Oxidation of anthracene with cerium(IV) ammonium nitrate
The oxidation of anthracene with cerium(IV) ammonium nitrate appears to occur through an initial anthracene radical cation which is transformed into a transient anthrol nitrate. Homolysis of the oxygen–nitrogen bond of the anthrol nitrate furnishes the nitrite radical and a mesomeric anthrone radical. While the former attacks the initial ion radical with a concerted mechanism to yield anthrol nitrite, the latter undergoes dimerisation to bianthrone, addition of a nitrate radical to yield 9,10-dihydro-10-oxo-9-anthryl nitrate which subsequently disproportionates to anthraquinone and nitrous acid, and oxidation to the anthrone cation. This is attacked by a nucleophile to yield 10-methoxyanthrone or 10-acetoxyanthrone according to the solvent used.