In the presence of sufficient light and water the major limiting factor to plant growth is bioavailable nitrogen, ammonia. Nitrogen fixation in plants occurs under ambient conditions while industrial production of ammonia requires conditions so energy intensive they consume approximately 1% of the world's energy production annually. The iron-molybdenum cofactor (FeMoco) of the nitrogenase enzyme is the site of dinitrogen reduction to ammonia. The complex structure of the active site of nitrogenase comprises a bicapped trigonal prism of seven iron atoms, one molybdenum atom, and nine sulfur atoms. Recently, a high-resolution single crystal X-ray structure revealed an interstitial atom at the center of the cluster core which is most likely a nitrogen atom. Such a cluster was unprecedented in iron chemistry. Herein, a synthetic route to iron-nitride clusters with electronic structures similar to the cofactor of the nitrogenase is presented, and synthetic schemes utilizing these ferric-nitride clusters as scaffolds for the construction of a cluster similar to the cofactor are proposed. New synthetic methodologies relevant to synthetic analogues of the cofactor of nitrogenase are being developed.
