Elsevier

Tetrahedron

Volume 53, Issue 29, July 1997, Pages 10029-10040
Tetrahedron

From Pagodanes to Dodecahedranes - Search for a Serviceable Access to the Parent (C20H20) Hydrocarbon**

https://doi.org/10.1016/S0040-4020(97)00345-1Get rights and content

Abstract

By taking advantage of the novel SN2 pagodane → dodecahedrane routes a preparatively potent access to the parent pentagonal dodecahedrane (2) was explored. The one-pot catalytic procedure (Pd/C/H2) starting from an eightfold functionalized secopagodane (14, C20H12Br6 (CO2 CH3)2) excells in shortness but, rather erratic (33–53%), falls out of the competition. The longer route via 1,6-dicarboxyl/dibromo dodecahedranes (35, 22) turned out as first choice with a total yield of 74–76% based on the common pagodane precursor (13). © 1997 Elsevier Science Ltd.

Section snippets

Introduction - Prior work

The parent pentagonal dodecahedrane 2 was a widely sought target in organic synthesis.[1]Subsequent to the first success by the Paquette group[2]our pagodane-dodecahedrane scheme[3]developed into a powerful synthetic alternative (aldol-, SN2-approaches[4]). Dodecahedrane 2 enjoys renewed prominence being perhydro C20 fullerene.5, 6In this paper we detail our activities directed toward a serviceable synthesis of 2 which were originally based on the SN2 pagodane → dodecahedrane route[3]and were

Starting from “SN2-intermediates”

The three versions of the SN2-route from 4-syn,9-syn-pagodane-diester 13 - a direct offspring of the pagodane synthesis[13]- to functionalized dodecahedranes made the variously brominated diesters 14 - 17 (derivatives of 7, 8 (‘B’) and 3 (‘A’) in Scheme. 1) available in preparative (g) quantities.4, 7There was therefore enough impetus to check their potential as precursors of 2 under the conditions of a short one-pot hydrogenative/debrominative procedure in spite of the potential limitations

Facit

The route from pagodane-diester 13 via its hexabromo derivative 14 (SN2-New(1)[7]) into parent dodecahedrane 2 excells by its shortness but cannot meet the preparative standard. With the SN2-New(2) route from 13 to dodecahedrane-diester 23 and the Barton degradation (23→)35 → 22 → 2 the goal is now reached starting from 13 in six highly optimized, expeditious operations (13 → 33 → 34 → 23 → 35 → 22 → 2), with a

total yield of 74–76% on the 500 mg – 1 g scale. The working time is now measured in

Experimental

Experimental data were recorded using the following: Melting points (mp), Bock Monoscop M; analytical TLC, Merck silica gel plates with F254 indicator; IR, Perkin-Elmer 457 and Philips PU 9706; UV, Perkin-Elmer Lambda 15; 1H NMR, Bruker WM 250, AM 400 (if not specified otherwise, the 400 MHz spectra are given); 13C NMR, AM 400, (100.6 MHz); MS, Finnigan MAT 312 (70 eV). Chemical shifts were recorded relative to TMS (δ = 0), and coupling constants are in Hertz. For signal assignment, standard

Acknowledgements

Financial support by the Deutsche Forschungsgemeinschaft, the Fonds der Chemischen Industrie and the BASF AG is gratefully acknowledged. We thank G. Fehrenbach for graphical work, J. Leonhardt, G. Leonhardt-Lutterbeck, S. Ruf, A. Kurscheidt, F. Reinbold, M. Schonhard, C. Warth, B. Lenhard for competent assistance, Dr. D. Hunkler for NMR analyses, and Dr. L. Knothe for help with the manuscript.

