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  • Review Article
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Molecular pyramids — from tetrahedranes to [6]pyramidanes

Nature Reviews Chemistry volume 7, pages 732–746 (2023)Cite this article

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Abstract

The study of 3D architectures at a molecular scale has fascinated chemists for generations. This includes molecular pyramids with all-carbon frameworks, such as trigonal, tetragonal and pentagonal pyramidal geometries. A small number of substituted tetrahedranes and all-carbon [4]–[5]pyramidanes have been experimentally generated and studied. Although the hypothetical unsubstituted parent [3]–[6]pyramidanes have only been explored computationally, the formal replacement of carbon vertices with isolobal main group element fragments has provided a number of examples of stable hetero[m]pyramidanes, which have been isolated and amply characterized. In this Review, we highlight the synthesis and chemical properties of [3]–[6]pyramidanes and summarize the progress in the development of chemistry of pyramid-shaped molecules.

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Fig. 1: The four fundamental molecular pyramids, [3]–[6]pyramidane.
Fig. 2: Examples of [3]pyramidanes, the tetrahedranes.
Fig. 3: Syntheses, reactions and bonding features of [4]pyramidane examples.
Fig. 4: All-carbon [5]pyramidanes and isolobal main group element derivatives.
Fig. 5: Additional hetero[5]pyramidane chemistry.
Fig. 6: Formation and reactions of functionalized heteroatom containing [5]pyramidane examples.
Fig. 7: [6]Pyramidane examples and a pyramidane construction model.

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References

  1. La Commission des sciences et des arts. Description de I’Égypte (French Government, 1809–1828).

  2. Stohrer, W.-D. & Hoffmann, R. Bond-stretch isomerism and polytopal rearrangements in (CH)5+, (CH)5−, and (CH)4CO. J. Am. Chem. Soc. 94, 1661–1668 (1972).

    Article  CAS  Google Scholar 

  3. Hoffmann, R. Building bridges between inorganic and organic chemistry (Nobel Lecture). Angew. Chem. Int. Ed. 21, 711–724 (1982).

    Article  Google Scholar 

  4. Minkin, V. I., Minyaev, R. M. & Hoffmann, R. Non-classical structures of organic compounds: unusual stereochemistry and hypercoordination. Russ. Chem. Rev. 71, 869–892 (2002).

    Article  CAS  Google Scholar 

  5. Wade, K. The structural significance of the number of skeletal bonding electro-pairs in carboranes, the higher boranes and borane anions, and various transition-metal carbonyl cluster compounds. J. Chem. Soc. D 792–793 (1971).

  6. Rudolph, R. W. Boranes and heteroboranes: a paradigm for the electron requirements of clusters? Acc. Chem. Res. 9, 446–452 (1976).

    Article  CAS  Google Scholar 

  7. Mingos, D. M. P. Polyhedral skeletal electron pair approach. Acc. Chem. Res. 17, 311–319 (1984).

    Article  CAS  Google Scholar 

  8. Schwarz, H. Pyramidal carbocations. Angew. Chem. Int. Ed. 20, 991–1003 (1981).

    Article  Google Scholar 

  9. Hogeveen, H. & Kwant, P. W. Pyramidal mono- and dications: bridge between organic and organometallic chemistry. Acc. Chem. Res. 8, 413–420 (1975).

    Article  CAS  Google Scholar 

  10. Schmidbaur, H., Thewalt, U. & Zafiropoulos, T. Preparation and structure of (η6-hexamethylbenzene)gallium(I) tetrabromogallate(III): π-complex and nido-cluster. Angew. Chem. Int. Ed. 23, 76–77 (1984).

    Article  Google Scholar 

  11. Schorpp, M., Rein, S., Weber, S., Scherera, H. & Krossing, I. Guilty and charged: a stable solution of the hexamethylbenzene radical cation as a ligand forming oxidising agent. Chem. Commun. 54, 10036–10339 (2018).

