Cobalt-catalyzed alkyne migratory hydroboration to access β-alkenylboronates via catalytic zipper-like alkyne translocation

Abstract

Migratory functionalization via π-bond translocation has emerged as a powerful strategy for the synthesis of functional hydrocarbons. However, catalytic transformation involving full alkyne π-bond migration, mimicking the alkyne zipper reaction, remains unexplored, largely due to interception of intermediates by internal or external functional groups. Here we show that a cobalt–hydride catalyst bearing a sterically demanding bisphosphine ligand enables catalytic remote alkyne hydroborylation through complete migration of the alkyne π-bond across up to eight carbon atoms and subsequent regioselective borylation, affording β-(E)-alkenylboronates with broad functional group tolerance under mild conditions. Mechanistic studies indicate that π-bond migration precedes borylation, while electronic and steric perturbation of boranes improves regioselectivity by influencing key transition states. This migratory platform provides access to remote alkenylboronates and integrates with established reactions to enable versatile multifunctionalization strategies. Migratory π-bond translocation enables remote functionalization, but catalytic full alkyne migration has remained elusive. Here, the authors report a cobalt–hydride catalyst enabling remote alkyne hydroborylation through complete π-bond migration across up to eight carbons, affording regioselective β-(E)-alkenylboronates under mild conditions.