Amine

In chemistry, amines (/əˈmiːn, ˈæmiːn/, UK also /ˈeɪmiːn/) are organic compounds that contain carbon-nitrogen bonds. Amines are formed when one or more hydrogen atoms in ammonia are replaced by alkyl or aryl groups. The nitrogen atom in an amine possesses a lone pair of electrons. Amines can also exist as hetero cyclic compounds. Aniline (${\displaystyle {\ce {C6H5NH2}}}$) is the simplest aromatic amine, consisting of a benzene ring bonded to an amino (–${\displaystyle {\ce {NH2}}}$) group.

Amines are classified into three types: primary (1°), secondary (2°), and tertiary (3°) amines. Primary amines (1°) contain one alkyl or aryl substituent and have the general formula ${\displaystyle {\ce {RNH2}}}$. Secondary amines (2°) have two alkyl or aryl groups attached to the nitrogen atom, with the general formula ${\displaystyle {\ce {R2NH}}}$. Tertiary amines (3°) contain three substituent groups bonded to the nitrogen atom, and are represented by the formula ${\displaystyle {\ce {R3N}}}$.

The functional group −NH₂ present in primary amines is called the amino group.