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Cp*Ir( iii ) complexes have been shown to be effective for the halogenation of N , N -diisopropylbenzamides with N -halosuccinimide as a suitable halogen source. The optimized conditions for the iodination reaction consist of 0.5 mol% [Cp*IrCl 2 ] 2 in 1,2-dichloroethane at 60 °C for 1 h to form a variety of iodinated benzamides in high yields. Increasing the catalyst loading to 6 mol% and the time to 4 h enabled the bromination reaction of the same substrates. Reactivity was not observed for the chlorination of these substrates. A variety of functional groups on the para -position of the benzamide were well tolerated. Kinetic studies showed the reaction dependence is first order in iridium, positive order in benzamide, and zero order in N -iodosuccinimide. A KIE of 2.5 was obtained from an independent H/D kinetic isotope effect study. Computational studies (DFT-BP3PW91) indicate that a CMD mechanism is more likely than an oxidative addition pathway for the C–H bond activation step. The calculated functionalization step involves an Ir( v ) species that is the result of oxidative addition of acetate hypoiodite that is generated in situ from N -iodosuccinimide and acetic acid.