Selectfluor-Bu4NI-Mediated C(sp3)-H Oxidation in Aqueous Media: Synthesis of Δ2-Isoxazolines from Oximes

The direct functionalization of an aliphatic C–H bond within a complex molecule through a free-radical pathway is a valuable tool in synthetic chemistry. Herein, we developed an efficient transition-metal-free approach to generate Δ2-isoxazolines from oximes by radical-mediated C(sp3)–H oxidation. Investigation of the mechanism suggested that in the presence of Selectfluor and Bu4NI, the homolysis of the in situ formed O–I bond generated an iminoxyl radical that facilitated subsequent 1,5-H transfer and C(sp3)–H oxidation.