Catalytic synthesis of oligoene and enyne derivatives through carbometalation of internal alkynes.

A number of new synthetic methods for pi-conjugated oligoene and enyne compounds are described. Thus, diene and higher oligoene derivatives are selectively constructed by palladium-catalyzed arylation reactions of internal alkynes in the presence of arylboronic acids or alkenes as terminators. In contrast, the synthesis of various enyne derivatives is achieved effectively by homo- or cross dimerization of alkynes under rhodium catalysis.