    Article  CAS  Google Scholar 

  12. Masamune, S. Some aspects of strained systems. [4]Annulene and its CH+ adduct. Pure Appl. Chem. 44, 861–884 (1975).

    Article  CAS  Google Scholar 

  13. Maier, G. Tetrahedrane and cyclobutadiene. Angew. Chem. Int. Ed. 27, 309–332 (1988).

    Article  Google Scholar 

  14. Canac, Y. & Bertrand, G. nido-Five-vertex clusters: in and out of boron chemistry. Angew. Chem. Int. Ed. 42, 3578–3580 (2003).

    Article  CAS  Google Scholar 

  15. Berndt, A., Hofmann, M., Siebert, W. & Wrackmeyer, B. Carboranes: from small organoboranes to clusters. in Molecular Clusters of the Main Group Elements (eds Driess, M. & Nöth, H.) 267–309 (Wiley, 2004).

  16. Grimes, R. N. in Carboranes 3rd edn, 23–87 (Elsevier, 2016).

  17. Grahn, W. Platonische Kohlenwasserstoffe. Chem. Unserer Zeit 15, 52–61 (1981).

    Article  CAS  Google Scholar 

  18. Hopf, H. Platonic hydrocarbons. in Classics in Hydrocarbon Chemistry: Syntheses, Concepts, Perspectives (Wiley, 2000).

  19. Eaton, P. E. & Cole, T. W. The Cubane system. J. Am. Chem. Soc. 86, 962–964 (1964).

    Article  CAS  Google Scholar 

  20. Eaton, P. E. & Cole, T. W. Cubane. J. Am. Chem. Soc. 86, 3157–3158 (1964).

    Article  CAS  Google Scholar 

  21. Paquette, L. A. Dodecahedranes and allied spherical molecules. Chem. Rev. 89, 1051–1065 (1989).

    Article  CAS  Google Scholar 

  22. Scott, L. T. & Jones, M. Rearrangements and interconversions of compounds of the formula (CH)n. Chem. Rev. 72, 181–202 (1972).

    Article  CAS  Google Scholar 

  23. Maier, G. The cyclobutadiene problem. Angew. Chem. Int. Ed. 13, 425–438 (1974).

    Article  Google Scholar 

  24. Liebman, J. F. & Greenberg, A. A survey of strained organic molecules. Chem. Rev. 76, 311–365 (1976).

    Article  CAS  Google Scholar 

  25. Masamune, S., Osa, H. & Yamaguchi, H. Thermolysis and photolysis of tricyclo[2.1.0.02,5]penta-3-one derivatives. J. Am. Chem. Soc. 92, 7495–7497 (1970).

    Article  CAS  Google Scholar 

  26. Maier, G., Reisenauer, H. P. & Freitag, H.-A. Photospaltung von überbrückten bicyclobutan-derivaten — ein weg zu tetrahedranen? Tetrahedron Lett. 19, 121–124 (1978).

    Article  Google Scholar 

  27. Baird, N. C. & Dewar, M. J. S. Ground states of σ-bonded molecules. II. Strain energies of cyclopropanes and cyclopropenes. J. Am. Chem. Soc. 89, 3966 (1967).

    Article  CAS  Google Scholar 

  28. Böhm, M. C. & Gleiter, R. Zur tetrahedranbildung aus bicyclobutan-2,4-diyl. Tetrahedron Lett. 19, 1179–1182 (1978).

    Article  Google Scholar 

  29. Schulman, J. M. & Venanzi, T. J. Theoretical study of the tetrahedrane molecule. J. Am. Chem. Soc. 96, 4739–4746 (1974).

    Article  CAS  Google Scholar 

  30. Nemirowski, A., Reisenauer, H. P. & Schreiner, P. R. Tetrahedrane — dossier of an unknown. Chem. Eur. J. 12, 7411–7420 (2006).

    Article  CAS  PubMed  Google Scholar 

  31. Maier, G., Pfriem, S., Schäfer, U. & Matusch, R. Tetra-tert-butyltetrahedrane. Angew. Chem. Int. Ed. 17, 520–521 (1978). This paper contains the report about the synthesis of the first stable tetrahedrane derivative.

    Article  Google Scholar 

  32. Maier, G., Pfriem, S., Schäfer, U., Malsch, K. D. & Matusch, R. Tetra-tert-butyltetrahedran. Chem. Ber. 114, 3965–3987 (1981).

