Download Oxygen containing organic compound

What are alcohols?
An alcohol contains a
hydroxyl group (—OH)
attached to a carbon
chain.
water
A phenol contains a
hydroxyl group (—OH)
attached to a benzene
ring.
alcohol
phenol
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How do we name alcohols?
Formula
IUPAC Name
CH4
methane
CH3─OH
methanol
CH3─CH3
ethane
CH3─CH2─OH
ethanol
The names of alcohols
• in IUPAC replace the
-e with -ol.
More names of alcohols
CH3─CH2─CH2─OH
1-propanol
OH
│
CH3─CH─CH2─CH3
2-butanol
• IUPAC names for
longer chains number
chain from
– end nearest -OH
group.
CH3
OH
│
│
CH3─CH─CH2─CH2─CH─CH3
5-methyl-2-hexanol
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5
4 3
2 1
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What are phenols?
Phenol
• IUPAC name for benzene with a
hydroxyl group.
• is used in antiseptics and disinfectants.
OH
OH
OH
OH
OH
CH2CH2CH2CH2CH2CH3
phenol
resorcinol
4-hexylresorcinol
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Derivatives of Phenol
Compounds of phenol are the active
ingredients in the essential oils of cloves,
vanilla, nutmeg, and mint.
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How to name a phenol!
To name a phenol
•with two substituents, assign C-1 to carbon
attached to –OH.
•Number ring to give lowest numbers.
OH
OH
1
1
3
Cl
4
Br
3-chlorophenol
4-bromophenol
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Classification of alcohols
• determined by number of alkyl groups attached to
carbon bonded to hydroxyl.
• primary (1°), secondary (2°), or tertiary(3).
Primary (1º)
1 group
H
|
CH3—C—OH
|
H
Secondary (2º)
Tertiary (3º)
2 groups
3 groups
CH3
|
CH3—C—OH
|
H
CH3
|
CH3—C—OH
|
CH3
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What are ethers?
An ether
• contains an ─O─ between two carbon groups.
• has a common name that gives alkyl names of
attached groups followed by ether.
CH3─O─CH3
CH3─CH2─O─CH3
dimethyl ether
ethyl methyl ether
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Ethers as anesthetics
Anesthetics
• inhibit pain signals to the brain.
• like diethyl ether CH3─CH2─O─CH2─CH3 were used
for over a century, but caused nausea and were
flammable.
• developed by the 1960’s were nonflammable.
Cl F
F
Cl F
H
│ │
│
│ │
│
H─C─C─O─C─H
H─C─C─O─C─H
│ │
│
│ │
│
F F
F
H F
H
Ethane(enflurane)
Penthrane
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Now let’s look at the
Properties of Alcohols and Ethers,
Alcohols
•contain polar OH groups.
•form hydrogen bonds with other alcohol
molecules.
•have higher boiling points
than alkanes and ethers of similar mass.
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However ethers…………
Ethers
• do not have a polar
group.
• have an O atom,
but there is no H
attached.
• cannot form
hydrogen bonds
between ether
molecules.
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Solubility of alcohols and ethers in water
Alcohols and ethers
• are more soluble in water than alkanes because the
oxygen atom can hydrogen bond with water.
• with 1-4 C atoms are soluble, but not with 5 or
more C atoms.
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Reactions of alcohols are…
Alcohols undergo combustion with O2 to produce
CO2 and H2O.
2CH3OH + 3O2
2CO2 + 4H2O + Heat
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Dehydration of Alcohols
Alcohols undergo
• dehydration when heated with an acid catalyst.
• the loss of —H and —OH from adjacent carbon
atoms.
H OH
|
|
H+, heat
H—C—C—H
H—C=C—H + H2O
|
|
| |
H H
H H
alcohol
alkene
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Oxidation vs Reduction
In an oxidation,
• there is an increase in the number of C-O bonds.
• there is a loss of H.
In a reduction,
• there is an decrease in the number of C-O bonds.
• there is a gain of H.
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Oxidation of primary (1) alcohols
When a primary alcohol is oxidized, [O],
• one H is removed from the –OH.
• another H is removed from the carbon bonded to the OH.
• an aldehyde is produced.
[O]
Primary alcohol
Aldehyde
OH
O
|
[O]
||
CH3—C—H
CH3—C—H + H2O
|
H
Ethanol
(ethyl alcohol)
Ethanal
(acetaldehyde)
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Oxidation of secondary (2) alcohols
When a secondary alcohol is oxidized, [O],
• one H is removed from the –OH.
• another H is removed from the carbon bonded to the OH.
• a ketone is produced.
secondary alcohol
OH
│
CH3─C─CH3
│
[O]
[O]
ketone
O
║
CH3─C─CH3 + H2O
H
2-propanol
2-propanone
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Oxidation of tertiary ( 3)alcohols
Tertiary 3alcohols do not readily oxidize.
[O]
Tertiary alcohol
no reaction
OH
│
[O]
CH3─C─CH3
no product
│
CH3
no H on the C-OH to oxidize
2-methyl-2-propanol
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Oxidation of Ethanol in the Body
In the body,
• enzymes in the liver oxidize ethanol.
• aldehyde product impairs coordination.
• blood alcohol over 0.4% can be fatal.
O
O
║
║
CH3CH2OH
CH3CH
CH3COH
2CO2 + H2O
ethyl alcohol
acetaldehyde
acetic acid
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Ethanol CH3CH2OH
Ethanol
• acts as a depressant.
• kills or disables more
people than any other drug.
• is metabolized at a rate of
12-15 mg/dL per hour
by a social drinker.
• is metabolized at a rate of
30 mg/dL per hour
by an alcoholic.
% Ethanol
50%
40%
15-25%
12%
3-9%
Product
Whiskey, rum, brandy
Flavoring extracts
Listerine, Nyquil, Scope
Wine, Dristan, Cepacol
Beer, Lavoris
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What do Aldehydes and Ketones
have in common?
A carbonyl group
• in an aldehyde is
attached to at least
one H atom.
• in a ketone is
attached to two
carbon groups.
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More examples!
O
C
H
Benzaldehyde (almonds)
O
CH=CH C
H
Benzaldehyde (almonds)
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How to name ketones
In naming ketones
• as IUPAC, -e in alkane name replaced with –one.
• With a common name, alkyl groups attached to
carbonyl group are named alphabetically followed
by ketone.
O
O
║
║
CH3 ─C─CH3
CH3─C─CH2─CH3
propanone
2-butanone
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Are they soluble? aldehydes and ketones
• electronegative O atom of carbonyl group
•aldehydes and ketones
•hydrogen bonds with water
•not between each other, thus
•higher boiling points
•alkanes and ethers of similar mass.
•lower boiling points
•alcohols of similar mass.
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Reactions of aldehydes


Aldehydes oxidize readily to carboxylic acids.
Ketones do not oxidize further
O
||
CH3—C—H 
oxidation
O
||
CH3—C— CH3-------
oxidation
O
||
CH3—C—OH
NO REACTION
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