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Main-group elements as transition metals

Abstract

The last quarter of the twentieth century and the beginning decade of the twenty-first witnessed spectacular discoveries in the chemistry of the heavier main-group elements. The new compounds that were synthesized highlighted the fundamental differences between their electronic properties and those of the lighter elements to a degree that was not previously apparent. This has led to new structural and bonding insights as well as a gradually increasing realization that the chemistry of the heavier main-group elements more resembles that of transition-metal complexes than that of their lighter main-group congeners. The similarity is underlined by recent work, which has shown that many of the new compounds react with small molecules such as H2, NH3, C2H4 or CO under mild conditions and display potential for applications in catalysis.

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Figure 1: Bonding in group 14 analogues of ethylene and alkynes.
Figure 2: Similarity of H 2 interactions with main-group and transition-metal compounds.
Figure 3: The reactions of various main-group and transition-metal species with H2 or NH3.
Figure 4: Reversible reactions of main-group compounds with unsaturated molecules.
Figure 5: Catalytic cycle for the reduction of imines by phosphine-boranes.
Figure 6: Structures and reactions of main-group diradicaloids.

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References

  1. Power, P. P. π-bonding and the lone-pair effect in multiple bonds between heavier main group elements. Chem. Rev. 99, 3463–3503 (1999)

    Article  CAS  Google Scholar 

  2. Gaspar, P. P. & West, R. Silylene Chemistry of Organic Silicon Compounds 2, Part 3 (eds Rappoport, Z. & Apeloig, Y.) 2463–2568 (Wiley, 1998)

    Book  Google Scholar 

  3. Mizuhata, Y., Sasamori, T. & Tokitoh, N. Stable heavier carbene analogues. Chem. Rev. 109, 3479–3511 (2009)

    Article  CAS  Google Scholar 

  4. Linti, G. & Schnöckel, H. Low valent aluminum and gallium compounds, structural variety and coordination modes to transition metal fragments. Coord. Chem. Rev. 206–207, 285–319 (2000)

    Article  Google Scholar 

  5. Stephan, D. W. Frustrated Lewis pairs: a new strategy to small molecule activation and hydrogenation catalysis. Dalton Trans. 3129–3136 (2009)

  6. Power, P. P. Persistent and stable radicals of the heavier group elements and related species. Chem. Rev. 103, 739–809 (2003)

    Article  Google Scholar 

  7. Hicks, R. G. What’s new in stable radical chemistry. Org. Mol. Biochem 5, 1321–1338 (2007)

    CAS  Google Scholar 

  8. Lee, V., Ya, Nakamoto, M. & Sekiguchi, A. Making stable radicals of heavy elements of group 14 and 13: the might of silyl substitution. Chem. Lett. 37, 128–133 (2008)

    Article  CAS  Google Scholar 

  9. Breher, F. Stretching bonds in main group element compounds — borderlines between biradical and closed shell species. Coord. Chem. Rev. 215, 1007–1043 (2007)

    Article  Google Scholar 

  10. Dasent, W. E. Nonexistent Compounds (Marcel Dekker, 1965)

    Google Scholar 

  11. Taylor, M. J. Metal-to-Metal Bonded States (Academic, 1975)

    Google Scholar 

  12. Pearson, R. G. Electronic spectra and chemical reactivity. J. Am. Chem. Soc. 110, 2092–2097 (1988)

    Article  CAS  Google Scholar 

  13. Kutzelnigg, W. Chemical bonding in higher main group elements. Angew. Chem. Int. Edn Engl. 23, 272–295 (1984)

    Article  Google Scholar 

  14. Jacobsen, H. & Ziegler, T. Nonclassical double bonds in ethylene analogues: influence of Pauli repulsion on trans-bending and π-bond strength; a density functional study. J. Am. Chem. Soc. 116, 3667–3679 (1994)

    Article  CAS  Google Scholar 

  15. Wells, A. F. Structural Inorganic Chemistry 5th edn 1279 (Clarendon, 1986)

    Google Scholar 

  16. Davidson, P. J. & Lappert, M. F. Stabilization of metals in a low-coordination environment using the bis(trimethylsilyl)methyl ligand: coloured SnII and PbII alkyls M{CH(SiMe3)2}2 . J. Chem. Soc. Chem. Commun. 317 (1973)This paper (and ref. 17) established the existence of heavier main group element analogues of ethylene in the solid state, which displayed large structural differences from their lighter element counterparts.

