amine

Amines are organic compounds and a type of functional group that contain nitrogen as the key atom. Structurally amines resemble ammonia, wherein one or more hydrogen atoms are replaced by organic substituents such as alkyl and aryl groups. An important exception to this rule is that compounds of the type RC(O)NR2, where the C(O) refers to a carbonyl group, are called amides rather than amines. Amides and amines have different structures and properties, so the distinction is chemically important. Somewhat confusing is the fact that amines in which an N-H group has been replaced by an N-M group (M = metal) are also called amides. Thus (CH3)2NLi is lithium dimethylamide. Primary aromatic amines are used as a starting material for the manufacture of azo dyes. It reacts with nitric(III) acid to form diazonium salt which can undergo coupling reaction to form azo compound. As azo-compounds are highly coloured, they are widely used in dyeing industries, such as: Methyl orange, Direct brown 138, Sunset yellow FCF and Ponceau.