AN EFFICIENT AND SELECTIVE PALLADIUM-CATALYZED OXIDATIVE DICARBONYLATION OF ALKYNES TO ALKYL-MALEIC OR ARYL-MALEIC ESTERS

Terminal alkyne dicarbonylation can be readily effected under mild con ditions by treating alkynes with carbon monoxide and alcohols or water at 25-80 degrees C in the presence of Pdl(2), KI and air, with unprec edented catalytic efficiency. Dicarbonylated products are mainly malei c esters or acids and their ring-chain tautomers. The latter are forme d to a large extent at room temperature. Reaction pathways are discuss ed.