  17. Goldberg, D. E., Harris, D. H., Lappert, M. F. & Thomas, K. M. A new synthesis of divalent group 4B alkyls M[CH(SiMe3)2]2 (M = Ge or Sn) and the crystal structure of the tin compound. J. Chem. Soc. Chem. Commun. 261–262 (1976)

  18. Goldberg, D. E. et al. Subvalent group 4B alkyls and amides. Part 9 germanium and tin alkene analogues, the dimetallenes M2R4 [M = Ge or Sn; R = CH(SiMe3)2]. X-ray structures, molecular orbital calculations for M2H4 and trends in the series M2R4 1 [M = C, Si, Ge or Sn; R1 = R, Ph, C6H2-Me3-2,4,6 or C6H3Et2-2,6]. J. Chem. Soc. Dalton Trans. 2387–2394 (1986)

  19. Stürmann, M., Weidenbruch, M., Klinkhammer, K. W., Lissner, F. & Marsmann, H. New plumbylenes and a plumbylene dimer with a short lead-lead separation. Organometallics 17, 4425–4428 (1998)

    Article  Google Scholar 

  20. West, R., Fink, M. J. & Michl, J. Tetramesityldisilene, a stable compound with a silicon-silicon double bond. Science 214, 1343–1344 (1981)Described the synthesis and structure of the first stable (that is, non-dissociating) compound with a double bond between two heavier main group elements and (with ref. 35) effectively overthrew the so-called double bond rule, which holds that heavier main group elements do not form stable double bonds (see refs 10 and 13).

    Article  ADS  CAS  Google Scholar 

  21. Sekiguchi, A., Kingo, R. & Ichinohe, M. A stable compound with a silicon-silicon triple bond. Science 305, 1755–1757 (2004)

    Article  ADS  CAS  Google Scholar 

  22. Stender, M., Phillips, A. D., Wright, R. J. & Power, P. P. Synthesis and characterization of a digermanium analogue of an alkyne. Angew. Chem. Int. Edn 41, 1785–1787 (2002)

    Article  CAS  Google Scholar 

  23. Phillips, A. D., Wright, R. J., Olmstead, M. M. & Power, P. P. Synthesis and characterization of 2,6-Dipp2-H3C6SnSnC6H3-2,6-Dipp2 (Dipp = C6H3-2,6-Pri 2): a tin analogue of an alkyne. J. Am. Chem. Soc. 124, 5930–5931 (2002)

    Article  CAS  Google Scholar 

  24. Pu, L., Twamley, B. & Power, P. P. Synthesis and characterization of 2,6-Trip2H3C6PbPbC6H3-2,6-Trip2 (Trip = C6H2-2,4,6-i-Pr3): a stable heavier group 14 element analogue of an alkyne. J. Am. Chem. Soc. 122, 3524–3525 (2000)

    Article  CAS  Google Scholar 

  25. Bader, R. F. W. Vibrationally induced perturbations of molecular electron distribution. Can. J. Chem. 40, 1164–1175 (1962)Showed how certain vibrational modes permitted symmetry allowed second order Jahn–Teller mixing, which could lead to large geometrical perturbations.

    Article  CAS  Google Scholar 

  26. Pearson, R. G. Symmetry rule for predicting molecular structure. J. Am. Chem. Soc. 91, 4947–4955 (1969)

    Article  CAS  Google Scholar 

  27. Pearson, R. G. Concerning Jahn-Teller effects. Proc. Natl Acad. Sci. USA 72, 2104–2106 (1975)

    Article  ADS  CAS  Google Scholar 

  28. Grev, R. S. Structure and bonding in the parent hydrides and multiple bonded silicon and germanium compounds: from MHn to R2M = M'R2 and RM≡M'R. Adv. Organomet. Chem. 33, 125–170 (1991)

    Article  CAS  Google Scholar 

  29. Albright, T. A., Burdett, J. K. & Whangbo, M. H. Orbital Interactions in Chemistry 166–177 (Wiley, 1985)

    Google Scholar 

  30. Carter, E. A. & Goddard, W. A. Relation between the singlet-triplet gaps and bond energies. J. Phys. Chem. 90, 998–1001 (1986)

    Article  CAS  Google Scholar 

  31. Trinquier, G. & Malrieu, J.-P. Non-classical distortions at multiple bonds. J. Am. Chem. Soc. 109, 5303–5315 (1987)

    Article  CAS  Google Scholar 

  32. Grützmacher, H. & Fässler, T. Topographical analysis of homonuclear multiple bonds between main group elements. Chem. Eur. J. 6, 2317–2325 (2000)

    Article  Google Scholar 

  33. Su, J., Li, X.-W., Crittendon, R. C. & Robinson, G. H. How short is a Ga-Ga triple bond? Synthesis and molecular structure of Na2[Mes*2C6H3GaGaC6H3-Mes*2] (Mes* = 2,4,6-Pri 3C6H3): the first gallyne. J. Am. Chem. Soc. 119, 5471–5472 (1997)Reported the first formal triple bond between two main group metals, but because the multiple bond was bridged by alkali metal ions and its structure was strongly bent, its description as triple-bonded initiated an illuminating debate on multiple bonding between main group elements.

