Abstract
| - The m-methoxy group is normally electron-withdrawing(EW), σm = +0.12, σm+ = +0.05. The strong EW activityof a phenoxyl radical's O• atom causes the m-methoxy groupto become electron-donating (ED), σm+ = −0.14. In valencebond terms, this can be ascribed to the nonclassical resonancestructures 1c−e. Although it has long been known thatm-methoxy is ED in photoexcited states, it has now beenfound to be ED for homolytic O−H bond breaking inground-state 3-methoxyphenol.
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