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.

Oligomeric ferrocene rings

Abstract

Cyclic oligomers comprising strongly interacting redox-active monomer units represent an unknown, yet highly desirable class of nanoscale materials. Here we describe the synthesis and properties of the first family of molecules belonging to this compound category—differently sized rings comprising only 1,1′-disubstituted ferrocene units (cyclo[n], n = 5–7, 9). Due to the close proximity and connectivity of centres (covalent Cp–Cp linkages; Cp = cyclopentadienyl) solution voltammograms exhibit well-resolved, separated 1e waves. Theoretical interrogations into correlations based on ring size and charge state are facilitated using values of the equilibrium potentials of these transitions, as well as their relative spacing. As the interaction free energies between the redox centres scale linearly with overall ring charge and in conjunction with fast intramolecular electron transfer (107 s−1), these molecules can be considered as uniformly charged nanorings (diameter 1–2 nm).

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Figure 1: Synthesis and structure of oligomeric ferrocene rings.
Figure 2: 1H NMR spectroscopy of ferrocene rings (n = 2, 5–7, 9).
Figure 3: Solution electrochemistry for ferrocene rings.
Figure 4: Solution voltammetry correlations for different ring sizes.

References

  1. 1

    Francl, M. A. Molecule with a ring to it. Nature Chem. 7, 6–7 (2015).

    Article  CAS  Google Scholar 

  2. 2

    Steed, J. W. & Atwood, J. L. Supramolecular Chemistry 2nd edn (Wiley-Blackwell, 2009).

    Book  Google Scholar 

  3. 3

    Grossmann, B. et al. Seven doubly bridged ferrocene units in a cycle. Angew. Chem. Int. Ed. Engl. 36, 387–389 (1997).

    Article  CAS  Google Scholar 

  4. 4

    Herbert, D. E. et al. Redox-active metallomacrocycles and cyclic metallopolymers: photocontrolled ring-opening oligomerization and polymerization of silicon-bridged [1]ferrocenophanes using substitutionally-labile Lewis bases as initiators. J. Am. Chem. Soc. 131, 14958–14968 (2009).

    Article  CAS  PubMed  Google Scholar 

  5. 5

    Xu, L., Wang, Y. X., Chen, L. J. & Yang, H. B. Construction of multiferrocenyl metallacycles and metallacages via coordination-driven self-assembly: from structure to functions. Chem. Soc. Rev. 44, 2148–2167 (2015).

    Article  CAS  PubMed  Google Scholar 

  6. 6

    Arduini, A. et al. Solvent- and light-controlled unidirectional transit of a nonsymmetric molecular axle through a nonsymmetric molecular wheel. Chem. Eur. J. 18, 16203–16213 (2012).

    Article  CAS  PubMed  Google Scholar 

  7. 7

    Kano, S., Tada, T. & Majima, Y. Nanoparticle characterization based on STM and STS. Chem. Soc. Rev. 44, 970–987 (2015).

    Article  CAS  PubMed  Google Scholar 

  8. 8

    Stark, W. J., Stoessel, P. R., Wohlleben, W. & Hafner, A. Industrial applications of nanoparticles. Chem. Soc. Rev. 44, 5793–5805 (2015).

    Article  CAS  PubMed  Google Scholar 

  9. 9

    Albrecht, T. Electrochemical tunnelling sensors and their potential applications. Nature Commun. 3, 829 (2012).

    Article  CAS  Google Scholar 

  10. 10

    Albrecht, T., Mertens, S. F. L. & Ulstrup, J. Intrinsic multistate switching of gold clusters through electrochemical gating. J. Am. Chem. Soc. 129, 9162–9167 (2007).

    Article  CAS  PubMed  Google Scholar 

  11. 11

    Kealy, T. J. & Pauson, P. L. A new type of organo-iron compound. Nature 168, 1039–1040 (1951).

    Article  CAS  Google Scholar 

  12. 12

    Miller, S. A., Tebboth, J. A. & Tremaine, J. F. Dicyclopentadienyliron. J. Chem. Soc. 632–635 (1952).

  13. 13

    Rausch, M. D., Fischer, E. O. & Grubert, H. The aromatic reactivity of ferrocene, ruthenocene and osmocene. J. Am. Chem. Soc. 82, 76–82 (1960).

    Article  CAS  Google Scholar 

  14. 14

    Long, N. J. Metallocenes: Introduction to Sandwich Complexes (Wiley-Blackwell, 1997).

    Google Scholar 

  15. 15

    Watts, W. E. The [1,1]ferrocenophane system. J. Am. Chem. Soc. 88, 855–856 (1966).

    Article  CAS  Google Scholar 

  16. 16

    Katz, T. J., Acton, N. & Martin, G. [1n]ferrocenophanes. J. Am. Chem. Soc. 91, 2804–2805 (1969).

    Article  CAS  Google Scholar 

  17. 17

    Mueller-Westerhoff, U. T. & Swiegers, G. F. A synthesis of the cyclic ferrocene tetramer [1]4ferrocenophane. Chem. Lett. 23, 67–68 (1994).

