72205-84-6Relevant academic research and scientific papers
A Mechanistic Study of the Thermal Disproportionation Reaction of Quinone Monoketals
Capparelli, Michael P.,Swenton, John S.
, p. 5360 - 5364 (2007/10/02)
Thermolysis of quinone monoketals 1a-d at 180 deg C leads to disproportionation to the p-alkoxyphenols 2a-d and the carbonyl compounds derived from the alcohol moiety of the ketal.The thermolysis of 4,4-dimethoxy-2,5-cyclohexadienone (1a) followed first-order kinetics, and the rate of reaction decreased by a factor of 3.6 when the methoxy groups were replaced with methoxy-d3 groups.The suggested mechanism for the reaction involves reversible dissociation of 1a into a p-methoxyphenoxy-methoxy radical pair, followed by rate-controlling hydrogen atom transfer to give p-methoxyphenol and formaldehyde.Although 1a has a half-life of about 4 h at 180 deg C, the monoethylene glycol ketal of benzoquinone was recovered in > 90percent yield after heating for 24 h at the same temperature.Finally, acid-catalysed exchange of 3,3,6,6-tetramethoxy-1,4-cyclohexadiene with alcohols furnished a convenient route to quinone bisketals not obtainable in good yield via anodic oxidation.
Anodic Oxidation of 1,4-Dimethoxy Aromatic Compounds. A Facile Route to Functionalized Quinone Bisketals.
Henton, Daniel R.,McCreery, Richard L.,Swenton, John S.
, p. 369 - 378 (2007/10/02)
The anodic oxidation of 12 functionalized 1,4-dimethoxybenzene derivatives and 8 functionalized 1,4-dimethoxynaphthalenes has been studied under a variety of conditions.Many substituted 1,4-dimethoxy aromatics afford high yields of the respective quinone bisketals by single-cell anodic oxidation without accurate control of the electrode potential.Oxidizable groups offen complicate the anodic oxidation; however, in some cases protected derivatives of these functionalities can be converted to the bisketals in good yields.Aromatics containing reducible functions can besmoothly oxidized to quinone bisketals by the use of a divided cell.The current efficiencies and the effect of electrode material on selected systems are reported and discussed.
