Phenol–phenoxyl radical equilibria by electron spin resonance: are radicals derived from tocopherol and analogues exceptionally stabilized?
Abstract
The extra ‘stabilization’ of the 2,2,4,6,7-pentamethyl-2,3-dihydrobenzofuran-5-oxyl radical compared with the 2,6-ditert-butyl-4-methoxyphenoxyl radical is attributed to entropy differences between the parent phenols.