Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Triggering N2 uptake via redox-induced expulsion of coordinated NH3 and N2 silylation at trigonal bipyramidal iron

Nature Chemistry volume 2, pages 558–565 (2010)Cite this article

Subjects

Abstract

The biological reduction of N2 to give NH3 may occur by one of two predominant pathways in which nitrogenous NxHy intermediates, including hydrazine (N2H4), diazene (N2H2), nitride (N3−) and imide (NH2−), may be involved. To test the validity of hypotheses on iron's direct role in the stepwise reduction of N2, model systems for iron are needed. Such systems can test the chemical compatibility of iron with various proposed NxHy intermediates and the reactivity patterns of such species. Here we describe a trigonal bipyramidal Si(o-C6H4PR2)3Fe–L scaffold (R = Ph or i-Pr) in which the apical site is occupied by nitrogenous ligands such as N2, N2H4, NH3 and N2R. The system accommodates terminally bound N2 in the three formal oxidation states (iron(0), +1 and +2). N2 uptake is demonstrated by the displacement of its reduction partners NH3 and N2H4, and N2 functionalizaton is illustrated by electrophilic silylation.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Figure 1: Synthetic scheme for the generation of Fe–N2+, Fe–N2 and Fe–N2− (3, 4b, 5 and 5′).
Figure 2: CV behaviour of (SiPi-Pr3)Fe(N2) (4b).
Figure 3: Solid-state structures of 3, 5 and 5′.
Figure 4: Solid-state structures of {6b}{OTf}, 7a, N2H4B(C6F5)3 and 9b.
Figure 5: Synthesis and characterization of 10 and 11.
Figure 6: Synthesis and characterization of 12.
Figure 7: Zero-field Mössbauer spectra.

Similar content being viewed by others

References

  1. Saouma, C. T., Müller, P. & Peters, J. C. Characterization of structurally unusual diiron NxHy complexes. J. Am. Chem. Soc. 131, 10358–10359 (2009).

    Article  CAS  Google Scholar 

  2. Field, L. D., Li, H. L. & Magill, A. M. Base-mediated conversion of hydrazine to diazene and dinitrogen at an iron center. Inorg. Chem. 48, 5–7 (2009).

    Article  CAS  Google Scholar 

  3. Crossland, J. L., Balesdent, C. G. & Tyler, D. R. Intermediates in the reduction of N2 to NH3: synthesis of iron η2 hydrazido(1-) and diazene complexes. Dalton Trans. 4420–4422 (2009).

  4. Sellmann, D., Shaban, S. Y. & Heinemann, F. W. Syntheses, structures and reactivity of electron-rich Fe and Ru complexes with the new pentadentate ligand Et2NpyS4–H2 {4-(diethylamino)-2,6-bis[(2-mercaptophenyl)thiomethyl]pyridine}. Eur. J. Inorg. Chem. 4591–4601 (2004).

  5. Peters, J. C. & Mehn, M. P. Activation of Small Molecules Ch. 3 (Wiley, 2006).

    Google Scholar 

  6. Barney, B. M. et al. Diazene (HN = NH) is a substrate for nitrogenase: insights into the pathway of N2 reduction. Biochemistry 46, 6784–6794 (2007).

    Article  CAS  Google Scholar 

  7. Barney, B. M. et al. A methyldiazene (HN = N–CH3)-derived species bound to the nitrogenase active-site FeMo cofactor: implications for mechanism. Proc. Natl Acad. Sci. USA 103, 17113–17118 (2006).

    Article  CAS  Google Scholar 

  8. Barney, B. M. et al. Intermediates trapped during nitrogenase reduction of N≡N, CH3−N=NH, and H2N–NH2 . J. Am. Chem. Soc. 127, 14960–14961 (2005).

    Article  CAS  Google Scholar 

  9. Hendrich, M. P. et al. On the feasibility of N2 fixation via a single site FeI/FeIV cycle–spectroscopic studies of FeI(N2)FeI, FeIV≡N, and related species. Proc. Natl Acad. Sci. USA 103, 17107–17112 (2006).

    Article  CAS  Google Scholar 

  10. MacBeth, C. E., Harkins, S. B. & Peters, J. C. Synthesis and characterization of cationic iron complexes supported by the neutral ligands NPi-Pr3, NArPi-Pr3, and NSt-Bu3. Can. J. Chem. 83, 332–340 (2005).

