1-Hydroxy-9-xanthenone (Ia) condenses with the acyl and arylsulfonyl chlorides in the presence of aluminum chloride to give 2-acylated-1-hydroxy-9-xanthenones(Table 11). The acyl, aroyl and benzenesulfonyl derivatives of Ia and of 1-hydroxy-3-methyl-9-xanthenone(Ii) undergo Fries migration of the acyl group under the influence of aluminum chloride to give the corresponding 2-acyl derivatives (Table 11). 1-(P-Naphthoyloxy)-4-benzoyloxy-9- ...