Versatile Synthesis of Pyrrole-2-acetic Esters and (Pyridine-2-one)-3-acetic Amides by Palladium-Catalyzed, Carbon Dioxide-Promoted Oxidative Carbonylation of (Z)-(2-En-4-ynyl)amines

The oxidative carbonylation of readily available (Z)-(2-en-4-ynyl)amines, catalyzed by the PdI 2 -KI system, selectively afforded in satisfactory yields (40-95 %) either pyrrole-2-acetic ester or (pyridine-2-one)-3-acetic amide derivatives, depending on the susbtitution pattern of the substrate and the reaction conditions. The presence of an excess of carbon dioxide proved in most cases to be beneficial to both the reaction rate and product selectivity.