| Abstract
| - Aryl radical anions created in liquid alcohols decay on the microsecond time scale by transfer of protonsfrom the solvent. This paper reports a 4.5 decade range of rate constants for proton transfer from a singleweak acid, ethanol, to a series of unsubstituted aryl radical anions, Ar-•. The rate constants correlate withfree energy change, ΔG°, despite wide variations in the two factors that contribute to ΔG°: (a) the reductionpotentials of the aryls and (b) the Ar−H• bond strengths in the product radicals. For aryl radical anionscontaining CH2OH substituents, such as 2,2‘-biphenyldimethanol•- which is protonated with a rate constantof 3 × 109 s-1, the faster rates do not fit well in the free energy correlation, suggesting a change in mechanism.
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