Stephens, David N.Szilagyi, Robert K.Roehling, Paige N.Arulsamy, NavamoneyMock, Michael T.2023-02-032023-02-032023-01Stephens, D. N., Szilagyi, R. K., Roehling, P. N., Arulsamy, N., Mock, M. T., Angew. Chem. Int. Ed. 2023, 62, e202213462; Angew. Chem. 2023, 135, e202213462.1433-7851https://scholarworks.montana.edu/handle/1/17689This is the peer reviewed version of the following article: [Catalytic Ammonia Oxidation to Dinitrogen by a Nickel Complex. Angewandte Chemie International Edition 62, 1 (2023)], which has been published in final form at https://doi.org/10.1002/anie.202213462. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions: https://authorservices.wiley.com/author-resources/Journal-Authors/licensing/self-archiving.html#3.We report a nickel complex for catalytic oxidation of ammonia to dinitrogen under ambient conditions. Using the aryloxyl radical 2,4,6-tri-tert-butylphenoxyl (tBu3ArO⋅) as a H atom acceptor to cleave the N−H bond of a coordinated NH3 ligand up to 56 equiv of N2 per Ni center can be generated. Employing the N-oxyl radical 2,2,6,6-(tetramethylpiperidin-1-yl)oxyl (TEMPO⋅) as the H-atom acceptor, up to 15 equiv of N2 per Ni center are formed. A bridging Ni-hydrazine product identified by isotopic nitrogen (15N) studies and supported by computational models indicates the N−N bond forming step occurs by bimetallic homocoupling of two paramagnetic [Ni]−NH2 fragments. Ni-mediated hydrazine disproportionation to N2 and NH3 completes the catalytic cycle.en-UScopyright Wiley 2023https://web.archive.org/web/20200106202133/https://onlinelibrary.wiley.com/library-info/products/price-listshttp://web.archive.org/web/20190530141919/https://authorservices.wiley.com/author-resources/Journal-Authors/licensing/self-archiving.htmlcatalytic ammonia oxidationnickel complexArticle