An IrVO Cluster Catalytically Oxidizes Four CO Molecules: Importance of Ir-V Multiple Bonding.

The generation and characterization of multiple metal-metal (M-M) bonds between early and late transition metals is vital to correlate the nature of multiple M-M bonds with the related reactivity in catalysis, while the examples with multiple M-M bonds have been rarely reported. Herein, we identified that the quadruple bonding interactions were formed in a gas-phase ion IrV with a dramatically short Ir-V bond. Oxidation of four CO molecules by IrVO is a highly exothermic process driven by the generation of stable products IrV and CO, and then IrV can be oxidized by NO to regenerate IrVO. This finding overturns the general impression that vanadium oxide clusters are unwilling to oxidize multiple CO molecules because of the strong V-O bond and that at most two oxygen atoms can be supplied from a single V-containing cluster in CO oxidation. This study emphasizes the potential importance of heterobimetallic multiple M-M bonds in related heterogeneous catalysis.