Treatment of the p-quinols 2,6-di-t-butyl-4-hydroxy-4-phenylnaphthalen-1(4H)-one, 2,6-di-t-butyl-4-hydroxy-4-phenylcyclohexa-2,5-dienone and 2,6-di-t-butyl-4-hydroxy-4-(4'-methoxyphenyl)cyclohexa-2,5-dienone with acetic anhydride and sulfuric acid affords, as the major product, an aromatic ortho diol diacetate.