Imide

In organic chemistry, imide is a functional group consisting of two carbonyl groups bound to a primary amine or ammonia. Imides are generally prepared directly from ammonia or the primary amine, and either carboxylic acid(s) or acid anhydrides. The structure of the imide moiety is as shown to the left. Image:Imide small line.png

In chemical industry, many imides are monomers used to make polyimides. The imides most commonly used for this are based on aromatic dicarboxylic acids of moderately high molecular weight. Such imides contain a heterocyclic ring, shown to the right. Image:Heterocyclic imide.png Another important imide is phthalimide, the heterocyclic imide of phthalic acid. It is an intermediate in the preparation of phthalocyanine dyes. Some phthalimides have luminescent qualities.

Imide may also refer to the polyatomic ion NH^2-, which is a powerful base and will turn into ammonia in the presence of water.