Molecular Complexes for Catalytic Ammonia Oxidation to Dinitrogen and the Cleavage of N−H Bonds

Abstract The molecular complexes described herein use main‐group elements or transition metals to control the stoichiometric cleavage of N−H bonds of ammonia (NH 3 ) and/or catalyze chemical and electrochemical NH 3 oxidation to dinitrogen (N 2 ). We highlight the phenomenon of coordination‐induced bond weakening and a variety of N−H bond cleavage mechanisms of NH 3 including H atom abstraction, inter‐ and intra‐molecular deprotonation reactions, oxidative addition, and σ ‐bond metathesis that have been demonstrated with molecular systems. We provide an overview of the molecular complexes reported for the rapidly developing field of NH 3 oxidation catalysis to form N 2 . These systems exhibit several diverse structure types and innovative ligands to support transition metals capable of activating NH 3 and mediating a challenging chemical transformation that requires breaking strong N−H bonds and forming an N−N bond en route to N 2 formation.