The ethylene acetals of o and p-acetoxyacetophenone 3a, b, prepared from the corresponding hydroxyacetophenones by treatment with acetic anhydride in pyridine and subsequently with ethylene glycol and p-toluenesulphonic acid, give upon irradiation the expected photo-Fries products 4a, b (from 3a) or 6 (from 3b). These compounds are converted in part into diacetylphenols 5a, b as a consequence of a deacetalization, ...
