Red-light mediated formylation of indoles using a helical carbenium ion as a photoredox catalyst
Nand Lal1, Deepshikha1, Puja Singh1
1Department of Chemistry, Indian Institute of Technology Ropar (IIT Ropar), Rupnagar, Punjab-140 001, India. aslam.shaikh@iitrpr.ac.in.
Abstract:
Low-energy photoredox catalysis has gained significant attention in developing organic transformations due to its ability to achieve high penetration depth and minimum health risks. Herein, we disclose a red-light (λ = 640 nm)-mediated C-3 formylation of indoles utilizing a helical carbenium ion as a photocatalyst and 2,2-dimethoxy-N,N-dimethylethanamine as a formylating source. These protocols exhibit a broad substrate scope under mild conditions with efficient scalability for the synthesis of C-3 formylated indoles.
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