    Article  CAS  Google Scholar 

  33. Maier, G. & Fleischer, F. Ein Alternativer Zugang zum tetra-tert-butyltetrahedran. Tetrahedron Lett. 32, 57–60 (1991).

    Article  CAS  Google Scholar 

  34. Loerzer, Y. et al. Tetra-tert-butyltetrahedrane: 13C–13C coupling constants and hybridization. Angew. Chem. Int. Ed. 22, 878–879 (1983).

    Article  Google Scholar 

  35. Irngartinger, H. et al. Tetra-tert-butyltetrahedrane crystal and molecular structure. Angew. Chem. Int. Ed. 23, 993–994 (1984).

    Article  Google Scholar 

  36. Irngartinger, H., Jahn, R., Maier, G. & Emrich, R. Gas-inclusion crystals of tetra-tert-butyltetrahedrane and its deformation density. Angew. Chem. Int. Ed. 26, 356–357 (1987).

    Article  Google Scholar 

  37. Maier, G. et al. Tetrakis(trimethylsilyl)tetrahedrane. J. Am. Chem. Soc. 124, 13819–13826 (2002).

    Article  CAS  PubMed  Google Scholar 

  38. Sekiguchi, A. & Tanaka, M. Tetrahedranyllithium: synthesis, characterization, and reactivity. J. Am. Chem. Soc. 125, 12684–12685 (2003).

    Article  CAS  PubMed  Google Scholar 

  39. Rauscher, G., Clark, T., Poppinger, D. & Schleyer, P. V. R. C4Li4, tetralithiotetrahedrane? Angew. Chem. Int. Ed. 17, 276–278 (1978).

    Article  Google Scholar 

  40. Wiberg, N., Finger, C. M. M. & Polborn, K. Tetrakis(tri-tert-butylsilyl)-tetrahedro-tetrasilane (tBu3Si)4Si4: the first molecular silicon compound with a Si4 tetrahedron. Angew. Chem. Int. Ed. 32, 1054–1056 (1993).

    Article  Google Scholar 

  41. Riu, M.-L. Y., Jones, R. L., Transue, W. J., Müller, P. & Cummins, C. C. Isolation of an elusive phosphatetrahedrane. Sci. Adv. 6, eaaz3168 (2020).

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  42. Riu, M.-L. Y., Eckhardt, A. K. & Cummins, C. C. Dimerization and cycloaddition reactions of transient tri-tert-butylphosphacyclobutadiene generated by Lewis acid induced isomerization of tri-tert-butylphosphatetrahedrane. J. Am. Chem. Soc. 143, 13005–13009 (2021).

    Article  CAS  PubMed  Google Scholar 

  43. Hierlmeier, G., Coburger, P., Bodensteiner, M. & Wolf, R. Di-tert-butyldiphosphatetrahedrane: catalytic synthesis of the elusive phosphaalkyne dimer. Angew. Chem. Int. Ed. 58, 16918–16922 (2019).

    Article  CAS  Google Scholar 

  44. Riu, M.-L. Y., Ye, M. & Cummins, C. C. Alleviating strain in organic molecules by incorporation of phosphorus: synthesis of triphosphatetrahedrane. J. Am. Chem. Soc. 143, 16354–16357 (2021).

    Article  CAS  PubMed  Google Scholar 

  45. Breunig, J. M., Tofan, D. & Cummins, C. C. Contrasting cyclo-P3 ligand transfer reactivity of valence-isoelectronic aryloxide complexes [(P3)Nb(ODipp)3]− and [(P3)W(ODipp)3]. Eur. J. Inorg. Chem. 2014, 1605–1609 (2014).

    Article  CAS  Google Scholar 

  46. Crossairt, B. M., Diawara, M.-C. & Cummins, C. C. Facile synthesis of AsP3. Science 323, 602 (2009).

    Article  Google Scholar 

  47. Lewars, E. Pyramidane: an ab initio study of the C5H4 potential energy surface. J. Mol. Struct. 423, 173–188 (1998).

    Article  CAS  Google Scholar 

  48. Kenny, J. P., Krueger, K. M., Rienstra-Kiracofe, J. C. & Schaefer, H. F. III C5H4: pyramidane and its low-lying isomers. J. Phys. Chem. A 105, 7745–7750 (2001).

