Molecular nitrogen (N2) and carbon monoxide (CO) have the two strongest bonds in chemistry and present significant challenges in developing new transformations that exploit these two abundant feedstocks. At the core of this objective is the discovery of transition-metal compounds that promote the six-electron reductive cleavage of N2 at ambient temperature and pressure and also promote new nitrogen–element bond formation. Here we show that an organometallic hafnium compound induces N2 cleavage on the addition of CO, with a simultaneous assembly of new nitrogen–carbon and carbon–carbon bonds. Subsequent addition of a weak acid liberates oxamide, which demonstrates that an important agrochemical can be synthesized directly from N2 and CO. These studies introduce an alternative paradigm for N2 cleavage and functionalization in which the six-electron reductive cleavage is promoted by both the transition metal and the incoming ligand, CO, used for the new bond formations.
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Financial support was provided by the Director, Office of Basic Energy Sciences, Chemical Sciences Division, of the US Department of Energy (DE-FG02-05ER15659) and the Frasch Foundation administered by the American Chemical Society.
The authors declare no competing financial interests.
Supplementary information (PDF 496 kb)
Crystallographic data for compound 2-N2 (corrected 8 January 2010) (CIF 24 kb)
Crystallographic data for compound 2-N2C2O2 (CIF 26 kb)
Crystallographic data for compound 3 (CIF 24 kb)
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Knobloch, D., Lobkovsky, E. & Chirik, P. Dinitrogen cleavage and functionalization by carbon monoxide promoted by a hafnium complex. Nature Chem 2, 30–35 (2010). https://doi.org/10.1038/nchem.477
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