Dinitrogen coordination chemistry: on the biomimetic borderlands.

Biological nitrogen fixation by the nitrogenase enzymes has long been a touchstone for dinitrogen chemists.1,2 Both the enzymatic reduction and protonation of N2 mediated by these metalloenzymes (eq 1)3,4 and the industrial hydrogenation of N2 exemplified by the Haber-Bosch process (eq 2)5-7 employ transition metal-based catalysts to accelerate the thermodynamically feasible production of ammonia.