Uncatalyzed reductive fission of azoarenes to aminoarene(s) by hydrazine hydrate

Various azoarenes with hydrazine hydrate in refluxing ethanol undergo reductive fission to give easily isolable arninoarene(s) without use of any specialized catalyst. The reaction is fast and cost effective, and yields are excellent (85-95%). Substituents such as -OH, -OCH3. -COOH, -Cl, and -Br are unaffected. The method affords an elegant route to the preparation of arninoarenes.