[3+2] Photooxygenation of aryl cyclopropanes via visible light photocatalysis

We report that Ru(bpz)32+ is an excellent sensitizer for the photooxygenation of aryl cyclopropanes upon irradiation with visible light. The effectiveness of this photocatalyst enables the synthesis of a range of five-membered endoperoxides in excellent yield with quite low (0.5 mol %) catalyst loadings even when standard household light sources are utilized.