Quinone methide dimers lacking labile hydrogen atoms are surprisingly excellent radical-trapping antioxidants.

ABSTRACT: Hydrogen atom transfer (HAT) is the mechanism by which the vast majority of radical-trapping antioxidants (RTAs), such as hindered phenols, inhibit autoxidation. As such, at least one weak O-H bond is the key structural feature which underlies the reactivity of phenolic RTAs. We recently observed that quinone methide dimers (QMDs) synthesized from hindered phenols are significantly more reactive RTAs than the phenols themselves despite lacking O-H bonds. Herein we describe our efforts to elucidate the mechanism by which they inhibit autoxidation. Four possible reaction paths were considered: (1) HAT from the C-H bonds on the carbon atoms which link the quinone methide moieties; (2) tautomerization or hydration of the quinone methide(s) in situ followed by HAT from the resultant phen

SUBMITTER: Raycroft MAR 

PROVIDER: S-EPMC7422964 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature