Triiodide-Mediated δ-Amination of Secondary C-H Bonds.

The Cδ -H amination of unactivated, secondary C-H bonds to form a broad range of functionalized pyrrolidines has been developed by a triiodide (I3 (-) )-mediated strategy. By in situ 1) oxidation of sodium iodide and 2) sequestration of the transiently generated iodine (I2 ) as I3 (-) , this approach precludes undesired I2 -mediated decomposition which can otherwise limit synthetic utility to only weak C(sp(3) )-H bonds. The mechanism of this triiodide-mediated cyclization of unbiased, secondary C(sp(3) )-H bonds, by either thermal or photolytic initiation, is supported by NMR and UV/Vis data, as well as intercepted intermediates.