General

What is the IUPAC convention for naming amines?

1. For terminal amines (1$^{o}$ amines), identify the alkane and add the suffix $-amine$.
2. For 2$^{o}$ and 3$^{o}$ amines, identify the alkane chains and arrange with the shorter alkane first followed by the longer alkane and amine.
   • If the alkane chains are the same, use di- or tri-.

     Figure 52.2: Amine nomenclature and the number of alkane chains: (left) 2-methyl-1-propanamine, (center) diethylamine, (right) trimethylamine.

     

3. If the amine group is an $-NH_{2}$ group, use the prefix ``amino''.
   • ``Amino'' prefixes are often used when a molecule has an $-OH$ or $-CO_{2}H$ group:

     Figure 52.3: Amine nomenclature and using the amino prefix: aminomethanol (left) and 2-aminoethanol (right).

     

What is the stereochemistry and hybridization of amines and the nitrogen atom?

The amine geometry is trigonal pyramidal, the bond angles are tetrahedral, and the nitrogen is $sp^{3}$ hybridized:

Figure 52.4: Amine stereochemistry and hybridization: trigonal pyramidal stereochemistry with tetrahedral bond angles and an $sp^{3}$ hybridized nitrogen.

What can occur to amines because they are $sp^{3}$ hybridized?

They can ``flip'', i.e. undergo an interconversion between amine enantiomers:

Figure 52.5: Amine enantiomers.