    Article  CAS  Google Scholar 

  49. Lee, V. Y. et al. Pyramidanes. J. Am. Chem. Soc. 135, 8794–8797 (2013).

    Article  CAS  PubMed  Google Scholar 

  50. Jemmis, E. D. & von Ragué Schleyer, P. Aromaticity in three dimensions. 4. Influence of orbital compatibility on the geometry and stability of capped annulene rings with six interstitial electrons. J. Am. Chem. Soc. 104, 4781–4788 (1982).

    Article  CAS  Google Scholar 

  51. Lee, V. Y. et al. Pyramidanes: the covalent form of the ionic compounds. Organometallics 35, 346–356 (2016).

    Article  CAS  Google Scholar 

  52. Lee, V. Y. et al. Pentagermapyramidane: crystallizing the ‘transition-state’ structure. Angew. Chem. Int. Ed. 54, 5654–5657 (2015).

    Article  CAS  Google Scholar 

  53. Feng, J., Leszczynski, J., Weiner, B. & Zerner, M. C. The reaction C3H3+ + C2H2 and the structural isomers of C5H5+. J. Am. Chem. Soc. 111, 4648–4655 (1989).

    Article  CAS  Google Scholar 

  54. Glukhovtsev, M. N., Bach, R. D. & Laiter, S. Computational study of the thermochemistry of C5H5+ isomers: which C5H5+ isomer is the most stable? J. Phys. Chem. 100, 10952–10955 (1996).

    Article  CAS  Google Scholar 

  55. Pantazis, D. A., McGrady, J. E., Lynam, J. M., Russell, C. A. & Green, M. Structure and bonding in the isoelectronic series CnHnP5-n+: is phosphorus a carbon copy? Dalton Trans. 2080-2086 (2004).

  56. Masamune, S., Sakai, M. & Ona, H. Nature of the (CH)5+ species. I. Solvolysis of l,5-dimethyltricyclo[2.1.0.02,5]pent-3-yl benzoate. J. Am. Chem. Soc. 94, 8955–8956 (1972). The generation of an all-carbon [4]pyramidane in superacidic medium is reported.

    Article  CAS  Google Scholar 

  57. Masamune, S., Sakai, M., Ona, H. & Jones, A. J. Nature of the (CH)5+ species. II. Direct observation of the carbonium ion of 3-hydroxyhomotetrahedrane derivatives. J. Am. Chem. Soc. 94, 8956–8958 (1972).

    Article  CAS  Google Scholar 

  58. Döring, S., Erker, G., Fröhlich, R., Meyer, O. & Bergander, K. Reaction of the Lewis acid tris(pentafluorophenyl)borane with a phosphorus ylide: competition between adduct formation and electrophilic and nucleophilic aromatic substitution pathways. Organometallics 17, 2183–2187 (1998).

    Article  Google Scholar 

  59. Lee, V. Y. et al. From borapyramidane to borole dianion. J. Am. Chem. Soc. 140, 6053–6056 (2018). The first bora[4]pyramidane synthesis is described.

    Article  CAS  PubMed  Google Scholar 

  60. Sun, Q. et al. Borole/borapyramidane relationship. J. Am. Chem. Soc. 144, 7815–7821 (2022). This paper contains the description of the borole/bora[4]pyramidane interconversion.

    Article  CAS  PubMed  Google Scholar 

  61. Wrackmeyer, B. & Bihlmayer, C. Unexpected products from the reaction of alkynylstannanes with 9-borabicyclo[3.3.1]nonane. J. Chem. Soc. Chem. Commun. 1093–1094 (1981).

  62. Sebald, A. & Wrackmeyer, B. Organoborierung von Alkinylstannanen XVI. Borol-Synthese über die Organoborierung von Bis(alkinyl)boranen. J. Organomet. Chem. 307, 157–165 (1986).

