Detection of intermediates and isolation of hydroquinone monoacetate in the Dakin oxidation of p-hydroxyacetophenone

Oxidation of o-, m-, and p-hydroxyacetophenone with peracetic acid or tert-butyl hydroperoxide, oxidants relatively readily monitored by nmr, failed to generate isolable intermediates though an intermediate was detected for the p-ketone. Attempted oxidation of a number of related ketones under Dakin conditions failed either to react, or to generate a detectable intermediate. However, with delicate adjustment of pH and careful timing of the isolation procedure, hydroquinone monoacetate has for the first time been successfully isolated from an alkaline aqueous hydrogen peroxide oxidation (Dakin oxidation) of p-hydroxyacetophenone.