Abstract Ball milling techniques have been applied in the development of a mechanosynthesis of [Cp*Co(CO)I 2 ], which proved highly efficient as catalyst in mechanochemical C−H bond amidations of indoles in a mixer ball mill. A wide range of amidated products is obtained in excellent yields. Compared to the solution‐based methods, the procedure opens a more feasible and environmentally‐friendly access to both the cobalt(III) catalyst and 2‐amidated indoles. magnified image