Heterogeneous Photocatalytic C-H Functionalization of Indoles with Diazo Compounds Enabled by Carbon Nitride.

Herein, we reported the heterogeneous photocatalytic C-H alkylation of indoles with diazo compounds using graphitic carbon nitride (g-CN) as the photocatalyst. The reaction was carried out under a simple operation and mild conditions. In addition, the catalyst was found to be stable and reusable after five reaction cycles. The photochemical reaction proceeds via an intermediary of a carbon radical, which is generated from diazo compounds through a visible-light-promoted proton-coupled electron transfer (PCET) process.