On the mechanism of the Elbs peroxydisulfate oxidation and a new peroxide rearrangement

Semiempirical calculations show that the intermediate formed by reaction between peroxydisulfate anion and the phenolate ion (the Elbs oxidation) is the species resulting from reaction of the tautomeric carbanion rather than the one resulting from attack by the oxyanion. This is confirmed by synthesis of the latter intermediate by reaction between Caroʹs acid dianion (peroxymonosulfate) and some nitro-substituted fluorobenzenes. This intermediate rearranges preferentially to give the phenol ortho-sulfate rather than the para-sulfate characteristic of the Elbs oxidation. This reaction of an arylperoxysulfate to give a phenol ortho-sulfate is a new rearrangement.