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Stabilization of anti-aromatic and strained five-membered rings with a transition metal

Nature Chemistry volume 5, pages 698–703 (2013)Cite this article

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Abstract

Anti-aromatic compounds, as well as small cyclic alkynes or carbynes, are particularly challenging synthetic goals. The combination of their destabilizing features hinders attempts to prepare molecules such as pentalyne, an 8π-electron anti-aromatic bicycle with extremely high ring strain. Here we describe the facile synthesis of osmapentalyne derivatives that are thermally viable, despite containing the smallest angles observed so far at a carbyne carbon. The compounds are characterized using X-ray crystallography, and their computed energies and magnetic properties reveal aromatic character. Hence, the incorporation of the osmium centre not only reduces the ring strain of the parent pentalyne, but also converts its Hückel anti-aromaticity into Craig-type Möbius aromaticity in the metallapentalynes. The concept of aromaticity is thus extended to five-membered rings containing a metal–carbon triple bond. Moreover, these metal–aromatic compounds exhibit unusual optical effects such as near-infrared photoluminescence with particularly large Stokes shifts, long lifetimes and aggregation enhancement.

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Figure 1: Synthesis, structure and reactivity of osmapentalynes.
Figure 2: Aromaticity in osmapentalynes: downfield 1H chemical shifts and resonance structures.
Figure 3: NICS(0)zzcontributions of the four key occupied perimeter molecular orbitals of model complex 2′.
Figure 4: ISE evaluations of the anti-aromaticity of pentalene and pentalyne and the aromaticity of osmapentalyne models.
Figure 5: Photoluminescence of osmapentalyne 2a.

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References

  1. Minkin, V. I., Glukhovtsev, M. N. & Simkin, B. Y. Aromaticity and Antiaromaticity: Electronic and Structural Aspects (Wiley, 1994).

    Google Scholar 

  2. De Proft, F. & Geerlings, P. Conceptual and computational DFT in the study of aromaticity. Chem. Rev. 101, 1451–1464 (2001).

    Article  CAS  PubMed  Google Scholar 

  3. Cyranski, M. K. Energetic aspects of cyclic pi-electron delocalization: evaluation of the methods of estimating aromatic stabilization energies. Chem. Rev. 105, 3773–3811 (2005).

    Article  CAS  PubMed  Google Scholar 

  4. Thorn, D. L. & Hoffmann, R. Delocalization in metallocycles. Nouv. J. Chim. 3, 39–45 (1979).

    CAS  Google Scholar 

  5. Elliott, G. P., Roper, W. R. & Waters, J. M. Metallacyclohexatrienes or ‘metallabenzenes.’ Synthesis of osmabenzene derivatives and X-ray crystal structure of [Os(CSCHCHCHCH)(CO)(PPh3)2]. J. Chem. Soc. Chem. Commun. 811–813 (1982).

  6. Hückel, E. Quantum-theoretical contributions to the benzene problem. I. The electron configuration of benzene and related compounds. Z. Phys. 70, 204–286 (1931).

    Article  Google Scholar 

  7. Craig, D. P. & Paddock, N. L. A novel type of aromaticity. Nature 181, 1052–1053 (1958).

    Article  CAS  Google Scholar 

  8. Heilbronner, E. Hückel molecular orbitals of Möbius-type conformations of annulenes. Tetrahedron Lett. 29, 1923–1928 (1964).

    Article  Google Scholar 

  9. Rzepa, H. S. Möbius aromaticity and delocalization. Chem. Rev. 105, 3697–3715 (2005).

    Article  CAS  PubMed  Google Scholar 

  10. Mauksch, M., Gogonea, V., Jiao, H. & Schleyer, P. v. R. Monocyclic (CH)9 +— a Heilbronner Möbius aromatic system revealed. Angew. Chem. Int. Ed. 37, 2395–2397 (1998).

