Cerium reagents silica support

Like cerium(IV), iron(III) salts can oxidize electron-rich centers by single-electron transfer to form radicals [1]. Early applications were developed for the oxidation of aromatic compounds, which undergo C-C bond formation to dimeric products. Because of their electronic properties, methoxy substituted arenes 25 are most reactive. Iron(III) chloride supported on silica gel was the reagent of choice, since inter-and intramolecular coupling products 26 are obtained in excellent yields (Scheme 8)... 

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