    Article  CAS  Google Scholar 

  11. Hinnemann, B. & Nørskov, J. K., Modeling a central ligand in the nitrogenase FeMo cofactor. J. Am. Chem. Soc. 125, 1466–1467 (2003).

    Article  CAS  Google Scholar 

  12. Mankad, N. P., Whited, M. T. & Peters, J. C. Terminal FeI–N2 and Fe(ii)⋯H–C interactions supported by tris(phosphino)silyl ligands. Angew. Chem. Int. Ed. 46, 5768–5771 (2007).

    Article  CAS  Google Scholar 

  13. Whited, M. T., Mankad, N. P., Lee, Y., Oblad, P. F. & Peters, J. C. Dinitrogen complexes supported by tris(phosphino)silyl ligands. Inorg. Chem. 48, 2507–2517 (2009).

    Article  CAS  Google Scholar 

  14. Bowman, A. C. et al. Synthesis and molecular and electronic structures of reduced bis(imino)pyridine cobalt dinitrogen complexes: ligand versus metal reduction. J. Am. Chem. Soc. 132, 1676–1684 (2010).

    Article  CAS  Google Scholar 

  15. Betley, T. A. & Peters, J. C. Dinitrogen chemistry from trigonally coordinated iron and cobalt platforms. J. Am. Chem. Soc. 125, 10782–10783 (2003).

    Article  CAS  Google Scholar 

  16. Addison, A. W., Rao, T. N., Reedijk, J., van Rijn, J. & Verschoor, G. C. Synthesis, structure and spectroscopic properties of copper(ii) compounds containing nitrogen–sulfur donor ligands; the crystal and molecular structure of aqua[1,7-bis(N-methylbenzimidazol-2′-yl)-2,6-dithiaheptane]copper(ii) perchlorate. J. Chem. Soc. Dalton Trans. 1349–1356 (1984).

  17. Yandulov, D. V. & Schrock, R. R. Studies relevant to catalytic reduction of dinitrogen to ammonia by molybdenum triamidoamine complexes. Inorg. Chem. 44, 1103–1117 (2005).

    Article  CAS  Google Scholar 

  18. Field, L. D., Li, H. L., Dalgarno, S. J. & Turner, P. The first side-on bound metal complex of diazene, HN=NH. Chem. Commun. 1680–1682 (2008).

  19. Crossland, J. L., Zakharov, L. N. & Tyler, D. R. Synthesis and characterization of an iron(ii) η2-hydrazine complex. Inorg. Chem. 46, 10476–10478 (2007).

    Article  CAS  Google Scholar 

  20. Yu, Y., Brennessel, W. W. & Holland, P. L. Borane B–C bond cleavage by a low-coordinate iron hydride complex and N–N bond cleavage by the hydridoborate product. Organometallics 26, 3217–3226 (2007).

    Article  CAS  Google Scholar 

  21. Shakir, M., Parveen, S., Begum, N. & Azim, Y. Interaction of manganese(ii), iron(ii), cobalt(ii), nickel(ii), copper(ii) and zinc(ii) with acetylhydrazine, formed in situ; first crystal structure of tris(acetylhydrazine) nickel(ii) perchlorate. Trans. Metal Chem. 29, 916–920 (2004).

    Article  CAS  Google Scholar 

  22. Albertin, G., Antoniutti, S., Bordignon, E. & Chimisso, F. Preparation of bis(hydrazine) complexes of iron(ii). Inorg. Chem. Commun. 4, 402–404 (2001).

    Article  CAS  Google Scholar 

  23. Sellmann, D., Soglowek, W., Knoch, F., Ritter, G. & Dengler, J. Transition-metal complexes with sulfur ligands. 88. Dependence of spin state, structure, and reactivity of [Fe(ii)(L)(‘NHS4’)] complexes on the coligand L (L = CO, N2H2, N2H4, NH3, pyridine, NHCH3NH2, CH3OH, THF, P(OCH3)3, P(OPh)3): model complexes for iron nitrogenases (‘N2H4’2− = dianion of 2,2′-bis[(2-mercaptophenyl)thio]diethylamine). Inorg. Chem. 31, 3711–3717 (1992).