    Article  CAS  Google Scholar 

  11. Wiberg, K. B. Antiaromaticity in monocyclic conjugated carbon rings. Chem. Rev. 101, 1317–1331 (2001).

    Article  CAS  PubMed  Google Scholar 

  12. Gleiter, R. & Merger, R. in Modern Acetylene Chemistry (eds Stang, P. J. & Diederich, F.) Ch. 8 (VCH, 1995).

    Google Scholar 

  13. Wittig, G. Small rings with carbon–carbon triple bonds. Angew. Chem. Int. Ed. Engl. 1, 415–419 (1962).

    Article  Google Scholar 

  14. Montgomery, L. K., Scardiglia, F. & Roberts, J. D. Evidence for cyclohexyne and cyclopentyne as intermediates in the coupling reactions of phenyllithium with 1-chlorocyclohexene and 1-chlorocyclopentene. J. Am. Chem. Soc. 87, 1917–1925 (1965).

    Article  CAS  Google Scholar 

  15. Krebs, A. & Kimling, H. 3,3,7,7-Tetramethylcycloheptyne, an isolable seven-membered carbocyclic alkyne. Angew. Chem. Int. Ed. Engl. 10, 509–510 (1971).

    Article  CAS  Google Scholar 

  16. Chapman, O. L. et al. Photochemical transformations. LII. Benzyne. J. Am. Chem. Soc. 95, 6134–6135 (1973).

    Article  CAS  Google Scholar 

  17. Chapman, O. L., Gano, J., West, P. R., Regitz, M. & Maas, G. Acenaphthyne. J. Am. Chem. Soc. 103, 7033–7036 (1981).

    Article  CAS  Google Scholar 

  18. Krebs, A. & Wilke, J. Angle strained cycloalkynes. Top. Curr. Chem. 109, 189–233 (1983).

    Article  CAS  Google Scholar 

  19. Suzuki, N., Nishiura, M. & Wakatsuki, Y. Isolation and structural characterization of 1-zirconacyclopent-3-yne, five-membered cyclic alkynes. Science 295, 660–663 (2002).

    Article  CAS  PubMed  Google Scholar 

  20. Suzuki, N., Hashizume, D., Koshino, H. & Chihara, T. Transformation of a 1-zirconacyclopent-3-yne, a five-membered cycloalkyne, into a 1-zirconacyclopent-3-ene and formal ‘1-zirconacyclopenta-2,3-dienes’. Angew. Chem. Int. Ed. 47, 5198–5202 (2008).

    Article  CAS  Google Scholar 

  21. Suzuki, N. & Hashizume, D. Five-membered metallacycloalkynes formed from group 4 metals and [n]cumulene (n = 3,5) ligands. Coord. Chem. Rev. 254, 1307–1326 (2010).

    Article  CAS  Google Scholar 

  22. Suzuki, N. et al. Characterization of the E isomer of tetrasubstituted [5]cumulene and trapping of the Z isomer as a zirconocene complex. Organometallics 30, 3544–3548 (2011).

    Article  CAS  Google Scholar 

  23. Wen, T. B., Zhou, Z. Y. & Jia, G. Synthesis and characterization of a metallabenzyne. Angew. Chem. Int. Ed. 40, 1951–1954 (2001).

    Article  CAS  Google Scholar 

  24. Jia, G. Progress in the chemistry of metallabenzynes. Acc. Chem. Res. 37, 479–486 (2004).

    Article  CAS  PubMed  Google Scholar 

  25. Jia, G. Recent progress in the chemistry of osmium carbyne and metallabenzyne complexes. Coord. Chem. Rev. 251, 2167–2187 (2007).

    Article  CAS  Google Scholar 

  26. He, G. et al. A metallanaphthalyne complex from zinc reduction of a vinylcarbyne complex. Angew. Chem. Int. Ed. 46, 9065–9068 (2007).

    Article  CAS  Google Scholar 

  27. Liu, B. et al. Selective synthesis of osmanaphthalene and osmanaphthalyne by intramolecular C–H activation. Angew. Chem. Int. Ed. 48, 5461–5464 (2009).

    Article  CAS  Google Scholar 

  28. Jones, W. M. & Klosin, J. Transition-metal complexes of arynes, strained cyclic alkynes, and strained cyclic cumulenes. Adv. Organomet. Chem. 42, 147–221 (1998).

