Photochemical versus aluminium chloride-catalyzed fries rearrangement of aryl hydrogen succinates. synthesis of 2(3H)-furanones

The photochemical and aluminium chloride-catalyzed Fries rearrangement of a series of aryl hydrogen succinates3 a–f to the corresponding 4-oxoacids1 a–f are compared. Both approaches are complementary: the photochemical process is more general and becomes the method of choice for the succinoylation of phenols supporting alkoxy or hydroxy substituents, while the classical rearrangement is superior in the presence of alkyl or halogen substituents. These results are applied to the preparation of the 2(3H)-furanones2 a–f.