Stereoselective Radical Azidooxygenation of Alkenes

Radical azidooxygenation of various alkenes is described. A readily prepared N3-iodine(III) reagent acts as a clean N3-radical precursor. Radical generation is achieved with TEMPONa acting as a mild organic reducing reagent. The C-radical generated after N3-radical addition is efficiently trapped by in situ generated TEMPO. Yields are good to excellent, and for cyclic systems azidooxygenation occurs with excellent diastereoselectivity.