Transcript Functional Groups

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Give the molecular formula for each type of
hydrocarbon below if it contains seven carbon
atoms, draw one possible isomer and name
that isomer.
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A. An alkane
B. An alkene
C. An alkyne
Functional Groups
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A functional group is an atom or group of atoms that is
responsible for the specific properties of an organic
compound
A given functional group undergoes the same types of
chemical reactions in every molecule in which it is
found.
Therefore, compounds that contain the same functional
group can be classified together.
The general formula for a class of organic compounds
consists of the functional group and the letter R, which
stands for the rest of the compound.
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Alcohols are organic compounds that contain
one or more hydroxyl groups.
The general formula for alcohols if R-OH
H OH
 Example: ethanol
H—C—C—H
H H
Alcohols are often used as alternative fuels,
ethanol for example.
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Alcohols can be classified by the number of
carbons bonded to the carbon which holds the
hydroxyl group.
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Primary alcohols have 1 carbon bonded to the
alcohol carbon. Example—1-propanol
Secondary alcohols have 2 carbons bonded to the
alcohol carbon. Example—2-propanol
Tertiary alcohols have 3 carbons bonded to the
alcohol carbon. Example—2-methyl-2-butanol
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The name of the alkane chain loses the -e and
adds –ol.
A number is used to indicated the carbon
position of the hydroxyl group.
If more than one hydroxyl group is present, use
the ending, -diol, -triol, etc.
Name: H3C-CHOH-CHOH-CH3
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Alkyl halides are organic compounds in which
one or more halogen atoms, fluorine, chlorine,
bromine, or iodine, are substituted for one or
more hydrogen atoms in a hydrocarbon.
Since X is often used to represent a halogen, the
general formula for alkyl halides is R-X
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Chlorofluorocarbons, better known as CFC’s
have been used in the past as liquid
refrigerants and in aerosol cans.
These were found to deplete the ozone because
they would react with O3 and convert it to
diatomic oxygen, O2.
Another alkyl halide is Teflon. C2F4 is joined in
long chains to make the Teflon coating. It has a
low coefficient of friction which makes it ideal
for a “non-stick” coating.
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You have already learned how to name alkyl
halides.
Halogenated Hydrocarbons Worksheet
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Ethers are organic compounds in which two
hydrocarbon groups are bonded to the same
atom of oxygen. The hydrocarbon groups may
be the same or different.
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The general formula is R—O—R’.
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Example: CH3—O—CH3 Dimethyl ether
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Ethers are often used as organic solvents since
they are relatively unreactive.
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Simply name the two hydrocarbon groups then
add the term ether.
What would be the formula for methyl ethyl
ether?
What would be the name of H3C-CH2-CH2-OCH2-CH2-CH3?
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Do the first 7 rows of the Functional Groups
Worksheet
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Finish first 7 rows of Functional Groups
Worksheet
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Read Text 733-734
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Text 734 #1-5
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Write the general formula for the following and
give one example of each:
a) alcohol
b) ether
c) alkyl halide
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Aldehydes and ketones contain the carbonyl
group.
Aldehydes have the carbonyl group attached to
a carbon atom at the end of a chain.
Ketones have the carbonyl group attached to
carbon atoms within the chain.
General Formula for Aldehydes and Ketones
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Aldehydes and ketones are often responsible
for odors and flavors.
See Figure 14 Page 733
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Since the carbonyl group is always attached to
the 1st carbon, we do not use numbers to
indicate the position of the carbonyl group
when naming aldehydes.
Drop the ending –ane, -ene or -yne from the
hydrocarbon and add –al
What is the structural formula for butanal?
Name this one
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Drop the –e from the parent chain and add
-one.
You must use a position number for the
carbonyl group.
Carbonyl groups have priority for numbering.
What is the structure for 2-hexanone?
Name this one:
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Amines are organic compounds that can be
considered to be derivatives of ammonia, NH3.
Because the ammonia atoms have an unshared
electron pair, they will act as weak bases in
aqueous solutions.
The general formula is R-N-R”
R’
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Primary Amines—drop the –e of the parent chain,
add –amine.
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Secondary Amines—drop the –e of the parent
chain, add amine. Use N-to designate that the
second alkyl group is present on the nitrogen
atom.
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Example: 2-propanamine
Example: N-methyl-1-propanamine
Tertiary Amines are named like secondary, but use
two N’s to designate the second and third alkyl
group.
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Example: N, N-dimethylpropanamine
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Carboxylic acids are organic compounds that
contain the carboxyl functional group.
General Formula
Carboxylic acids, like inorganic acids, react to
lose a H+ and become negatively charged in
water.
They are weak acids.
Acetic acid is a carboxylic acid as is the citric
acid found in many fruits.
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Since the carboxyl group is always at the end of
the chain, there is no need to indicate the
position number of the group. It is always on
the 1st carbon.
Drop the ending –e and add –oic acid.
What would be the structure for butanoic acid?
Name this one:
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Esters are organic compounds that have
carboxylic acid groups in which the hydrogen
of the hydroxyl group has been replaced by an
alkyl group.
General Formula
Esters are derivatives of carboxylic acids.
Many occur naturally in fats and oils.
Low molecular weight esters are found in
essential oils and pheremones.
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First name the part that is the alkyl group, then
the acid using an –oate ending.
What would be the structure for methyl
propanoate?
Name this:
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Complete the rest of the table.
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Finish Functional Groups Worksheet
Complete Practice with Functional Groups
Worksheet #1-8
Functional Groups Quiz—Friday 5/28