POCl3‐Promoted Trifluoromethylthiolation‐Based Vicinal Bifunctionalization of Indoles with CF3SO2Na

An efficient trifluoromethylthiolation‐based vicinal bifunctionalization of indoles with sodium trifluoromethanesulfinate in the presence of phosphorus oxychloride were achieved to introduce a chlorine atom into the 2‐position under transition‐metal‐free and mild conditions. The protocol could also extend to other sodium perfluoroalkanesulfinates or phosphorus oxybromide. The possible pathway was proposed based on the experimental results. Direct trifluoromethylthiolation‐based vicinal bifunctionalization of indoles with sodium trifluoromethanesulfinate in the presence of phosphorus oxychloride was achieved, which affords another functional group (chloro or bromo) for further transformation.