Amines

Description

Amines are compounds that contain a nitrogen atom singly bonded to one or more alkyl groups. Amines are derivatives of ammonia (NH₃), where one or more hydrogen atoms are replaced by alkyl groups (R), forming an ${\rm{N{-}R}}$ single bond.

Amines are classified as primary, secondary, or tertiary depending on the number of hydrogen atoms that are replaced with an R group. Using IUPAC naming conventions, simple primary amines are designated by naming the alkyl groups attached to the nitrogen and replacing the -ane ending with -anamine. If necessary, the position of the nitrogen is specified with a number. Secondary and tertiary amines are named for the longest alkyl chain on nitrogen; the remaining alkyl groups are preceded by N-. If the amine contains higher-priority substituents, the nitrogen-containing group is named as an amino substituent. Amine basicity varies on whether the amine is primary, secondary, or tertiary. Nitrogen is an electronegative atom that makes the amine capable of hydrogen bonding. This results in stronger intermolecular forces than those in other functional groups.

At A Glance

• Amines are compounds that contain a nitrogen atom singly bonded to one or more alkyl groups. They are designated as primary, secondary, or tertiary by how many R groups are bonded to the nitrogen.
• Amines are more basic than ammonia. In general, secondary amines are more basic than primary amines, which are more basic than tertiary amines. Amines are capable of forming hydrogen bonds with water and therefore have strong intermolecular forces that result in higher melting points, boiling points, and water solubility.