Boyland–Sims oxidation

The Boyland–Sims oxidation is the chemical reaction of anilines with alkaline potassium persulfate, which after hydrolysis forms ortho-hydroxyl anilines.

The ortho-isomer is formed predominantly. However, the para-sulfate is formed in small amounts with certain anilines.

Behrman has shown that the first intermediate in the Boyland–Sims oxidation is the formation of an arylhydroxylamine-O-sulfate (2). Rearrangement of this zwitterionic intermediate forms the ortho- sulfate (5), which then hydrolyses to form the ortho-hydroxyl aniline.

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