Additionally, the cyclic voltammetry measurements indicated the reduction potential of 2d is approximately at 1.28 V (vs SCE) (Fig. ), which is lower than the redox potential of the excited-state photocatalyst (fac-Ir(ppy)3, E1/2 (PC + /PC * ) = -1.73 V); suggesting that the reduction of 2d, leading to a reactive amidyl radical, is highly favorable in the reaction conditions. The reaction quantum yield was found to be  = 0.08 (Fig. ), which indicates that the radical chain pathway may not be operative in this transformation.