This is an example
of electrophilic substitution reaction From the above reactions, it is clear that the diazonium salts are very
good intermediates for the introduction of –F, –Cl, –Br, –I, –CN, –OH,
–NO2 groups into the aromatic ring Aryl fluorides and iodides cannot be prepared by direct halogenation The cyano group cannot be introduced by nucleophilic substitution of
chlorine in chlorobenzene but cyanobenzene can be easily obtained
from diazonium salt