Synthesis of 5H-Dibenzo[c,e]azepine-5,7(6H)-diones from Benzamides via Palladium-Catalyzed Double C-H Bond Activation.

A convenient and efficient method for the synthesis of 5H-dibenzo[c,e]azepine-5,7(6H)-diones from simple and readily available benzamides is described in this work. The palladium-catalyzed homocoupling of benzamides occurred via ortho-selective double C-H bond activation using the simplest amide CONH2 as a directing group. The subsequent intramolecular condensation reaction proceeded smoothly to produce 5H-dibenzo[c,e]azepine-5,7(6H)-diones in satisfactory to excellent yields in one pot.