Bisphosphonium Salt-Catalyzed C-C Bond Cleavage of Vicinal Diols under Visible-Light Irradiation.

A mild, metal-free photocatalytic method for the oxidative cleavage of vicinal diols was developed by using bisphosphonium salt photocatalysts under visible light. The reaction proceeded efficiently at room temperature in an air atmosphere, achieving the selective cleavage of C-C bonds in 1,2-diols to afford aldehydes and ketones in good to high yields. Mechanistic studies indicated that the reaction mechanism involved a free-radical pathway.