2. Functional Groups
Part of an organic molecule where
chemical reactions take place
Composed of an atom or group of atoms
Replace a H in the corresponding alkane
Provide a way to classify organic
compounds
2
3. Some Types of Functional Groups
Haloalkane
-F, -Cl, -Br CH3Cl
Alcohol
-OH
CH3OH
Ether
-OO
CH3-O-CH3
C H
CH3CH
Aldehyde
Ketone
O
O
O
C
CH3CCH3
3
5. Haloalkanes
An alkane in which one or more H atoms is
replaced with a halogen (F, Cl, Br, or I)
CH3Br
1-bromomethane
Br
(methyl bromide)
CH3CH2CHCH3
2-bromobutane
Cl
chlorocyclobutane
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7. Solution HA1
Name the following:
Br
bromocyclopentane
Cl
1,3-dichlorocyclohexane
Cl
7
8. Substituents
List other attached atoms or group in
alphabetical order
Br = bromo, Cl = chloro
Cl
Br
CH3CHCH2CHCH2CH2CH3
4-bromo-2-chloroheptane
8
9. Learning Check HA2
The name of this compound is:
Cl
CH3
CH3CH2CHCH2CHCH3
1)
2,4-dimethylhexane
2)
3-chloro-5-methylhexane
3)
4-chloro-2-methylhexane
9
10. Solution HA2
The name of this compound is:
Cl
CH3
CH3CH2CHCH2CHCH3
3) 4-chloro-2-methylhexane
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11. Haloalkanes as Anesthetics
Halothane (Fluothane)
F Cl
F
C
C
Br
F
H
Fluothane is a haloalkane that is widely used
as an anesthetic, which is a compound that
decreases the ability of the nerve cells to
conduct pain.
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13. Chlorofluorocarbons (CFCs
and the Ozone Layer
ozone O3 layer absorbs most of the
sun’s harmful radiation.
CFCs - chlorofluorocarbons - are
depleting that ozone layer.
CFCs are used as Freons in
refrigeration,
air conditioning, and foam insulation.
Their use in spray cans is no longer
allowed.
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14. Chlorofuorocarbons and the
Ozone Layer
In the stratosphere, the CFCs react with
the high-energy UV radiation from the sun
CF2Cl2
Freon-12
UV light
CF2Cl• + Cl•
free radical
14
15. Chlorofuorocarbons and the
Ozone Layer
To become stable, the Cl• acquires an electron
from ozone O3 and produces ClO.
Cl•
+
O3
ClO + O2
The presence of ClO in the atmosphere is an
indicator of the disappearance of ozone.
15
16. Impact of Loss of Ozone Layer
According to the National Academy of
Sciences, each 1% loss of ozone increases
by 2% the amount of UV radiation reaching
the earth. More UV radiation means more
skin cancer and cataracts in humans, more
intense photochemical smog, and lower crop
yields.
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