    Article  CAS  Google Scholar 

  24. Casey, M. T. et al. Reaction of 1,1′-diacetylferrocene with hydrazine hydrate: synthesis and X-ray crystal structures of bis(hydrazine)bis(hydrazinecarboxylato-N′,O)iron(ii), [Fe(N2H4)2(O2CNHNH2)2], and the cyclic biferrocene diazine, [—N(Me)CC5H4FeC5H4C(Me)N—]2 . Polyhedron 10, 483–489 (1991).

    Article  CAS  Google Scholar 

  25. Goedken, V. L., Peng, S.-M., Molin-Norris, J. & Park, Y.-A. Carbon monoxide complexes of iron(ii): synthesis and structural studies of five- and six-coordinate complexes of the macrocyclic ligand, C22H22N42−. J. Am. Chem. Soc. 98, 8391–8400 (1976).

    Article  CAS  Google Scholar 

  26. Davies, S. C. et al. Vanadium complexes of the N(CH2CH2S)33− and O(CH2CH2S)22− ligands with coligands relevant to nitrogen fixation processes. Inorg. Chem. 39, 3485–3498 (2000).

    Article  CAS  Google Scholar 

  27. Alhomaidan, O., Hollink, E. & Stephan, D. W. Main group heterocycles from lithiated phosphinimines. Organometallics 26, 3041–3048 (2007).

    Article  CAS  Google Scholar 

  28. Aguilar, D., Contel, M., Navarro, R. & Urriolabeitia, E. P. Organogold(ii) iminophosphorane complexes as efficient catalysts in the addition of 2-methylfuran and electron-rich arenes to methyl vinyl ketone. Organometallics 26, 4604–4611 (2007).

    Article  CAS  Google Scholar 

  29. Bielsa, R., Larrea, A., Navarro, R., Soler, T. & Urriolabeitia, E. P. Synthesis, structure, reactivity, and catalytic activity of C,N- and C,N,N-orthopalladated iminophosphoranes. Eur. J. Inorg. Chem. 1724–1736 (2005).

  30. Chan, K. T. K. et al. Anionic phosphinimine-chelate complexes of rhodium and iridium: steric and electronic influences on oxidative addition of CH2Cl2 . Organometallics 23, 381–390 (2004).

    Article  CAS  Google Scholar 

  31. Spencer, L. P. et al. Pyridine– and imidazole–phosphinimine bidentate ligand complexes: considerations for ethylene oligomerization catalysts. Organometallics 22, 3841–3854 (2003).

    Article  CAS  Google Scholar 

  32. LePichon, L., Stephan, D. W., Gao, Z. & Wang, Q. Iron phosphinimide and phosphinimine complexes: catalyst precursors for ethylene polymerization. Organometallics 21, 1362–1366 (2002).

    Article  CAS  Google Scholar 

  33. Mountford, A. J. et al. Intra- and intermolecular N–H · · · F–C hydrogen-bonding interactions in amine adducts of tris(pentafluorophenyl)borane and -alane. Inorg. Chem. 44, 5921–5933 (2005).

    Article  CAS  Google Scholar 

  34. Hyla-Kryspin, I., Haufe, G. & Grimme, S. Weak hydrogen bridges: a systematic theoretical study on the nature and strength of C–H⋯F–C interactions. Chem. Eur. J. 10, 3411–3422 (2004).

    Article  CAS  Google Scholar 

  35. Brammer, L., Bruton, E. A. & Sherwood, P. Understanding the behavior of halogens as hydrogen bond acceptors. Cryst. Growth Des. 1, 277–290 (2001).

    Article  CAS  Google Scholar 

  36. Takemura, H. et al. The C–F · · · cation interaction: an ammonium complex of a hexafluoro macrocyclic cage compound. Chem. Eur. J. 6, 2334 (2000).

    Article  CAS  Google Scholar 

  37. Howard, J. A. K., Hoy, V. J., O'Hagan, D. & Smith, G. T. How good is fluorine as a hydrogen bond acceptor? Tetrahedron 52, 12613–12622 (1996).

    Article  CAS  Google Scholar 

  38. Davies, S. C., Hughes, D. L., Richards, R. L. & Sanders, J. R. Molybdenum and tungsten complexes of the N(CH2CH2S)33− (NS3) ligand with oxide, sulfide, diazenide, hydrazide and nitrosyl co-ligands. J. Chem. Soc. Dalton Trans. 719–725 (2000).

