Palladium- And Nickel-Catalyzed Coupling Reactions Of Alpha-Bromoalkenylphosphonates With Arylboronic Acids And Lithium Alkenylborates

The coupling reaction of the alpha-bromoalkenylphosphonates with organoboranes was investigated. The palladium-catalyzed arylation took place successfully with arylboronic acids, while alkenylation proceeded with lithium alkenylborates and a nickel catalyst. In addition, an intramolecular Diels-Alder reaction of the diene prepared by the alkenylation afforded the corresponding adduct.