    Article  Google Scholar 

  18. 18

    Perevalova, E. G. & Nesmeyanova, O. A. Preparation of biferrocenyl by the Ullmann reaction. Dokl. Akad. Nauk 130, 1093–1094 (1960).

    Google Scholar 

  19. 19

    Rausch, M. D., Roling, P. V. & Siegel, A. Formation of ferrocene oligomers from mixed Ullmann reactions of halogenoferrocenes. J. Chem. Soc. D 502–503 (1970).

  20. 20

    Roling, P. V. & Rausch, M. D. Formation of 1,1′-oligomeric ferrocenes from mixed Ullmann reactions of haloferrocenes. J. Org. Chem. 37, 729–732 (1972).

    Article  CAS  Google Scholar 

  21. 21

    Neuse, E. W. & Loonat, M. S. Synthesis of ferrocenylruthenocene. Transition Metal Chem. 6, 260–263 (1981).

    Article  CAS  Google Scholar 

  22. 22

    Goeltz, J. C. & Kubiak, C. P. Facile purification of iodoferrocene. Organometallics 30, 3908–3910 (2011).

    Article  CAS  Google Scholar 

  23. 23

    Roling, P. V. & Rausch, M. D. Formation of 1,2-oligomeric ferrocenes from Ullmann reactions of iodoferrocenes. J. Org. Chem. 141, 195–204 (1977).

    Article  CAS  Google Scholar 

  24. 24

    Izumi, T. & Kasahara, A. The formation of 1,1′-oligomeric ferrocenes from chloromercuriferrocene and bis(chloromercuri)ferrocene. Bull. Chem. Soc. Jpn 48, 1955–1956 (1975).

    Article  CAS  Google Scholar 

  25. 25

    Bomparola, R., Davies, R. P., Gray, T. & White, A. J. P. Structures of lithium ferrocenylenecuprates and their oxidative coupling reactions. Organometallics 28, 4632–4635 (2009).

    Article  CAS  Google Scholar 

  26. 26

    Nishihara, H., Hirao, T., Aramaki, K. & Aoki, K. Redox properties of hepta(1,1′-dihexylferrocenylene). Synth. Met. 84, 935–936 (1997).

    Article  CAS  Google Scholar 

  27. 27

    Bednarik, L. & Neuse, E. W. Oligonuclear ruthenocene complexes. J. Am. Chem. Soc. 45, 2032–2033 (1980).

    CAS  Google Scholar 

  28. 28

    Ingram, G., Jaitner, P. & Schwarzhans, K. E. Synthesis and characterization of hetero-oligometallocenes containing ruthenocene and osmocene. Z. Naturforsch. B 45, 781–784 (1990).

    Article  CAS  Google Scholar 

  29. 29

    Andre, M. et al. Synthesis and preparative HPLC-separation of heteronuclear oligometallocenes. Isolation of cations of rhodocenylferrocene, 1,1′-dirhodocenylferrocene, and 1-cobaltocenyl-,1′-rhodocenylferrocene. Chromatographia 30, 543–545 (1990).

    Article  CAS  Google Scholar 

  30. 30

    Schottenberger, H., Ingram, G., Obendorf, D. & Tessadri, R. Ferrocene-substituted nickelocenes via ferrocenylcyclopentadienides. Synlett 905–907 (1991).

  31. 31

    Breuer, R. & Schmittel, M. 1,1′-Biferrocenylenes—the more redox stable ferrocenes! New derivatives, corrected NMR assignments, redox behavior, and spectroelectrochemistry. Organometallics 31, 1870–1878 (2012).

    Article  CAS  Google Scholar 

  32. 32

    LeVanda, C. et al. Bis(fulvalene)diiron, its mono- and dications. Intramolecular exchange interactions in a rigid system. J. Am. Chem. Soc. 98, 3181–3187 (1976).

    Article  CAS  Google Scholar 

  33. 33

    Shekurov, R. P. et al. Synthesis and structure of ferrocenylphosphinic acids. J. Org. Chem. 766, 40–48 (2014).

    Article  CAS  Google Scholar 

  34. 34

    Shekurov, R., Miluykov, V., Kataeva, O., Tufatullin, A. & Sinyashin, O. Crystal structure of cyclic tris(ferrocene-1,1′-diyl). Acta Crystallogr. E 70, m318–m319 (2014).

    Article  CAS  Google Scholar 

  35. 35

    Santi, S. et al. Synthesis of the prototypical cyclic metallocene triad: mixed-valence properties of [(FeCp)3(trindenyl)] isomers. Angew. Chem. Int. Ed. 47, 5331–5334 (2008).

    Article  CAS  Google Scholar 

  36. 36

    Katz, T. J. & Slusarek, W. The trindene trianion. J. Am. Chem. Soc. 102, 1058–1063 (1980).