    Article  CAS  Google Scholar 

  63. Woodward, R. B. & Hoffmann, R. Stereochemistry of electrocyclic reactions. J. Am. Chem. Soc. 87, 395–397 (1965).

    Article  CAS  Google Scholar 

  64. Woodward, R. B. & Hoffmann, R. The conservation of orbital symmetry. Angew. Chem. Int. Ed. 8, 781–853 (1969).

    Article  CAS  Google Scholar 

  65. Lokbani-Azzouz, N. S., Costuas, K., Halet, J.-F. & Saillard, J.-Y. A density functional theory investigation of the polytopal rearrangement of square-based pyramidal clusters: C5H5+, P5+ and Sb5+. J. Mol. Struct. THEOCHEM 571, 1–6 (2001).

    Article  CAS  Google Scholar 

  66. Gapurenko, O. A., Lee, V. Y., Minyaev, R. M. & Minkin, V. I. Theoretical prediction for synthetic realization: pyramidal systems ClE[E’4R4] (E = B-Ga, E = C-Ge, R = SiMe3, SiMetBu2): a DFT study. Heteroatom Chem. 2019, 3659287 (2019).

    Article  Google Scholar 

  67. Lee, V. Y. et al. A cationic phosphapyramidane. Chem. Eur. J. 22, 17585–17589 (2016).

    Article  CAS  PubMed  Google Scholar 

  68. Wettling, T. et al. Cp2Zr complex of a phosphaalkyne dimer as educt in the synthesis of cyclic phosphorus compounds. Angew. Chem. Int. Ed. 30, 207–210 (1991).

    Article  Google Scholar 

  69. Lynam, J. M. et al. Selective preparation of the [3,5-tBu2-1,2,4-C2P3]− ion and synthesis and structure of the cationic species nido-[3,5-tBu2-1,2,4-C2P3]+, isoelectronic with [C5R5]+. Angew. Chem. Int. Ed. 42, 2778–2782 (2003).

    Article  CAS  Google Scholar 

  70. Aysin, R. R. & Bukalo, S. S. Three dimensional aromaticity in pyramidanes C4R4E and Ge4RGe. Mendeleev Commun. 31, 481–483 (2021).

    Article  CAS  Google Scholar 

  71. Ganguly, G., Pathak, S. & Paul, A. Unraveling the stability of cyclobutadiene complexes using aromaticity markers. Phys. Chem. Chem. Phys. 23, 16005–16012 (2021).

    Article  CAS  PubMed  Google Scholar 

  72. Coburger, P., Masero, F., Bösken, J., Mougel, V. & Grützmacher, H. A. Germapyramidane switches between 3D cluster and 2D cyclic structures in single-electron steps. Angew. Chem. Int. Ed. 61, e202211749 (2022).

    Article  CAS  Google Scholar 

  73. Minkin, V. I. & Minyaev, R. M. Pyramidane and pyramidal cations. Dokl. Chem. 385, 203–206 (2002).

    Article  CAS  Google Scholar 

  74. Jutzi, P. et al. The (Me5C5)Si+ cation: a stable derivative of HSi+. Science 305, 849–851 (2004). A stable mono-silicon-containing analogue of the hypothetical all-carbon (C6R5)+ [5]pyramidane cation is described in this publication.

    Article  CAS  PubMed  Google Scholar 

  75. Fritz-Langhals, E. Main group catalysis: cationic Si(II) and Ge(II) compounds as catalysts in organosilicon chemistry. Reactions 2, 442–456 (2021).

    Article  Google Scholar 

  76. Heitkemper, T., Sarcevic, J. & Sindlinger, C. P. A neutral silicon(II) half-sandwich compound. J. Am. Chem. Soc. 142, 21304–21309 (2020).

    Article  CAS  PubMed  Google Scholar 

  77. Tholen, P., Dong, Z., Schmidtmann, M., Albers, L. & Müller, T. A neutral η5-aminoborole complex of germanium(II). Angew. Chem. Int. Ed. 57, 13319–13324 (2018).

    Article  CAS  Google Scholar 

  78. Shen, C.-T., Liu, Y.-H., Peng, S.-M. & Chiu, C.-W. A di-substituted boron dication and its hydride-induced transformation to an NHC-stabilized borabenzene. Angew. Chem. Int. Ed. 52, 13293–13297 (2013).

    Article  CAS  Google Scholar 

  79. Huang, J.-S. et al. Cp*-substituted boron cations: the effect of NHC, NHO, and CAAC ligands. Inorg. Chem. 55, 12427–12434 (2016).

