Palladium-catalyzed oxidative domino carbocyclization-carbonylation-alkynylation of enallenes.

An oxidative carbocyclization-carbonylation-alkynylation reaction cascade has been developed using catalytic amounts of palladium(II) salts. The domino reaction proceeds efficiently, giving the corresponding ynones in good to excellent yields under operationally simple conditions. A wide range of aromatic and aliphatic terminal alkynes with various functional groups are tolerated under the reaction conditions.