diazonium compound
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Benzenediazonium cation.
A diazonium compound is a salt containing the cation (positive ion) group where R is an aryl group, made
by reacting a primary aromatic amide with
nitrous acid (see nitrogen). The sensitivity
of diazonium compounds to light is exploited in the diazo process or ozalid
process. They couple with phenols to give azo compounds. The aliphatic diazo
compounds have a related structure.