Fig. 5.

Mechanistic studies. a Observation of both dienone and enone products before reaction completion. b Identification of γ-TEMPO-substituted enone 12. c Dehydrogenation of γ-TEMPO-substituted enone to dienone. d The radical probe experiment. e The dehydrogenation of 1a (green) to 2a (red). f Kinetic time course of the dehydrogenation of 1a (green) to 2a (red) and 2aʹ (blue) using a lower amount of TEMPO. ^*GC yields using n-dodecane as an internal standard. ^†Yield determined by ¹H NMR analysis