The
reaction of an aromatic amine (e.g. aniline)
with nitrous acid at low temperatures
(below 5°C).
C6H5NH2 + HNO2 → C6H5N+N + OH-
+ H2O
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.
