Palladium-catalyzed synthesis of quinolin-2(1H)-ones: the unexpected reactivity of azodicarboxylate

Quinolin-2(1H)-one is a useful structure unit present in a wide range of natural products and pharmaceuticals. A Pd(II)-catalyzed synthesis of quinolin-2(1H)-ones from quinoline N-oxides was developed with azodicarboxylates which act as both the activating agent and oxidant. The reaction proceeded under mild conditions and no protection against air and moisture was needed.