Key Concepts In Organic Chemistry: Amines
-Amines have the general formula R N: where R = H, R or Ar. Each N atom in a molecular formula adds
1H to the saturated formula, thus, C H n 2n+2+Y y Always subtract 1H for each N atom in the molecule.
-Alkyl amines are often classified as 1° (primary), 2° (secondary), 3° (tertiary) or 4° (quaternary) amines,
depending on the number of C atoms bonded to the N atom. In normal 1°, 2° and 3° amines the electron
pair rapidly interconverts at room temperature so that enantiomers cannot be isolated (N atoms do not
normally act as stereocentres). In contrast, quaternary ammonium salts which have N atoms bonded to
four different groups are chiral (exist as two non-interconverting enantiomers).
-The names of the alkyl substituents are in alphabetical order before the word “amine” when naming
amines. When naming an NH substit2ent on a given compound, it is named “amino.” Organic
compounds that contain small amounts of N (weak bases) were known as alkaloids.
-Though the N-H bond in amines are polar and there intermolecular bonding observed in 1° and 2°
amines, the H-bonds are weaker than in alcohols because of the reduced electronegativity in nitrogen in
comparison to oxygen. Because amines have correspondingly strong conjugate acids, amines are