Palladium-Catalyzed Regioselective Domino Cyclization of Cyclohexadienones

A mild and efficient Pd-catalyzed arylative domino carbocyclization of cyclohexadienone-containing 1,6-enynes is described. The reaction tolerates a variety of functionalized boronic acids to afford a cis-fused bicyclic framework containing an α,β-unsaturated ketone with excellent regio- and diastereoselectivity in good yields. The tandem process proceeds with β-arylation of propargylic ether followed by conjugate addition of a vinyl palladium intermediate and subsequent protonolysis of a palladium enolate.