Intramolecular trans-Carbocarbonation of Carbon-Carbon Triple Bonds by an anti-Carbopalladation/Suzuki Coupling Cascade

An intramolecular palladium-catalyzed trans-carbocarbonation cascade is presented that consists of a formal anti-carbopalladation of an internal carbon-carbon triple bond terminated by a Suzuki cross-coupling reaction. The key to success in obtaining the anti-geometry of the emerging double bond is the use of alkyne units with substituents that avoid beta-hydride elimination (e. g. tert-butyl or silyl). The products, involving tetrasubstituted double bonds embedded in a seven- or eight-membered ring system, are formed in moderate to good yields.