Synthesis of a Fe 3 -Carbyne Motif by Oxidation of an Alkyl Ligated Iron-Sulfur (WFe 3 S 3 ) Cluster.

The presence of a carbide ligand in the active site of nitrogenases remains an unusual example of organometallic chemistry employed by a protein. Carbide incorporation into the MFe 7 S 9 C cluster involves complex biosynthesis, but analogous synthetic methodologies are limited. Herein, we present a new synthetic strategy for incorporating carbon based bridging ligands into iron-sulfur clusters. Starting from a halide precursor, a WFe 3 S 3 cluster displaying three terminal alkyl ligands and an open Fe 3 face was prepared. Oxidation results in loss of alkane and formation of a μ 3 -carbyne. Characterization of these clusters and mechanistic studies are presented.