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-C3N4) 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.