A stable and recyclable Z-scheme g-C3N4/rGO/BiVO4 heterojunction photocatalyst for site-selective C-3 formylation of indoles with methanol as a formyl source under visible light

A stable and recyclable Z-scheme g-C3N4/rGO/BiVO4 heterojunction photocatalyst was constructed by a facile two-step hydrothermal procedure. The photocatalyst was used for the synthesis of C-3 formylated indoles from indoles with methanol as an atom-economical formyl source for the first time, and 30% g-C3N4/rGO/BiVO4 exhibited superior photocatalytic efficiency. Quenching experiments showed that the photogenerated electrons and holes were the main photoactive species to achieve the reaction. This formylation reaction has the advantages of exceptional functional group tolerance, reusable photocatalysts, and mild reaction conditions. Gram scale synthesis indicated the future prospects of this strategy for real applications.

Automated summary

A stable and recyclable Z-scheme g-C3N4/rGO/BiVO4 heterojunction photocatalyst was successfully synthesized using a facile two-step hydrothermal procedure. This photocatalyst exhibited superior photocatalytic efficiency in the synthesis of C-3 formylated indoles using methanol as a formyl source. Quenching experiments confirmed that photogenerated electrons and holes were the main active species for the reaction. The formylation reaction demonstrated exceptional functional group tolerance, reusable photocatalysts, and mild reaction conditions.