The Transition State of the Acid Catalyzed Alkoxide Ion Departure from Meisenheimer Complexes (1)

  • Claude F. Bernasconi
  • Joseph R. Gandler
Conference paper
Part of the NATO Advanced Study Institutes Series book series (ASIC, volume 50)


Alkoxide ion departure from Meisenheimer complexes of the 1,1-dialkoxy-2,6-dinitro-4-X-cyclohexadienate type is catalyzed by pyridinium ions and by the hydronium ion. Bronsted α values which vary between 0.35 and 0.65 decrease when the alkoxy group becomes more electron withdrawing and increase when the X-substituent is made more electron withdrawing. This is inconsistent with a mechanism where proton transfer is rate limiting but in complete agreement with a concerted mechanism of acid catalysis as shown with the help of More O’Ferrall-Jencks energy diagrams.


Transition State Proton Transfer Reaction Coordinate Alkoxy Group Energy Diagram 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    For a more detailed account of this work see Bernasconi, C. F. and Gandler, J. R.: 1978, J. Am. Chem. Soc. 100, 8117.CrossRefGoogle Scholar
  2. 2.
    Crampton, M. R. and Willison, M. J.: 1974, Chem. Soc., Perkin Trans. 2, p. 1686.CrossRefGoogle Scholar
  3. 3.
    Eigen, M.: 1964, Angew. Chem. Int. Ed. Engl. 3, p. 1.CrossRefGoogle Scholar
  4. 4.
    Jencks, W. P.: 1976, Acc. Chem. Res. 9, p. 425.CrossRefGoogle Scholar
  5. 5.
    Jencks, W. P.: 1972, Chem. Rev. 72, p. 705.CrossRefGoogle Scholar
  6. 6.
    Jencks, D. A. and Jencks, W. P.: 1977, J. Am. Chem. Soc. 99, p. 7948.CrossRefGoogle Scholar
  7. 7.
    More O’Ferrall, R. A.: 1970, J. Chem. Soc. B, p. 274.Google Scholar
  8. 8.
    Hammond, G. S.: 1955, J. Am. Chem. Soc. 77, p. 334.CrossRefGoogle Scholar
  9. 9.
    Thornton, E. R.: 1967, J. Am. Chem. Soc. 89, p. 2915.CrossRefGoogle Scholar
  10. 10.
    Gravitz, N. and Jencks, W. P.: 1974, J. Am. Chem. Soc. 96, p. 507.CrossRefGoogle Scholar
  11. 11.
    Sayer, J. M. and Jencks, W. P.: 1977, J. Am. Chem. Soc. 99, p. 464.CrossRefGoogle Scholar
  12. 12.
    Funderbunk, L. H., Aldwin, L., and Jencks, W. P.: 1978, J. Am. Chem. Soc. 100, p. 5444.CrossRefGoogle Scholar
  13. 13.
    Capon, B. and Nimmo, K.: 1975, J. Chem. Soc, Perkin Trans. 2, p. 1113.Google Scholar

Copyright information

© D. Reidel Publishing Company 1979

Authors and Affiliations

  • Claude F. Bernasconi
    • 1
  • Joseph R. Gandler
    • 1
  1. 1.Thimann LaboratoriesUniversity of CaliforniaSanta CruzUSA

Personalised recommendations