    Article  CAS  Google Scholar 

  29. Rosenthal, U. Stable cyclopentynes—made by metals!? Angew. Chem. Int. Ed. 43, 3882–3887 (2004).

    Article  CAS  Google Scholar 

  30. Lamač, M. et al. Formation of a 1-zircona-2,5-disilacyclopent-3-yne: coordination of 1,4-disilabutatriene to zirconocene? Angew. Chem. Int. Ed. 49, 2937–2940 (2010).

    Article  CAS  Google Scholar 

  31. Jemmis, E. D., Phukan, A. K., Jiao, H. & Rosenthal, U. Structure and neutral homoaromaticity of metallacyclopentene, -pentadiene, -pentyne, and -pentatriene: a density functional study. Organometallics 22, 4958–4965 (2003).

    Article  CAS  Google Scholar 

  32. Xia, H. et al. Osmabenzenes from the reactions of HC≡CCH(OH)C≡CH with OsX2(PPh3)3 (X = Cl, Br). J. Am. Chem. Soc. 126, 6862–6863 (2004).

    Article  CAS  PubMed  Google Scholar 

  33. Ugolotti, J. et al. Five-membered metallacyclic allenoids: synthesis and structure of remarkably stable strongly distorted cyclic allene derivatives. Angew. Chem. Int. Ed. 47, 2622–2625 (2008).

    Article  CAS  Google Scholar 

  34. Rosenthal, U. et al. Synthesis and structure of the smallest cyclic cumulene; reaction of 1,3-diynes with zirconocene complexes. Angew. Chem. Int. Ed. Engl. 33, 1605–1607 (1994).

    Article  Google Scholar 

  35. Rosenthal, U., Burlakov, V. V., Arndt, P., Baumann, W. & Spannenberg, A. Five-membered titana- and zirconacyclocumulenes: stable 1-metallacyclopenta-2,3,4-trienes. Organometallics 24, 456–471 (2005).

    Article  CAS  Google Scholar 

  36. Luecke, H. F. & Bergman, R. G. Synthesis, structural characterization, and chemistry of a monomeric cationic iridium carbyne complex. J. Am. Chem. Soc. 120, 11008–11009 (1998).

    Article  CAS  Google Scholar 

  37. Frisch, M. J. et al. Gaussian 03, Revision E.01 (Gaussian, 2004).

    Google Scholar 

  38. Ng, S. M., Huang, X., Wen, T. B., Jia, G. & Lin, Z. Theoretical studies on the stabilities of metallabenzynes. Organometallics 22, 3898–3904 (2003).

    Article  CAS  Google Scholar 

  39. Schleyer, P. v. R., Maerker, C., Dransfeld, A., Jiao, H. & Hommes, N. J. R. v. E. Nucleus-independent chemical shifts: a simple and efficient aromaticity probe. J. Am. Chem. Soc. 118, 6317–6318 (1996).

    Article  CAS  PubMed  Google Scholar 

  40. Jiao, H., Schleyer, P. v. R., Mo, Y., McAllister, M. A. & Tidwell, T. T. Magnetic evidence for the aromaticity and antiaromaticity of charged fluorenyl, indenyl, and cyclopentadienyl systems. J. Am. Chem. Soc. 119, 7075–7083 (1997).

    Article  CAS  Google Scholar 

  41. Chen, Z., Wannere, C. S., Corminboeuf, C., Puchta, R. & Schleyer, P. v. R. Nucleus-independent chemical shifts (NICS) as an aromaticity criterion. Chem. Rev. 105, 3842–3888 (2005).

    Article  CAS  PubMed  Google Scholar 

  42. Fallah-Bagher-Shaidaei, H., Wannere, C. S., Corminboeuf, C., Puchta, R. & Schleyer, P. v. R. Which NICS aromaticity index for planar π rings is best? Org. Lett. 8, 863–866 (2006).

    Article  CAS  PubMed  Google Scholar 

  43. Glendening, E. D. et al. NBO 5.0 (Theoretical Chemistry Institute, University of Wisconsin, 2001).

  44. Schleyer, P. v. R. & Pühlhofer, F. Recommendations for the evaluation of aromatic stabilization energies. Org. Lett. 4, 2873–2876 (2002).

