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The palladium‐catalyzed reaction of aromatic amides with maleimides results in the formation of a double C−H bond activation product, which occurs at both the benzylic and meta positions. Computational chemistry studies suggest that the first C−H bond activation unfolds via a six‐membered palladacycle, maleimide insertion, protonation of the Pd−N bond, and then activation of the meta C−H bond. The process concludes with reductive elimination, producing an annulation product. The energy decomposition analysis (EDA) showed that the deformation energy favors the ortho C−H bond activation process. However, this route is non‐productive. The interaction energy controls the site where the maleimide is inserted into the Pd−C(sp3) bond, which determines its site selectivity. The energetic span model indicates that the meta C−H bond activation step is the one that determines the turnover frequency. Regarding the directing group, it has been concluded that the strong Pd−S bonding and the destabilizing effect of the deformation energy allow the 2‐thiomethylphenyl to function effectively as a directing group. [ABSTRACT FROM AUTHOR]

The palladium‐catalyzed [3+2] annulation of aromatic amides with maleimides via the activation of ortho benzylic C−H and meta C−H bonds is reported. Carboxamide and anilide type substrates that contain a 2‐methylthiophenyl group both participate in this [3+2] annulation, indicating that the presence of a 2‐methylthiophenyl directing group is a key for the success of the reaction. The first C−H bond activation at the benzylic C−H bond is followed by a second C−H bond activation at the meta C−H bond to give five‐membered cyclic products. The cleavage of these C−H bonds is irreversible. [ABSTRACT FROM AUTHOR]