Hydrogen Acidities and Brønsted Relations

  • Andrew StreitwieserJr.

Abstract

Hydrogen isotope exchange rates in methanolic sodium methoxide of hydrocarbons having delocalized carbanions give two separate linear Brønsted-type relations when log K values are plotted against the corresponding pKCsCHA values, one of slope 0.36 at 45° applicable to fluorenes and indenes and another of slope 0.58 applicable to polyaryl methanes. Both calculations have been extended by measurements with additional compounds and the intersection of the two correlations has been characterized by phenylene derivatives. The results show that the proton transfer, even of extensively conjiugated hydrocarbons, can show subtle variations between transition states and equilibrium carbanions.

Keywords

Toluene Hydrocarbon Acidity Fluorene Pyrene 

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Copyright information

© Plenum Press, New York 1981

Authors and Affiliations

  • Andrew StreitwieserJr.
    • 1
  1. 1.Department of ChemistryUniversity of CaliforniaBerkeleyUSA

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