Ir(III)-Catalyzed C(sp²)-H Amidation of 2-Aroylimidazoles with 2,2,2-Trichloroethoxycarbonyl Azide (TrocN₃)

The Ir(III)-catalyzed ortho-C-H amidation of 2-aroylimidazole derivatives with 2,2,2-trichloroethyl azide (TrocN₃) as an amidating reagent is reported. The reaction proceeds smoothly, even at room temperature, and various important functional groups are tolerated. The results of deuterium-labeling experiments indicate that C-H bond cleavage is irreversible and does not appear to be the rate-determining step. The presence of an electron-donating group on the phenyl ring in the 2-aroylimidazole results in a dramatic acceleration in the reaction.