    Article  CAS  Google Scholar 

  34. Zhu, Z. et al. Synthesis, characterization and real molecule calculations for neutral organogallium(I) aryl dimers and monomers: weakness of gallium-gallium bonds in digallenes and digallynes. Chem. Eur. J. 15, 5263–5272 (2009)

    Article  CAS  Google Scholar 

  35. Yoshifuji, M., Shima, I., Inamoto, N., Hirotsu, K. & Higuchi, T. Synthesis and structure of bis(2,4,6-tri-tert-butylphenyl)diphosphene: isolation of a true phosphabenzene. J. Am. Chem. Soc. 103, 4587–4589 (1981)Along with the disilene in ref. 20, the description of the first stable phosphorus–phosphorus double bond vitiated the double bond rule.

    Article  CAS  Google Scholar 

  36. Tokitoh, N., Arai, Y., Okazaki, R. & Nagase, S. Synthesis and characterization of a stable dibismuthene: evidence for a bismuth-bismuth double bond. Science 277, 78–80 (1997)

    Article  CAS  Google Scholar 

  37. Kubas, G. J. Metal Dihydrogen and σ-Bond Complexes: Structure, Theory and Reactivity (Kluwer Academic, 2001)

    Google Scholar 

  38. Spikes, G. H., Fettinger, J. C. & Power, P. P. Facile activation of dihydrogen by an unsaturated heavier main group compound. J. Am. Chem. Soc. 127, 12232–12233 (2005)Reported the first uncatalysed reactions of H 2 with a main group molecule under ambient conditions.

    Article  CAS  Google Scholar 

  39. Peng, Y. et al. Addition to H2 to distannynes under ambient conditions. Chem. Commun. (Camb.) 6042–6044 (2008)

  40. Zhu, Z. et al. Addition of hydrogen or ammonia to a low valent group 13 metal species at 25°C and 1 atmosphere. Angew. Chem. Int. Edn 48, 2031–2033 (2009)

    Article  CAS  Google Scholar 

  41. Frey, G. D., Lavallo, B., Donnadieu, B., Schoeller, W. W. & Bertrand, G. Facile spitting of hydrogen and ammonia by nucleophilic activation at a single carbon center. Science 316, 439–441 (2007)Reported the first reactions of a carbene with H 2 and NH 3 under ambient conditions.

    Article  ADS  CAS  Google Scholar 

  42. Welch, G. C., San Juan, R. R., Masuda, J. D. & Stephan, D. W. Reversible metal-free hydrogen activation. Science 314, 1124–1128 (2006)Introduced the frustrated Lewis pair concept and showed how a phosphine borane combination could reversibly bind H 2 under near-ambient conditions.

    Article  ADS  CAS  Google Scholar 

  43. Chase, P. A. & Stephan, D. W. Hydrogen and amine activation by a frustrated Lewis pair of a bulky N-heterocyclic carbene and B(C6F5)3 . Angew. Chem. Int. Edn 47, 7433–7437 (2008)

    Article  CAS  Google Scholar 

  44. Holschumacher, D., Bannenberg, T., Hrib, C. G., Jones, P. G. & Tamm, M. Heterolytic dihydrogen activation by frustrated carbene-borane Lewis pair. Angew. Chem. Int. Edn 47, 7428–7432 (2008)

    Article  CAS  Google Scholar 

  45. Sumerin, V. et al. Facile heterolytic H2 activation by amines and B(C6F5)3 . Angew. Chem. Int. Edn 47, 6001–6003 (2008)

    Article  CAS  Google Scholar 

  46. Sumerin, V. et al. Molecular tweezers for hydrogen: synthesis and characterization and reactivity. J. Am. Chem. Soc. 130, 14117–14118 (2008)

