Arylthianthrenium Salts Enabled Palladium-Catalyzed Regioselective Arylation: Access to Value-Added 7-Azaindoles
Siddhartha Paul1, Vishal Talukdar1, Diship Srivastava1
1Department of Chemistry and Chemical Biology, Indian Institute of Technology (Indian School of Mines), Dhanbad-826004, India.
Abstract:
A step-economic and efficient palladium-catalyzed protocol for regioselective C-2 arylation of 7-azaindoles with arylthianthrenium salts has been developed under base- and ligand-free conditions. The reaction proceeds smoothly with broad substrate scope, requires low catalyst loading, exhibits excellent functional group tolerance, and provides C-2 arylated products in moderate to excellent yields. Moreover, given the ready availability of arylthianthrenium salts from simple arenes, this strategy offers a valuable platform for the late-stage functionalization of structurally complex and bioactive molecules. The origin of the observed regioselectivity has been elucidated through density functional theory (DFT) calculations.
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