A SmI-mediated reductive cyclisation reaction using the trifluoroacetamide group as the radical precursor.

A samarium(II)-mediated reductive cyclisation reaction with the aminoketyl radical from the trifluoroacetamide group for synthesising 2-trifluoromethylindolines was developed. This reaction is the first example of using an acyclic amide group, which is considered difficult to react with SmI, in a reductive cyclisation. Additionally, the conversion of the obtained product into 2-trifluoromethylindole was achieved.