Biological and synthetic nitrogen fixation

This article deals with biological and synthetic nitrogen fixation. The first part gives an overview over the structure and function of nitrogenase, with an emphasis on discussing the available mechanistic information on the N 2 -to-NH 3 conversion in the enzyme. In the second part, the available, catalytically active model small-molecule model systems of nitrogenase are reviewed. Again, the focus is put on describing the available mechanistic information regarding to the conversion of dinitrogen to ammonia. Having considered the enzyme and the available inorganic models, common trends in the bonding, activation, and conversion of N 2 to ammonia are identified and lessons derived from the complementary study of these systems are formulated.