ESR, ENDOR and TRIPLE Resonance Studies on Radical Reactions of 1,4-Benzoquinone and 1,4-Hydroquinone in Alkaline Methanol and Liquid Ammonia

Article abstract of DOI:10.1002/mrc.1260280313

The relative signs and absolute values of the hyperfine coupling constants of different methoxy-1,4-benzoquinones were measured by ESR, ENDOR and TRIPLE resonance spectroscopy.Reactions of 1,4-benzoquinone and 1,4-hydroquinone with methanol took place in alkine methanol, giving rise to methoxy-substituted 1,4-benzoquinones.The same substitution reaction occured in a mixture of ammonia and methanol.The reactions depend on temperature and the alkali concentration.Coupling constants were assigned by the modified additivity relationship method.An extremely small linewidth of 0.014 G was measured in the ESR spectrum of deuterated 2,5-dimethoxy-1,4-benzoquinone.