Redox‐Neutral Selenium‐Catalysed Isomerisation of para‐Hydroxamic Acids into para‐Aminophenols.

A selenium‐catalysed para‐hydroxylation of N‐aryl‐hydroxamic acids is reported. Mechanistically, the reaction comprises an N−O bond cleavage and consecutive selenium‐induced [2,3]‐rearrangement to deliver para‐hydroxyaniline derivatives. The mechanism is studied through both 18O‐crossover experiments as well as quantum chemical calculations. This redox‐neutral transformation provides an unconventional synthetic approach to para‐aminophenols. [ABSTRACT FROM AUTHOR]