Decreasing the Bond Order between Vanadium and Oxo Ligand to Form 3d Schrock Carbynes.

Preserving vanadium in a high oxidation state during chemical transformations can be challenging due to the oxidizing nature of V(+5) species. Oxo and similar isoelectronic ligands have been utilized to stabilize V(+5) by extensive π-donation. However, decreasing the bond order between V and the oxo ligand often results in a reduction of the metal center. Herein, we report a unique transformation involving anionic V(+5) alkylidene that converts a V(+5) oxo complex to a V(+5) alkylidyne in three steps without altering the oxidation state of the metal center. This method has been used to obtain rare 3d Schrock carbynes, which provide easy and scalable access to V(+5) alkylidynes.