Fries Rearrangement
Phenyl esters ( phenyl acetate,phenyl benzoate etc.) on heating with anhydrous AlCl3 in the presence of CS2 as solvent undergo a rearrangement in which the acyl group (acetyl , benzoyl etc. ) group migrates from the phenolic oxygen atom to the ortho and para position of the benzene ring to give a mixture of o and p hydroxy ketones. this reaction is called fries rearrangement.