    Article  CAS  PubMed  Google Scholar 

  45. Wannere, C. S. et al. On the stability of large [4n]annulenes. Org. Lett. 5, 2983–2986 (2003).

    Article  CAS  PubMed  Google Scholar 

  46. Lakowicz, J. R. Principles of Fluorescence Spectroscopy 3rd edn (Springer, 2006).

    Book  Google Scholar 

  47. Moore, E. G., Samuel, A. P. S. & Raymond, K. N. From antenna to assay: lessons learned in lanthanide luminescence. Acc. Chem. Res. 42, 542–552 (2009).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  48. Escobedo, J. O., Rusin, O., Lim, S. & Strongin, R. M. NIR dyes for bioimaging applications. Curr. Opin. Chem. Biol. 14, 64–70 (2010).

    Article  CAS  PubMed  Google Scholar 

  49. Hong, Y., Lam, J. W. Y. & Tang, B. Z. Aggregation-induced emission. Chem. Soc. Rev. 40, 5361–5388 (2011).

    Article  CAS  PubMed  Google Scholar 

  50. Mauksch, M. & Tsogoeva, S. B. Demonstration of “Möbius” Aromaticity in Planar Metallacycles. Chem. Eur. J. 16, 7843–7851 (2010).

    Article  CAS  PubMed  Google Scholar 

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Acknowledgements

This research was supported by the National Science Foundation of China (grant nos. 20925208, 21172184, 21175113 and 21273177), the National Basic Research Program of China (nos. 2012CB821600 and 2011CB808504), the Program for Changjiang Scholars and Innovative Research Team in University of China, and US-NSF Grant CHE 105-7466. The authors thank E. Meggers at Philipps-Universität Marburg, Zhenyang Lin at the Hong Kong University of Science and Technology, Yirong Mo at Western Michigan University, and Xinzheng Yang at the University of California, Berkeley, for their suggestions, and, in particular J. I-Chia Wu, Georgia, for instructive discussions and her assistance with aromaticity analyses.

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Authors and Affiliations

  1. State Key Laboratory of Physical Chemistry of Solid Surfaces and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China

    Congqing Zhu, Shunhua Li, Ming Luo, Xiaoxi Zhou, Yufen Niu, Jun Zhu, Zexing Cao, Xin Lu, Tingbin Wen, Zhaoxiong Xie & Haiping Xia

  2. Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, Xiamen University, Xiamen, 361005, China

    Minglian Lin, Jun Zhu, Zexing Cao & Xin Lu

  3. Department of Chemistry, University of Georgia, Athens, 30602, Georgia, USA

    Paul v. R. Schleyer

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  1. Congqing Zhu
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Contributions

H.X. conceived the project. C.Z., M.L. and X.Z. performed the experiments. S.L. and Y.N. conducted the luminescence study of osmapentalynes. C.Z. and T.W. recorded all NMR data and solved all X-ray structures. H.X., C.Z. and T.W. analysed the experimental data. J.Z. conceived the theoretical work and, with M.-L.L., conducted theoretical computations. J.Z., X.L., Z.C., M.-L.L. and P.v.R.S. analysed and interpreted the computational data. J.Z., H.X., S.L. and C.Z. drafted the paper, with support from Z.C., X.L., T.W. and Z.X., as well as language editing by P.v.R.S. All authors discussed the results and contributed to the preparation of the final manuscript.

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Correspondence to Jun Zhu or Haiping Xia.

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Supplementary information

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Supplementary information (PDF 2404 kb)

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Crystallographic data for compound 2a. (CIF 26 kb)

Supplementary information

Crystallographic data for compound3a. (CIF 27 kb)

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Crystallographic data for compound 4. (CIF 27 kb)

Supplementary information

Crystallographic data for compound 5. (CIF 27 kb)

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Zhu, C., Li, S., Luo, M. et al. Stabilization of anti-aromatic and strained five-membered rings with a transition metal. Nature Chem 5, 698–703 (2013). https://doi.org/10.1038/nchem.1690

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