Conversion of aryl CO to CC bond through a UV light activation/TEMPO oxidation cascade reaction

Metal free conversion of aryl CO to CC bond through a photochemical rearrangement/oxidation cascade reaction is described. Irradiation of O-acetyl aryloxy benzene derivatives in benzene solution undergoes a unique photochemical rearrangement reaction to afford the ketal compounds, which are sequentially oxidized by 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) to yield the diketone compounds.