Synthesis and structure of a capped square-pyramidal five-metal oxo cluster, [Fe2Ru3(CO)14(.mu.4-O)]2-

Abstract

Main-group heteroatoms in low oxidation state organometallic cluster compounds are generally found in either interior positions or on the periphery as part of the cluster skeleton. Organometallic clusters containing the oxo ligand are much less numerous than organometallic carbides, nitrides, and sulfides. Until recently the highest coordination number of oxygen in an organometallic cluster was three. Recently we found four-coordinate oxygen in a metal butterfly cluster. We now describe the synthesis and characterization of a five-metal oxo cluster, (Fe{sub 2}Ru{sub 3}(CO){sub 14}({mu}{sub 4}-O)){sup 2{minus}}. The five-metal environment presents the possibility of a five-coordinate heteroatom which is situated nearly in the square-basal plane, or a four-coordinate heteroatom capping the square base.