    Article  CAS  Google Scholar 

  47. Wang, H., Frölich, R., Kehr, G. & Erker, G. Heterolytic dihydrogen activation with the 1,8-bis(diphenylphosphino) naphthalene/B(C6F5)3 pair and its application for metal free catalytic hydrogenation of silylenol ethers. Chem. Commun. (Camb.) 5966–5968 (2008)

  48. Peng, Y., Ellis, B. D., Wang, X. & Power, P. P. Diarylstannylene activation of hydrogen or ammonia with arene elimination. J. Am. Chem. Soc. 130, 12268–12269 (2008)

    Article  CAS  Google Scholar 

  49. Zhao, J., Goldman, A. S. & Hartwig, J. S. Oxidative addition of ammonia to form a stable, monomeric amino hydride complex. Science 307, 1080–1082 (2005)

    Article  ADS  CAS  Google Scholar 

  50. Power, P. P. The bonding and reactivity of heavier group 14 alkyne analogues. Organometallics 26, 4362–4372 (2007)

    Article  CAS  Google Scholar 

  51. Stender, M., Phillips, A. D. & Power, P. P. Formation of [Ar*GE{CH2C(Me)C(Me)CH2}CH2C(Me)=]2 (Ar* = C6H3-2,6-Trip2; Trip = C6H2-2,4,6-i-Pr3) via reaction of Ar*GeGeAr* with 2,3-dimethyl-1,3-butadiene: evidence for the existence of a germanium analogue of an alkyne. Chem. Commun. 1312–1313 (2002)

  52. Kinjo, R. et al. Reactivity of the disilyne RSiSiR (R = SiiPr[CH(SiMe3)2]2) toward π-bonds: stereo specific addition and a new route to an isolable 1,2-disilabenzene. J. Am. Chem. Soc. 129, 7766–7767 (2007)

    Article  CAS  Google Scholar 

  53. McCahill, J. S., Welch, G. C. & Stephan, D. W. Reactivity of “frustrated Lewis pairs:” three component reactions of phosphines, a borane and olefin. Angew. Chem. Int. Edn 46, 4968–4971 (2007)

    Article  CAS  Google Scholar 

  54. Sita, L. R. & Bickerstaff, R. D. Synthesis and crystal structure of the first stannacyclopropene derivative. J. Am. Chem. Soc. 110, 5208–5209 (1988)

    Article  CAS  Google Scholar 

  55. Peng, Y., Ellis, B. D., Wang, X., Fettinger, J. C. & Power, P. P. Reversible reactions of ethylene with distannynes under ambient conditions. Science 325, 1668–1670 (2009)This paper and ref. 58 reported reversible binding of the unsaturated species C 2 H 4 and CO 2 by a main group molecule under ambient conditions.

    Article  ADS  CAS  Google Scholar 

  56. Seyferth, D. [(C2H4)PtCl3]-, the anion of Zeise’s salt K[C(C2H4)PtCl3]·H2O. Organometallics 20, 2–6 (2001)

    Article  CAS  Google Scholar 

  57. Otten, E., Neu, R. C., Erker, G. & Stephan, D. W. Complexation of nitrous oxide by frustrated Lewis pairs. J. Am. Chem. Soc. 131, 9918–9919 (2009)

    Article  CAS  Google Scholar 

  58. Mömming, C. M. et al. Reversible metal-free carbon dioxide binding by frustrated Lewis pairs. Angew. Chem. Int. Edn 48, 6643–6646 (2009)

    Article  Google Scholar 

  59. Chase, P. A., Welch, G. C., Junea, T., Erker, G. & Stephan, D. W. Metal-free catalytic hydrogenation. Angew. Chem. Int. Edn 46, 8050–8053 (2007)

    Article  CAS  Google Scholar 

  60. Spies, P. et al. Metal free catalytic hydrogenation of enamines, imines and conjugated phosphinalkenylboranes. Angew. Chem. Int. Edn 47, 7543–7546 (2008)

    Article  CAS  Google Scholar 

  61. Davidson, P. J., Hudson, A., Lappert, M. F. & Lednor, P. W. Tris[bis(trimethylsilyl)methyl]tin(III), R3Sn·: an unusually stable stannyl radical, from photolysis of R2Sn. J. Chem. Soc. Chem. Commun. 829–830 (1973)

  62. Gynane, M. J. S., Hudson, A., Lappert, M. F., Power, P. P. & Goldwhite H Synthesis and electron spin resonance study of stable dialkyls and diamides of phosphorus and arsenic R2 1M·and (R2 2N)2M·. J. Chem. Soc. Chem. Commun. 623–624 (1976)

  63. Chivers, T. A Guide to Chalcogen-Nitrogen Chemistry (World Scientific, 2005)

    Book  Google Scholar 

  64. Niecke, E., Fuchs, A., Baumeister, F., Nieger, M. & Schoeller, W. W. A. P2C2 four-membered ring with unusual bonding synthesis structure and ring opening of a 1,3-diphosphacyclobutane-2,4-diyl. Angew. Chem. Int. Edn Engl. 34, 555–557 (1995)This paper and ref. 65 were the first reports to recognise the existence of stable singlet diradicaloid species.

