Iron dinitrogen complexes and nitrogen fixation with tris(phosphine)alkyl ligands

Abstract

The interstitial light atom of the FeMo-cofactor of MoFe-Nitrogenase has recently been identified as a C-atom, and hypotheses regarding its possible role/s warrant synthetic model studies. We have previously suggested that one role this structural unit may play is to modulate an Fe-C interaction upon substrate binding and redn. at the cofactor. To explore this idea, we have begun to target ligands whereby a comparatively loosely bound C-atom is installed on an Fe center in a position trans to where substrates such as nitrogen bind. I will discuss the fundamental coordination chem. of these ligands at iron and other late first row metals, and will describe their efficacy towards the catalytic redn. of dinitrogen to ammonia.