Direct C-H amination of indoles enabled by tert-butyl chlorosulfonylcarbamate with diisopropylethylamine.

Herein, we report a direct and catalyst-free C-H amination for the construction of C-N bonds at the C2 position of indoles. This method employs readily available tert-butyl chlorosulfonylcarbamate and diisopropylethylamine under very mild conditions, proceeds rapidly without indole prefunctionalization, and enables the efficient synthesis of diverse Boc-protected 2-aminoindole derivatives with a broad substrate scope.