Arylamines Aniline Diazonium salts

Aniline is a primary arylamine, and it reacts with nitrous HNO2 to yield stable benzene diazonium salt (Ph—N+=NX ). 

Arylamines that contain an acid group (sulfo or carboxyl) are diazotized by the so-called indirect method . They are dissolved in aqueous alkali, treated with a solution of the calculated amount of sodium nitrite, and dropped into an excess of acid the diazonium salt then usually separates as a solid. This method has been used with success for diazotizing aminobenzoic acid and aniline- and naphthylamine-sulfonic acids weakly basic amines such... 

Aniline, 407, 859. See also Arylamines Diazonium salts basicity of, 866—868 electrostatic potential map, 862 isolation, 859... 

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