Evaluation of polar effects in hydrogen atom transfer reactions from activated phenols
Evaluation of polar effects in hydrogen atom transfer (HAT) processes is made difficult by the fact that in most cases substrates characterized by lower bond dissociation energies (BDEs), activated from an enthalpic point of view, are also more activated by polar effects. In search of an exception to this general rule, we found that the introduction of a methoxy substituent in the 3-position of 2,6-dimethylphenol results in a small increase in the O-H BDE and a decrease of the ionization potential of the phenol.