Abstract
Metallonitrenes (M–N) are complexes with a subvalent atomic nitrogen ligand that have been proposed as key reactive intermediates in nitrogen atom transfer reactions. However, in contrast to the common classes of nitride complexes (M≡N) and organic nitrenes (R–N), structurally and spectroscopically well defined ‘authentic’ metallonitrenes with a monovalent atomic nitrogen ligand remain elusive. Here we report that the photolysis of a platinum(ii) pincer azide complex enabled the crystallographic, spectroscopic, magnetic and computational characterization of a metallonitrene that is best described as a singly bonded atomic nitrogen diradical ligand bound to platinum(ii). The photoproduct exhibits selective C–H, B–H and B–C nitrogen atom insertion reactivity. Despite the subvalent metallonitrene character, mechanistic analysis for aldehyde C–H amidation shows nucleophilic reactivity of the N-diradical ligand. Ambiphilic reactivity of the metallonitrene is indicated by reactions with CO and PMe3 to form isocyanate and phosphoraneiminato platinum(ii) complexes, respectively.
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Data availability
All data generated and analysed during this study are included in this Article and its Supplementary Information or are available from the corresponding author upon reasonable request. Crystallographic data for the structures reported in this article have been deposited at the Cambridge Crystallographic Data Centre, under deposition numbers CCDC 1973273 ([PtCl(N(CH2CH2PtBu2)2)] (A)), 1973274 ([PtCl(PNP)] (B)), 1973275 ([PtH(PNP)] (C)), 1973276 ([PtOTf(PNP)] (D)), 1973277 (1), 1973278 (2), 1973279 (3), 1994705 (5), 1973280 (6), 1973281 (7), 1973282 (8), 1973283 (9). Copies of the data can be obtained free of charge via https://www.ccdc.cam.ac.uk/structures/.
Change history
12 February 2021
A Correction to this paper has been published: https://doi.org/10.1038/s41557-020-00613-x
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Acknowledgements
The authors thank the ERC (Grant Agreement 646747) and the German Research Council (DFG grants 389479699/RTG2455, SCHN950/6-1 and SL104/10) for funding. J. M. Matys is acknowledged for help with synthetic work and single-crystal growth of (Pt(OTf)(PNP)). C.W. thanks R. Herbst-Irmer for helpful discussions. Quantum chemical calculations of the Frankfurt group were performed at the Center for Scientific Computing (CSC) Frankfurt on the Goethe-HLR computer cluster.
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S.S. and M.C.H. generated the project and designed its concept. S.S. supervised the experimental study and M.C.H the quantum chemical study. J.S performed synthetic and spectroscopic work. J.A. carried out spectroscopic and crystallographic work. C.W. performed crystallographic characterization. B.d.B., M.D. and H.V. carried out quantum chemical calculations. D.H. carried out the magnetic characterization supervised by J.v.S. All authors discussed the results in detail and commented on the manuscript.
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Supplementary information
Supplementary Information
Experimental details and spectroscopic data, Supplementary Figs. 1–100 and Tables 1–43.
Supplementary Data 1
Computational details.
Supplementary Data 1
Crystal data for complex A.
Supplementary Data 2
Crystal data for complex B.
Supplementary Data 3
Crystal data for complex C.
Supplementary Data 4
Crystal data for complex D.
Supplementary Data 5
Crystal data for complex 1.
Supplementary Data 6
Crystal data for complex 2.
Supplementary Data 7
Crystal data for complex 3.
Supplementary Data 8
Crystal data for complex 5.
Supplementary Data 9
Crystal data for complex 6.
Supplementary Data 10
Crystal data for complex 7.
Supplementary Data 11
Crystal data for complex 8.
Supplementary Data 12
Crystal data for complex 9.
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Sun, J., Abbenseth, J., Verplancke, H. et al. A platinum(ii) metallonitrene with a triplet ground state. Nat. Chem. 12, 1054–1059 (2020). https://doi.org/10.1038/s41557-020-0522-4
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DOI: https://doi.org/10.1038/s41557-020-0522-4
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