The Oxygen Transfer Reaction of 4-Acetylazoxybenzenes in Sulfuric Acid

Abstract

When the starting materials 4-acetyl-ONN- and -NNO-azoxybenzene(1α and 1β, respectively) were heated in 70/80% sulfuric acid, α/β isomerization and the Wallach rearrangement to 4-acetyl-4′-hydroxyazobenzene (2) were observed. However, neither the o-hydroxyazobenzene nor 4-acetyl azobenzene was detected in the reaction product. The isomerization of 1α was faster than that of 1β, demonstrating the higher themodynamic stability of the latter.