    Article  CAS  PubMed  Google Scholar 

  80. Greiwe, P. et al. Borane-stabilized boranediyls (borylenes): neutral nido-1-borane-2,3,4,5,6-pentamethyl-2,3,4,5,6-pentacarbahexaboranes(6). Eur. J. Inorg. Chem. 1927−1929 (2000).

  81. Cowley, A. H., Lomelí, V. & Voigt, A. Synthesis and characterization of a terminal borylene (boranediyl) complex. J. Am. Chem. Soc. 120, 6401–6402 (1998).

    Article  CAS  Google Scholar 

  82. Jašík, J., Gerlich, D. & Roithová, J. Probing isomers of the benzene dication in a low-temperature trap. J. Am. Chem. Soc. 136, 2960–2962 (2014).

    Article  PubMed  Google Scholar 

  83. Hogeveen, H. & Kwant, P. W. Direct observation of a remarkably stable dication of unusual structure: (CCH3)62+. Tetrahedron Lett. 14, 1665–1670 (1973).

    Article  Google Scholar 

  84. Hogeveen, H., Kwant, P. W., Postma, J. & van Duynen, P. Th. Electronic spectra of pyramidal dications, (CCH3)62+ and (CH)62+. Tetrahedron Lett. 15, 4351–4354 (1974).

    Article  Google Scholar 

  85. Hogeveen, H. & Kwant, P. W. (CCH3)62+, an unusual dication. J. Am. Chem. Soc. 96, 2208–2214 (1974).

    Article  CAS  Google Scholar 

  86. Hogeveen, H. & van Kruchten, E. M. G. A. (CCH3)62+, isotopic perturbation of the carbon-13 nuclear magnetic resonance spectrum of a pyramidal dication. J. Org. Chem. 46, 1350–1353 (1981).

    Article  CAS  Google Scholar 

  87. Malischewski, M. & Seppelt, K. Crystal structure determination of the pentagonal-pyramidal hexamethylbenzene dication C6(CH3)62+. Angew. Chem. Int. Ed. 56, 368–370 (2017). A stable isolated all-carbon [5]pyramidane dication is reported in this paper.

    Article  CAS  Google Scholar 

  88. Zhou, J., Liu, L. L., Cao, L. L. & Stephan, D. W. A phosphorus Lewis super acid: η5-pentamethylcyclopentadienyl phosphorus dication. Chem 4, 2699–2708 (2018).

    Article  CAS  Google Scholar 

  89. Jutzi, P., Seufert, A. & Buchner, W. 1-Halogen-2,3,4,5,6-pentamethyl-2,3,4,5,6-pentacarba-nido-hexaboran(6)-Kationen, ein neuer nido-Carbaboran-Typ. Chem. Ber. 112, 2488–2493 (1979).

    Article  CAS  Google Scholar 

  90. Schurko, R. W. et al. Anisotropic 11B and 13C NMR interaction tensors in decamethylcyclopentadienyl boron complexes. J. Phys. Chem. A 106, 10096–10107 (2002).

    Article  CAS  Google Scholar 

  91. Sun, Q., Mück-Lichtenfeld, C., Kehr, G. & Erker, G. Formation of a hybrid 1-bora-3-boratabenzene heteroarene anion derivative. Angew. Chem. Int. Ed. 61, e202205565 (2022).

    Article  CAS  Google Scholar 

  92. Onak, T. P. & Wong, G. T. F. Preparation of the pentagonal pyramidal carborane, 2,3,4,5-tetracarba-nido-hexaborane(6). J. Am. Chem. Soc. 92, 5226 (1970).

    Article  CAS  Google Scholar 

  93. Weiss, H. G., Lehmann, W. J. & Shapiro, I. Cyclic organodiboranes: 1,2-tetramethylenediborane and 1,2-(1’-methyltrimethylene)-diborane. J. Am. Chem. Soc. 84, 3840–3843 (1962).

    Article  CAS  Google Scholar 

  94. Miller, V. R. & Grimes, R. N. Carborane formation in alkyne-borane gas-phase systems. V.1 Conversion of two-carbon to four-carbon carboranes via alkyne insertion. Nuclear magnetic resonance studies of tetracarba-nido-hexaboranes. Inorg. Chem. 11, 862–865 (1972).

