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You are using Science Of Synthesis as a Guest. Please login or sign up for a free trial to access the full content. Method 3: Nitrogen-Substituted Benzo-1,4-quinones by Oxidation of a Benzene Ring

DOI: 10.1055/sos-SD-028-00071

Lee, H.; Theodorakis, E. A.Science of Synthesis, (20062875.

Several oxidative methods have been explored for the conversion of nitrogen-substituted arenes into the corresponding benzoquinones. Four different classes of starting materials undergo such reactions: the first includes nitrogen-substituted phenols, such as the hydroxylated amide 18 (Scheme 7). Here the oxidation is best performed with Fremy's salt (potassium nitrosodisulfonate)[‌20‌,‌21‌] which affords the benzo-1,4-quinone 19 in 90% yield,[‌20‌] although in other cases autooxidation may occur.[‌22‌]

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