Send to

Choose Destination
See comment in PubMed Commons below
J Org Chem. 2002 Jul 12;67(14):4828-32.

Determination of the substituent effect on the O-H bond dissociation enthalpies of phenolic antioxidants by the EPR radical equilibration technique.

Author information

Dipartimento di Chimica Organica A. Mangini, Università di Bologna, Via S. Donato 15, I-40127 Bologna, Italy.


The bond dissociation enthalpies (BDE) of several phenols containing electron-withdrawing substituents in the para position have been determined by means of the EPR radical equilibration technique. It has been found that CN, NO(2), CHO, COOR, and COOH induce an increase of the BDE value of the O-H bond, thus producing a worsening of the antioxidant activity of phenols, while Cl, Ph, and CH[double bond]CHPh show an opposite effect. The contributions of these substituents for the calculation of the BDE values in polysubstituted phenols by using the group additivity rule have also been derived. It is shown that this rule provides quite reliable predictions of bond strengths, so that the method can be conveniently used to estimate new data on substituted phenols.

PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for American Chemical Society
    Loading ...
    Support Center