A simple and mild Cu-catalyzed oxidative three-component oxidative Ugi-type method for the synthesis of a variety of substituted imides has been developed. In this direct imidation approach, benzoyl peroxide serves as both the oxidant and the carboxylate source, allowing not only the functionalization of C(sp³)–H bonds in α-position to an amine but also benzylic substrates. This procedure presents a wide substrate-type and functional group tolerance. Moreover, the mildness of the method permitted us to extend its application to the late stage functionalization of complex natural products such as the alkaloids brucine and strychnine, leading to interesting highly functionalized imide derivatives. On the basis of experimental and computational studies, a plausible mechanism has been proposed.