Photochemical reactions. Part 23. The photo-Fries rearrangement of bis-(2-acetylaminophenyl) disulphides

Abstract

Ultraviolet irradiation of the bis-(2-acetylaminophenyl) disulphides (1 a and b) results in the preferential formation of 7-(2-acetylaminophenylthio)benzothiazoles (2a and b) accompanied by minor amounts of 2-methylbenzothiazoles (3a and b), respectively. A crossover experiment with (1 a and b) clearly indicates that the formation of (2a and b) involves an intermolecular photo-Fries rearrangement.