    Article  CAS  Google Scholar 

  95. Binger, P. Darstellung alkylierter tetracarbahexaborane(6), eine Neue Klasse Stabilisierter Organoborane. Tetrahedron Lett. 7, 2675–2680 (1966).

    Article  Google Scholar 

  96. Haase, J. Die Molekülstruktur des hexamethyl-tetracarbahexaborans(6). Z. Naturforsch. 28a, 785–788 (1973).

    Article  Google Scholar 

  97. Nie, Y., Schwiegk, S., Pritzkow, H. & Siebert, W. One-pot synthesis of 1,6-diiodo-2,3,4,5-tetracarba-nido-hexaboranes(6) and mechanistic studies on the reaction system alkynes/BI3/NaK2.8. Eur. J. Inorg. Chem. 2004, 1630–1638 (2004).

    Article  Google Scholar 

  98. Nie, Y., Pritzkow, H. & Siebert, W. Reactivity studies on 2,3,4,5-tetraethyl-1,6-diiodo-2,3,4,5-tetracarba-nido-hexaborane(6): synthesis and structures of new C4B2 nido-carborane derivatives. Eur. J. Inorg. Chem. 2004, 2425–2433 (2004).

    Article  Google Scholar 

  99. Nie, Y., Pritzkow, H., Wadepohl, H. & Siebert, W. Halogen exchange at boron in nido-C4B2 carboranes. J. Organomet. Chem. 690, 4531–4536 (2005).

    Article  CAS  Google Scholar 

  100. Goswami, A., Nie, Y., Oeser, T. & Siebert, W. Reactivity of carboranylacetylenes towards cobalt complexes. Eur. J. Inorg. Chem. 2006, 566–572 (2006).

    Article  Google Scholar 

  101. Killian, L. & Wrackmeyer, B. Organoborierung von Alkinylstannanen : II. Zur Reaktion von Triorganylboranen mit Dialkyldiethinylstannanen. J. Organomet. Chem. 132, 213–221 (1977).

    Article  CAS  Google Scholar 

  102. Wrackmeyer, B. & Kehr, G. Synthesis of 1,6-dihalogeno-2,3,4,5-tetracarba-nido-hexaborane(6) derivatives. J. Organomet. Chem. 501, 87–93 (1995).

    Article  CAS  Google Scholar 

  103. Berger, H.-O., Nöth, H. & Wrackmeyer, B. Bildung und NMR-Spektren von nido-2,3,4,5-tetracarbaboran(6)-derivaten. Chem. Ber. 112, 2884–2893 (1979).

    Article  CAS  Google Scholar 

  104. Wrackmeyer, B. & Kehr, G. Peralkylated 1,4-dibora-2,5-cyclohexadienes — formation and rearrangement into peralkylated nido-2,3,4,5-tetracarbahexaboranes(6). Polyhedron 10, 1497–1506 (1991).

    Article  CAS  Google Scholar 

  105. Wrackmeyer, B. & Glöckle, A. Synthesis of pentaalkyl-6-bromo-2,3,4,5-tetracarba-nido-hexaboranes(6). Z. Naturforsch. 51b, 859–864 (1996).

    Article  Google Scholar 

  106. Wrackmeyer, B. 1,1-Organoboration of alkynylsilicon, -germanium, -tin and -lead compounds. Coord. Chem. Rev. 145, 125–156 (1995).

    CAS  Google Scholar 

  107. Kehr, G. & Erker, G. Advanced 1,1-carboboration reactions with pentafluorophenylboranes. Chem. Sci. 7, 56–65 (2016).

    Article  CAS  PubMed  Google Scholar 

  108. Budzelaar, P. H. M., van der Kerk, S. M., Krogh-Jespersen, K. & Schleyer, P. V. R. Dimerization of borirene to 1,4-diboracyclohexadiene. Structures and stabilities of (CH)4(BH)2 molecules. J. Am. Chem. Soc. 108, 3960–3967 (1986).

    Article  CAS  Google Scholar 

  109. Camp, R. N., Marynick, D. S., Graham, G. D. & Lipscomb, W. N. Classical configurations associated with nonclassical molecules: three carboranes as examples. J. Am. Chem. Soc. 100, 6781–6783 (1978).

