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.


Catalysis Phenyl Pyridinium Benzaldehyde Alkoxide 


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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

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