Palladium‐ and Nickel‐Catalyzed Coupling Reactions of α‐Bromoalkenylphosphonates with Arylboronic Acids and Lithium Alkenylborates

Abstract The coupling reaction of the α‐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.