  39. Albertin, G. et al. Reactivity of hydrides FeH2(CO)2P2 (P = phosphites) with aryldiazonium cations: preparation, characterization, X-ray crystal structure, and electrochemical studies of mono- and binuclear aryldiazenido complexes. Inorg. Chem. 37, 5602–5610 (1998).

    Article  CAS  Google Scholar 

  40. Albertin, G., Antoniutti, S., Pelizzi, G., Vitali, F. & Bordignon, E. Bis(aryldiazene) derivatives of iron(ii): preparation, characterization, and properties of the first complexes containing two diazene ligands bonded to the same central metal. The X-ray crystal structures of hexacoordinate [FeH(4-CH3C6H4NNH)[P(OEt)3]4]+, and pentacoordinate [Fe(4-CH3C6H4N2)[P(OEt)3]4]+ cations. J. Am. Chem. Soc. 108, 6627–6634 (1986).

    Article  CAS  Google Scholar 

  41. Haymore, B. L. & Ibers, J. A. Aryldiazo complexes. Structure of an iron–aryldiazo complex, dicarbonyl bis(triphenylphosphine) benzenediazonium iron(1+) tetrafluoroborate (1–). Inorg. Chem. 14, 1369–1376 (1975).

    Article  CAS  Google Scholar 

  42. Yandulov, D. V. & Schrock, R. R. Reduction of dinitrogen to ammonia at a well-protected reaction site in a molybdenum triamidoamine complex. J. Am. Chem. Soc. 124, 6252–6253 (2002).

    Article  CAS  Google Scholar 

Download references

Acknowledgements

We acknowledge the National Institutes of Health (GM-070757). Funding for the Massechussetts Institute of Technology Department of Chemistry Instrumentation Facility was provided in part by the National Science Foundation (NSF) (CHE-0234877). P. Mueller provided assistance with XRD analyses. N.P.M. received an NSF graduate fellowship. We thank R.H. Holm and T.A. Betley at Harvard University for providing us with access to a Mössbauer spectrometer.

Author information

Author notes

  1. Jonas C. Peters

    Present address: Present address: Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA,

Authors and Affiliations

  1. Department of Chemistry, Massachusetts Institute of Technology, Cambridge, 02139, MA, USA

    Yunho Lee, Neal P. Mankad & Jonas C. Peters

Authors
  1. Yunho Lee
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Neal P. Mankad
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Jonas C. Peters
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

Y.L., N.P.M. and J.C.P. conceived and designed the experiments, Y.L. and N.P.M. performed the experiments and Y.L. and J.C.P. co-wrote the paper.

Corresponding author

Correspondence to Jonas C. Peters.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary information

Supplementary information (PDF 9061 kb)

Supplementary information

Crystallographic information for compound 1a (CIF 25 kb)

Supplementary information

Crystallographic information for compound 1b (CIF 22 kb)

Supplementary information

Crystallographic information for compound 3 (CIF 37 kb)

Supplementary information

Crystallographic information for compound 4b (CIF 23 kb)

Supplementary information

Crystallographic information for compound 5 (CIF 16 kb)

Supplementary information

Crystallographic information for compound 5′ (CIF 46 kb)

Supplementary information

Crystallographic information for compound 6a·BArF (CIF 75 kb)

Supplementary information

Crystallographic information for compound 6a·OTf (CIF 49 kb)

Supplementary information

Crystallographic information for compound 6b·OTf (CIF 25 kb)

Supplementary information

Crystallographic information for compound 7a (CIF 46 kb)

Supplementary information

Crystallographic information for compound 7b (CIF 65 kb)

Supplementary information

Crystallographic information for compound 8 (CIF 31 kb)

Supplementary information

Crystallographic information for compound 9a (CIF 34 kb)

Supplementary information

Crystallographic information for compound 9b (CIF 35 kb)

Supplementary information

Crystallographic information for compound 10 (CIF 23 kb)

Supplementary information

Crystallographic information for compound 11 (CIF 43 kb)

Supplementary information

Crystallographic information for compound 12 (CIF 20 kb)

Rights and permissions

Reprints and permissions

About this article

Cite this article

Lee, Y., Mankad, N. & Peters, J. Triggering N2 uptake via redox-induced expulsion of coordinated NH3 and N2 silylation at trigonal bipyramidal iron. Nature Chem 2, 558–565 (2010). https://doi.org/10.1038/nchem.660

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nchem.660

This article is cited by

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing