Partial synthetic models of FeMoco with sulfide and carbyne ligands: Effect of interstitial atom in nitrogenase active site
Linh Le, Gwendolyn A. Bailey, Anna G. Scott, Theodor Agapie
Abstract
Significance Nitrogen, a common component of biomolecules, is sourced from abundant dinitrogen in the atmosphere through conversion to ammonia. Organisms capable of fixing N 2 employ nitrogenases, metalloproteins that display metal-sulfide clusters that facilitate electron transfers and substrate activation. The site of N 2 conversion to NH 3 is FeMco (M = Mo, Fe, or V), a cluster of notable complexity in bioinorganic chemistry, which displays an unusual interstitial carbon ligand. The function of this bridging ligand remains unclear, and systematic structure-function studies with bridging C-donors are challenged by a lack of synthetic methods for analogous clusters. Herein, we report the first synthetic cluster that models a cubane moiety of FeMco bearing a chelating carbyne ligand and related structure-property studies.