A product that the substitution of one or more hydrogen atoms in an ammonia molecule is replaced by a hydrocarbon group is called an amine. The compound formed after hydrogen in an ammonia molecule is replaced by a hydrocarbon group. An amine can be seen as a derivative of H in an ammonia molecule replaced by a hydrocarbon group. Amines widely exist in nature; have very important physiological activity and biological activity. For example, many proteins, nucleic acids, hormones, antibiotics, and alkaloids are amine complex derivatives. Most of the drugs used in clinical are the amine or amine derivatives. Amines have many uses. The earliest dyestuff industry was based on aniline. Some amines are necessary to maintain life activities, but some are very harmful to life. Many amines have carcinogenic effects, especially aromatic amines, such as naphthylamine and diphenylamine.
Amine has alkaline, and under the condition of the gas phase, ammonia is weaker than any kind of methylamine. But in the solution, its alkaline is similar to trimethylamine
. The alkaline of a methylamine and dimethylamine
is about 10 times stronger than trimethylamine. The lower amines are gases or volatile liquids that smell like ammonia and some have a fishy smell (the fishy smell actually comes mainly from trimethylamine). Higher amines are solids; Aromatic amines are mostly high boiling liquid or low melting solid with the special smell. The boiling point of amine is higher than that of non-polar compounds with similar molecular weight and lower than that of alcohol or carboxylic acid. The boiling point of the tertiary amine is lower than that of primary amine and secondary amine with similar molecular weight. Amines are polar compounds. Low - grade amine is soluble in water, and the amine is soluble in organic solvents such as alcohol, ether, and benzene.