Definition
The
reaction of an aromatic amine (e.g. aniline)
with nitrous acid at low temperatures
(below 5°C).
C
6H
5NH
2 + HNO
2 → C
6H
5N
+N + OH
-
+ H
2O
The acid is prepared in situ by reaction between
nitric acid and sodium nitrite. The
resulting diazonium ion is susceptible to attack
by nucleophiles and provides a
method of nucleophilic substitution onto
the benzene ring.
