ABSTRACT
The photo-Fries rearrangement, analogous to the classical Lewis acid-catalyzed Fries counterpart, was first reported by Anderson and Reese in 1960.
The prototype for this reaction is the photochemical transformation of phenyl acetate (
) into
o
- and
p
-hydroxyacetophenone (
and
) (Scheme 1). Since the initial discovery, a number of variations have been devised, and the process has been extended to systems (
) such as aryl carbonates, carbamates, sulfonates, and sulfamates, as well as anilides, sulfonanilides, and sulfenanilides. Analogous 1,3-migrations in the corresponding enol derivatives (
) have been observed (Scheme 2). In this context, it should be mentioned that the so-called
photo-Claisen rearrangement
is closely related to the photo-Fries rearrangement; it is experienced by aryl ethers (instead of aryl esters) and follows an analogous mechanism.
