Bonded peri-interactions govern the rate of racemisation of atropisomeric 8-substituted 1-naphthamides†

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Jonathan Clayden, Catherine McCarthy and Madeleine Helliwell


Abstract

8-Substituted tertiary 1-naphthamides are chiral, atropisomeric compounds at room temperature, and the rate at which they racemise (by rotation about the Ar–CO bond) depends principally on the extent to which the 8-substituent undergoes incipient nucleophilic addition to the amide carbonyl group, as indicated by X-ray crystallography.


References

  1. A. J. Kirby and J. M. Percy, Tetrahedron, 1988, 44, 6903 CrossRef CAS.
  2. A. J. Kirby and J. M. Percy, Tetrahedron, 1988, 44, 6911 CrossRef CAS.
  3. W. B. Schweizer, G. Procter, M. Kaftory and J. D. Dunitz, Helv. Chim. Acta, 1978, 61, 2783 CrossRef CAS.
  4. A. Ahmed, R. A. Bragg, J. Clayden, L. W. Lai, C. McCarthy, J. H. Pink, N. Westlund and S. A. Yasin, Tetrahedron, 1998, 54, 13277 CrossRef CAS.
  5. J. Clayden, Synlett, 1998, 810 CrossRef CAS.
  6. The compounds were made by the methods of refs. 1–3. For further details, see J. Clayden, C. S. Frampton, C. McCarthy and N. Westlund, Tetrahedron, in press Search PubMedSee also A. J. Birch, M. Salahud-Din and D. C. C. Smith, J. Chem. Soc. (C), 1966, 523 Search PubMed; C. Kiefl and A. Mannschreck, Synthesis, 1995, 1033 Search PubMed.
  7. Mannschreck (ref. 9) has determined the barrier to Ar–CO bond rotation of amide 3a by variable temperature HPLC techniques.
  8. M. A. Cuyegkeng and A. Mannschreck, Chem. Ber., 1987, 120, 803 CrossRef CAS.
  9. A. Mannschreck, H. Zinner and N. Pustet, Chimia, 1989, 43, 165 CAS.
  10. W. H. Pirkle, C. J. Welch and A. J. Zych, J. Chromatogr., 1993, 648, 101 CrossRef CAS.
  11. F. Gasparrini, D. Misiti, M. Pierini and C. Villani, Tetrahedron: Asymmetry, 1997, 8, 2069 CrossRef CAS.
  12. M. Oki, Top. Stereochem., 1983, 14, 1 Search PubMed.
  13. E. L. Eliel and S. H. Wilen, Stereochemistry of Organic Compounds, Wiley, New York, 1994 Search PubMed.
  14. For another example of electronic control over the rate of bond rotation in peri-substituted naphthamides, see F. Cozzi, M. Cinquini, R. Annuziata and J. S. Siegel, J. Am. Chem. Soc., 1993, 115, 5330 Search PubMed.
  15. H. B. Bürgi, J. D. Dunitz, J. M. Lehn and G. Wipf, Tetrahedron, 1974, 30, 1563 CrossRef.
  16. J. Clayden, Angew. Chem., Int. Ed. Engl., 1997, 35, 949 CrossRef CAS.
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