    Article  CAS  Google Scholar 

  65. Scheschkewitz, D. et al. Singlet diradical from transition states to crystalline compounds. Science 295, 1880–1881 (2002)

    Article  ADS  CAS  Google Scholar 

  66. Sita, L. R. Structure/property relationships of polystannanes. Adv. Organomet. Chem. 38, 189–243 (1995)

    Article  CAS  Google Scholar 

  67. Dai, X., Kapoor, P. & Warren, T. H. [Me2NN]Co(η6-toluene): O = O, N = N and O = N bond cleavage provides β-diketiminato cobalt µ-oxo and imido complexes. J. Am. Chem. Soc. 126, 4798–4799 (2004)

    Article  CAS  Google Scholar 

  68. Cui, C., Brynda, M. A., Olmstead, M. M. & Power, P. P. Synthesis and characterization of the non-Kekule singlet diradicaloid Ar′Ge(µ-NSiMe3)2GeAr′ (Ar′ = 2,6-Dipp2C6H3, Dipp = 2,6-PriC6H3). J. Am. Chem. Soc. 126, 6510–6511 (2004)

    Article  CAS  Google Scholar 

  69. Wang, X., Peng, Y., Olmstead, M. M., Fettinger, J. C. & Power, P. P. An unsymmetric oxo/imido-bridged germanium-centered singlet diradicaloid. J. Am. Chem. Soc. 131, 14164–14165 (2009)

    Article  CAS  Google Scholar 

  70. Schoeller, W. W., Rozhenko, A., Bourissou, D. & Bertrand, G. The electronic structures of 1,3-diboracyclobutane-1,3-diyls and their valence and isomers with a B2E2 skeleton (E = N, P, As). Chem. Eur. J. 9, 3611–3617 (2003)

    Article  CAS  Google Scholar 

  71. Jung, Y. & Head-Gordon, M. Controlling the extent of diradical character by utilizing neighboring group interactions. J. Phys. Chem. A 107, 7475–7481 (2003)

    Article  CAS  Google Scholar 

  72. Seierstad, M., Kinsinger, C. R. & Cramer, C. J. Design optimization of 1,3-diphospha-2,4-diboretane diradicals. Angew. Chem. Int. Edn 41, 3894–3896 (2002)

    Article  CAS  Google Scholar 

  73. Amii, H., Vranicar, H., Gornitzka, H., Bourissou, D. & Bertrand, G. Radical type reactivity of the 1,3-dibora-2,4-diphosphonio cyclo-butane-1,3-diyl. J. Am. Chem. Soc. 126, 1344–1345 (2004)

    Article  CAS  Google Scholar 

  74. Jung, Y., Brynda, M., Power, P. P. & Head-Gordon, M. Calculations on the electronic structure of heavier alkyne congeners: diradical character and reactivity. J. Am. Chem. Soc. 128, 7185–7192 (2006)

    Article  CAS  Google Scholar 

  75. Lee, S. C. & Holm, R. H. Speculative synthetic chemistry and the nitrogenase problem. Proc. Natl Acad. Sci. USA 100, 3595–3600 (2008)

    Article  ADS  Google Scholar 

  76. Resa, I., Carmona, E., Guttierez-Puebla, E. & Monge, A. Decamethyldizincocene a stable compound with a zinc-zinc bond. Science 205, 1136–1138 (2004)

    Article  ADS  Google Scholar 

  77. Green, S. P., Jones, C. & Stasch, A. Stable magnesium(1) compounds. Science 318, 1754–1757 (2007)

    Article  ADS  CAS  Google Scholar 

  78. Wang, Y. et al. A stable silicon(O) compound with an Si-Si double bond. Science 321, 106–107 (2008)

    Google Scholar 

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I thank the US NSF and the US Department of Energy Office of Basic Energy Sciences for financial support.

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Power, P. Main-group elements as transition metals. Nature 463, 171–177 (2010). https://doi.org/10.1038/nature08634

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