    Article  CAS  Google Scholar 

  110. Herberich, G. E., Ohst, H. & Mayer, H. C4B2H6 isomers: destabilization of the nido-carbaborane structure by amino substituents and a novel classical isomer. Angew. Chem. Int. Ed. 23, 969–970 (1984).

    Article  Google Scholar 

  111. Herberich, G. E. & Ohst, H. Die Ersten Komplexen derivate des 1,3-diborabenzols: Zwei [n6-1,3-bis(diisopropylamino)-1,3-dibora-5-cyclohexen-2,4-diyl]eisen-komplexe. J. Organomet. Chem. 307, C16–C18 (1986).

    Article  CAS  Google Scholar 

  112. Enders, M., Pritzkow, H. & Siebert, W. Formation of a 2,5-diborabicycIo[2.l.l]hexane derivative and its conversion to a tetracarbahexaborane. Angew. Chem. Int. Ed. 31, 606–607 (1992).

    Article  Google Scholar 

  113. Michel, H. et al. Equilibria between nonclassical and classical boron compounds, competition between aromaticity in two and three dimensions. Angew. Chem. Int. Ed. 31, 607–610 (1992).

    Article  Google Scholar 

  114. Braunschweig, H., Ghosh, S., Kupfer, T., Radacki, K. & Wahler, J. High-yield synthesis of a hybrid 2,3,4,5-tetracarba-1,6-nido-hexaborane(6) cluster with an exo-polyhedral boracycle. Chem. Eur. J. 17, 4081–4084 (2011).

    Article  CAS  PubMed  Google Scholar 

  115. Braunschweig, H. et al. A combined experimental and theoretical study on the isomers of 2,3,4,5-tetracarba-nido-hexaborane(6) derivatives and their photophysical properties. Chem. Eur. J. 21, 210–218 (2015).

    Article  CAS  PubMed  Google Scholar 

  116. Balzereit, C., Winkler, H.-J., Massa, W. & Berndt, A. A 1,3-diboratabenzene. Angew. Chem. Int. Ed. 33, 2306–2308 (1994).

    Article  Google Scholar 

  117. Scholz, F. et al. Crystal structure determination of the nonclassical 2-norbornyl cation. Science 341, 62–64 (2013).

    Article  CAS  PubMed  Google Scholar 

  118. Winstein, S., Shtavsky, M., Norton, C. & Woodward, R. B. 7-Norbornenyl and 7-norbornyl cations. J. Am. Chem. Soc. 77, 4183–4184 (1955).

    Article  CAS  Google Scholar 

  119. Furubaki, A. & Matsumoto, T. MINDO/3 study of 7-norbornyl, 7-norbornenyl, and 7-norbornadienyl cations. Bull. Chem. Soc. Jpn. 51, 16–20 (1978).

    Article  Google Scholar 

  120. Saxena, A. K. & Hosmane, N. S. Recent advances in the chemistry of carborane metal complexes incorporating d- and f-block elements. Chem. Rev. 93, 1081–1124 (1993).

    Article  CAS  Google Scholar 

  121. Imagawa, T. et al. Stable silapyramidanes. J. Am. Chem. Soc. 145, 4757–4764 (2023).

    Article  CAS  PubMed  Google Scholar 

  122. Lee, V. Y. & Gapurenko, O. A. Pyramidanes: newcomers to anti-van’t Hoff–Le Bel family. Chem. Commun. https://doi.org/10.1039/D3CC02757K (2023).

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  1. Organisch-Chemisches Institut, Universität Münster, Münster, Germany

    Qiu Sun, Christian Mück-Lichtenfeld, Gerald Kehr & Gerhard Erker

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All authors researched data for the article and contributed substantially to discussion of the content. G.E. wrote the article. All authors reviewed and/or edited the manuscript before submission and during the editing process.

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Sun, Q., Mück-Lichtenfeld, C., Kehr, G. et al. Molecular pyramids — from tetrahedranes to [6]pyramidanes. Nat Rev Chem 7, 732–746 (2023). https://doi.org/10.1038/s41570-023-00525-7

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