Cu(I)-Catalyzed Cross-Coupling of Conjugated Ene-yne-ketonesand Terminal Alkynes: Synthesis of Furan-Substituted Allenes.

A new method for the synthesis offuran-substituted allenes viaCu(I)-catalyzed coupling of conjugated ene-yne-ketones with terminalalkynes has been developed. A wide range of functional groups aretolerated, and the products are obtained in good to excellent yieldsunder mild conditions. A copper carbene migratory insertion is proposedas the key step in this transformation with conjugated ene-yne-ketonesas carbene precursors. [ABSTRACT FROM AUTHOR]