Divergent CO Functionalization at Anionic Molybdenum Hydrides

By integrating a metal hydride with an alkali metal cation within an anionic molybdenum polyhydride system, [Cp*Mo(P^S)( μ ‐H) 3 Li] 2 ( 1, P^S = 1,2‐Cy 2 PC 6 H 4 S − ), we achieve the facile transformation of CO through divergent O‐silylation and C═C formation pathways. Key to this CO activation is the formation of an anionic carbonyl‐ligated (H)Mo─CO─Li species, generated upon H 2 elimination from 1 . This push–pull activation mode readily enables O‐silylation to form carbyne species. More significantly, the carbonyl moiety of the (H)Mo─CO─Li intermediate reacts with acyl chloride to form a C═C bond, accompanied by a hydride‐to‐CO migration, ultimately affording an enediolate fragment.