Reactivity of 4‐nitropyridine‐N‐oxide (II)): Substitution of the nitro‐group by hydroxyl)

Abstract
Whereas 4‐nitropyridine‐N‐oxide is very stable towards dilute solutions of acids in water, its nitro‐group can be replaced by hydroxyl in a quick reaction by treating this substance with an alkaline solution of hydrogen peroxide in water at a temperature not surpassing 50°. This remarkable substitution reaction proceeds also when other 4‐substituted derivatives of pyridine‐N‐oxide and 4‐nitropyridine are reacted with the same reagent.