Aryloxo and thiolato vanadium complexes as chemical models of the active site of vanadium nitrogenase

This review describes recent advances in the synthesis and structural characterization of O- and S-rich ligated vanadium complexes with coligands relevant to the dinitrogen fixation process. Two classes of vanadium complexes: phenolato and thiolato are demonstrated, in aspect of ability to binding nitrogenous species. Examination of their X-ray structures allowed one to correlate the influence of O- and S-ligands at the vanadium site on the ability to bind N2-intermediates. In such simple systems, the interactions of the vanadium center with reduced and protonated N2 intermediates may help us develop an understanding of how nitrogenase functions.