In search of an easy fix for nitrogen

Industrial nitrogen fixation is performed on a vast scale by the Haber–Bosch process, which uses a solid-state iron catalyst at very high temperatures and pressures. Synthetic chemists have searched for decades for small metal-containing complexes to catalyse the transformation of nitrogen into ammonia in less extreme conditions, taking their lead from the nitrogenases found in plants and bacteria. To that end Jonas Peters and colleagues describe a tris(phosphine)borane-supported iron complex that catalyses the reduction of nitrogen into ammonia under mild conditions with reasonable efficiency. This suggests that a single iron site is sufficient for mediating nitrogen fixation, in line with recent biochemical and spectroscopic data that point to iron rather than the molybdenum also present in the FeMo cofactor or nitrogenase as the site of nitrogen binding and activation.