Synthesis of Diones via Visible Light‐Induced Oxidation of α‐Hydroxy Ketone Derivatives.

A visible light‐induced oxidation of α‐hydroxy ketone derivatives is reported, which is carried out in the presence of CBrCl3 and ruthenium photocatalyst, and the corresponding diketones are obtained in 49‐95% yields. This reaction has the advantages of moderate to excellent yields, good functional group tolerance, and mild reaction condition. The free radical reaction process was confirmed by the addition of radical scavenger 2,2,6,6‐tetramethylpiperidi‐1‐oxy (TEMPO). The fluorescence quenching experiment indicated that CBrCl3 was participated in the oxidation quenching cycle. [ABSTRACT FROM AUTHOR]