    Article  CAS  Google Scholar 

  37. 37

    Zhang, S., Zhang, D. & Liebeskind, L. S. Ambient temperature, Ullmann-like reductive coupling of aryl, heteroaryl, and alkenyl halides. J. Org. Chem. 62, 2312–2313 (1997).

    Article  CAS  PubMed  Google Scholar 

  38. 38

    Babudri, F., Cardone, A., Farinola, G. M. & Naso, F. A versatile copper-induced synthesis of fluorinated oligo(para-phenylenes). Tetrahedron 54, 14609–14616 (1998).

    Article  CAS  Google Scholar 

  39. 39

    John, D. E. et al. New bi(tetrathiafulvalenyl) derivatives and their radical cations: synthetic and X-ray structural studies. J. Mater. Chem. 10, 1273–1279 (2000).

    Article  CAS  Google Scholar 

  40. 40

    Zonta, C., Fabris, F. & De Lucchi, O. The pyrrole approach toward the synthesis of fully functionalized cup-shaped molecules. Org. Lett. 7, 1003–1006 (2005).

    Article  CAS  PubMed  Google Scholar 

  41. 41

    Fabris, F., Zonta, C., Borsato, G. & De Lucchi, O. Benzocyclotrimers: from the Mills−Nixon effect to gas hosting. Acc. Chem. Res. 44, 416–423 (2011).

    Article  CAS  PubMed  Google Scholar 

  42. 42

    Inkpen, M. S., Du, S. Driver, M., Albrecht, T. & Long, N. J. Oxidative purification of halogenated ferrocenes. Dalton Trans. 42, 2813–2816 (2013).

    Article  CAS  PubMed  Google Scholar 

  43. 43

    Barrière, F. & Geiger, W. E. Use of weakly coordinating anions to develop an integrated approach to the tuning of ΔE1/2 values by medium effects. J. Am. Chem. Soc. 128, 3980–3989 (2006).

    Article  CAS  PubMed  Google Scholar 

  44. 44

    Camire, N., Mueller-Westerhoff, U. T. & Geiger, W. E. Improved electrochemistry of multi-ferrocenyl compounds: investigation of biferrocene, terferrocene, bis(fulvalene)diiron and diferrocenylethane in dichloromethane using [NBu4][B(C6F5)4] as supporting electrolyte. J. Org. Chem. 637–639, 823–826 (2001).

    Article  Google Scholar 

  45. 45

    Bard, A. J. & Faulkner, L. Y. Electrochemical Methods 2nd edn (Wiley, 2004).

    Google Scholar 

  46. 46

    Richardson, D. E. & Taube, H. Mixed-valence molecules: electronic delocalization and stabilization. Coord. Chem. Rev. 60, 107–129 (1984).

    Article  CAS  Google Scholar 

  47. 47

    Sokol, W. F., Evans, D. H., Niki, K. & Yagi, T. Reversible voltammetric response for a molecule containing four non-equivalent redox sites with application to cytochrome c3 of Desulfovibrio vulgaris, strain Miyazaki. J. Electroanal. Chem. Interfacial Electrochem. 108, 107–115 (1980).

    Article  CAS  Google Scholar 

  48. 48

    Masuda, Y. & Shimizu, C. Solvent effect on intramolecular electron transfer rates of mixed-valence biferrocene monocation derivatives. J. Phys. Chem. A 110, 7019–7027 (2006).

    Article  CAS  PubMed  Google Scholar 

  49. 49

    Brown, G. M. et al. Oxidation-state and electron-transfer properties of mixed-valence 1,1′-polyferrocene ions. Inorg. Chem. 14, 506–511 (1975).

    Article  CAS  Google Scholar 

  50. 50

    Ohanian, H. C. & Markert, J. T. Physics for Engineers and Scientists 3rd edn (W.W. Norton & Company, 2007).

    Google Scholar 

Download references

Acknowledgements

M.S.I., T.A. and N.J.L. acknowledge the Leverhulme Trust (RPG 2012-754) for funding. The authors are grateful to the referees for useful comments and suggestions concerning the extent of charge delocalization in these materials.

Author information

Affiliations

Authors

Contributions

M.S.I., T.A. and N.J.L. conceived the work and designed the experiments. M.S.I. synthesized the materials and performed the solution electrochemical measurements. A.J.P.W. performed the X-ray crystallographic experiments. S.S., M.L. and R.F.W. performed the UV/vis/NIR spectroscopy experiments. All authors contributed to writing the paper.

Corresponding authors

Correspondence to Tim Albrecht or Nicholas J. Long.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary information

Supplementary information (PDF 2179 kb)

Supplementary information

Crystallographic data for compound cyclo[6]-benzene (CIF 362 kb)

Supplementary information

Crystallographic data for compound cyclo[6]-toluene (CIF 305 kb)

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Inkpen, M., Scheerer, S., Linseis, M. et al. Oligomeric ferrocene rings. Nature Chem 8, 825–830 (2016). https://doi.org/10.1038/nchem.2553

Download citation

Further reading

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