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Visible-Light-Promoted Indole C-3 Formylation Using Eosin Y as a Photoredox Catalyst

Yin Zhao, Hongfang Li, Shan Yin, Yandan Wu, Guanghui Ni*

*School of Chinese Materia Medica, Yunnan University of Chinese Medicine, No.1076 Yuhua Road, Kunming 650500, P. R. of China, Email:

Y. Zhao, H. Li, S. Yin, Y. Wu, G. Ni, Synlett, 2022, 33, 659-663.

DOI: 10.1055/a-1777-2556

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Eosin Y catalyzes a visible-light-mediated C-3 formylation of indole in the presence of tetramethylethylenediamine as a carbon source and air as an oxidant under mild conditions. This protocol tolerates a broad range of functional groups and provides 3-formylated indoles with good yields.

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Key Words

visible light, eosin Y, oxygen, indoles, formylation, photochemistry

ID: J72-Y2022