References (38)

  • G. Mehta, J. Sci. Ind. Res. 1978, 37, 256; P.E. Eaton, Tetrahedron 1979, 35, 2189; W. Grahn, Chem. Unserer Zeit 1981,...
  • (a) R.J. Ternansky, D.W. Balogh, L.A. Paquette, J. Am. Chem. Soc. 1982, 104, 4503; (b) L.A. Paquette, R.J. Ternansky,...
  • H. Prinzbach, W.-D. Fessner, in Organic Syntheses: Modern Trends (Ed.: O. Chizhov), Blackwell, Oxford 1987, p. 103;...
  • R. Pinkos, J.-P. Melder, K. Weber, D. Hunkler, H. Prinzbach, J. Am. Chem. Soc. 1993, 115, 7173; J.-P. Melder, R....
  • F. Wahl et al.

    Angew. Chem. Int. Ed. Engl.

    (1993)
  • J.-P. Melder et al.

    Res. Chem. Intermed.

    (1996)
  • M. Bertau et al.

    Chem. Eur. J.

    (1996)
  • W.-D. Fessner, Dissertation, University of Freiburg,...
  • W.-D. Fessner, B.A.R.C. Murty, J. Wörth, D. Hunkler, H. Fritz, H. Prinzbach, W.D. Roth, P. von R. Schleyer, A.B....
  • G.K.S. Prakash, V.V. Krishnamurthy, R. Herges, R. Bau, H. Yuan, G.A. Olah, W.-D. Fessner, H. Prinzbach, J. Am. Chem....
  • B.A.R.C. Murty, R. Pinkos, P.R. Spurr, W.-D. Fessner, G. Lutz, H. Fritz, D. Hunkler, H. Prinzbach, Chem. Ber. 1992,...
  • G. Lutz et al.

    Chem. Ber.

    (1992)
  • W.-D. Fessner, G. Sedelmeier, P.R. Spurr, G. Rihs, H. Prinzbach, J. Am. Chem. Soc. 1987, 109, 4626. In the meantime...
  • M. Bertau, Dissertation, University of Freiburg, in...
  • R. Pinkos, G. Lutz, K. Scheumann, K. Weber, Dissertations, University of Freiburg, 1990, 1990, 1993,...
  • H.-D. Beckhaus, C. Rüchardt, D.L. Lagerwall, L.A. Paquette, F. Wahl, H. Prinzbach, J. Am. Chem. Soc. 1994, 116, 11775;...
  • L.A. Paquette, J.C. Weber, T. Kobayashi, J. Am. Chem. Soc. 1988, 110, 1303; L.A. Paquette, J.C. Weber, T. Kobayashi, K....
  • W.F. Maier, W. Roth, I. Thies, P. von R. Schleyer, Chem. Ber. 1982, 115, 808; P. Grubmüller, W.F. Maier, P. von R....
  • V. Prelog et al.

    Ber. Dtsch. Chem. Ges.

    (1941)
  • Cited by (47)

    • A symmetry-driven approach toward the total synthesis of dodecahedrane

      2022, Tetrahedron
      Citation Excerpt :

      With ketone 10 in hand, efforts were undertaken to achieve the desired homocoupling to generate dimer 11. Following extensive optimization [16], a SmI2-mediated pinacol coupling was found to reliably generate dimer 11 in 43% yield, thus forming a highly congested C–C bond with complete facial selectivity [17]. It was found that high reaction concentration (0.3 M) was critical to promoting dimerization over reduction.

    • Theoretical study on the mechanism of reactions of CX<inf>3</inf> radicals (X = H, F, Cl and Br) with C<inf>20</inf>H<inf>20</inf> and C<inf>20</inf>F<inf>20</inf> fullerenes

      2017, Journal of Molecular Structure
      Citation Excerpt :

      Chen et al. [28] demonstrates that all these five isomers are isoenergetic and have about the same structural parameters. Despite its labile nature, successful production of the C20 fullerene is accomplished via stable dodecahedrane (C20H20) in gas phase on the microsecond-scale lifetime [29–31]. Dodecahedrane (C20H20), as a fascinating molecule with unusually high symmetry (Ih), is the only fully hydrogenated fullerene which has been synthesized up to now.

    View all citing articles on Scopus
    **

    Dedicated to Professor W. von E. Doering on the occasion of his 80th birthday. H.P. very fondly remembers his two post-doc years at Yale University (1957–59).

    View full text