1. Amines
Amines are organic derivatives of ammonia, in which one, two, or all three
of the hydrogens of ammonia are replaced by organic groups.
Amines are categorized by the number of alkyl groups attached to nitrogen:
For example:

2. "Physical Properties"
Like ammonia, low-molecular-weight amines have very
sharp penetrating odors.
Primary and secondary amines can H-bond with themselves,
so have relatively high boiling points.
However, because the N-H bond is less polar than the O-H
bond, amines have lower boiling points than alcohols.
Tertiary amines can’t H-bond with themselves, and so have
boiling points near those of ethers and hydrocarbons.
Smaller amines (less than 5 carbons) are soluble in water.
primary and secondary amines are more soluble than tertiary
because they have more H-bonding with water.

3. "Chemical Properties"
Like ammonia, primary, secondary and tertiary amines have a
single pair of electrons on N atom. Hence chemical behavior of
amines is similar to ammonia. Amines are basic in nature, and
in most of the reactions they act as nucleophiles.
"Basicity of amines"
The greater the availability of the lone pair electrons on
nitrogen, the greater the base.
pKb was a measure of base strength.
Kb = [RNH3+] [OH-] / RNH2
pKb = - log Kb
The stronger the base the lower the pKb
Effect on amine basicity ( inductive effect – Alkyl substitution)
pKb 3.36
3.28
Methyl group increases Electron
density on N atom thus (dimethyl
amine) more basicity than (methyl
amine).
WATCH OUT THREE METHYL GROUPS DECREASES
BASICITY pKb = 4.26 - Steric inhibition of solvation of
HOH with the NH+ of the R3NH+ cation.

4. "Preparation of amine"
1-Ammonia by alkylation with alcohols:
ROH + NH3 → RNH2 + H2O
2- Ammonolysis of alkyl halides
3- Reduction of nitriles:
4- Reduction of nitro compounds:

5. "Biological activity"
Many drugs are designed to mimic or to interfere with the
action of natural amine neurotransmitters, exemplified by
the amine drugs:
1- Chlorpheniramine is an antihistamine that helps to relieve
allergic disorders due to cold, hay fever, itchy skin, insect
bites and stings.
2- phenylephrine, as amine hydrochlorides, are used as
decongestants

6. 3- Chlorpromazine is a tranquillizer that sedates without
inducing sleep. It is used to relieve anxiety, excitement,
restlessness or even mental disorder.
4- Sympathomimetic drugs mimic the effects of transmitter
substances of the sympathetic nervous system such as
epinephrine (adrenaline) , norepinephrine (noradrenaline) ,
dopamine. Such drugs are used to treat cardiac arrest and
low blood pressure, or even delay premature labor, among
other things
epinephrine (adrenaline)
norepinephrine (noradrenaline)

7. dopamine