Question

What are amines? How are they classified?

Answer 1

Amines are organic derivatives ofammonia, NH3, in which one or more of the three H's is replaced by a carbon group. Amines are classified as primary (1°), secondary (2°), or tertiary (3°), depending on how many carbon groups are connected to the nitrogen atom.Nitrogen-Containing Functional Groups
• Nitrogen is in Group V of the periodic table, and in
most of its compounds, it has three single bonds and
one lone pair:
• In this chapter, we will take a look at two functional
groups which contain nitrogen atoms connected to
carbons: the amines and the amides.
R C
O
N
R"
R'
Amide
R R'' N
R'
Amine
N
3
Classification and
Nomenclature of Amines
4
Amines
• Amines and amides are abundant in nature. They
are a major component of proteins and enzymes,
nucleic acids, alkaloid drugs, etc. (Alkaloids are N-
containing, weakly basic organic compounds;
thousands of these substances are known.)
• Amines are organic derivatives of ammonia, NH3, in
which one or more of the three H’s is replaced by a
carbon group.
• Amines are classified as primary (1°), secondary
(2°), or tertiary (3°), depending on how many
carbon groups are connected to the nitrogen atom.
R R'' N
R'
3° Amine
R H N
H
1° Amine
R H N
R'
2° Amine
H H N
H
Ammonia
5
Examples: Classifying Amines
• Classify the following amines as primary (1°),
secondary (2°), or tertiary (3°).
CH3CH2CH2 N
H
H CH3 N
CH3
CH3 CH3CH2CHCH3
NH2
CH3CH2 N
H
CH3 N
H
N
6
Nomenclature of Amines
• Simple 1°, 2°, and 3° amines: common (trivial)
names are obtained by alphabetically arranging the
names of the alkyl substituents on the nitrogen and
adding the suffix -amine (e.g., ethylmethylamine).
• Amines in the IUPAC system: the “e” ending of
the alkane name for the longest chain is replaced
with –amine. The amine group is located by the
position number. Groups that are attached to the
nitrogen atom are located using “N” as the position
number. More complex primary amines are named
with —NH2 as the amino substituent.
• Aromatic amines: named as derivatives of the
parent compound aniline. Substituents attached to
the nitrogen are indicated by using “N-”