b, is presented; the ac ylnitroso enophile is generated in situ by oxidation of hydroxamic acids 1 with iodosobenzene diacetate. The resulting N-allylhydroxamic acids 4 (ene products) are quantitatively acetylated for ease of handling; as an example , the reduction of the acetylated derivative 5b by samarium diiodide was ca rried out to afford the N-allyl amide 6b in quantitative yields.