1. Alcohols Contain a hydroxyl (-OH) group− +
Intermolecular forces: dipole-dipole, H-bonding
H-bonds between alcohol molecules: high boiling points
H-bonds with water: up to 4-carbon alcohols soluble in water
-OH group can act as a weak base or a weak acid
+ Strong base
+ Strong acid
alkoxide
alcohol
oxonium ion

2. Alcohol Nomenclature
Parent chain = longest chain containing C with -OH
Root name: replace –e with –ol
ethane  ethanol, butene  butenol, etc.
Give –OH the smallest possible number
–OH has priority over double bonds, alkyl groups
Two –OH groups  -diol; three –OH groups  -triol
Add to end of root name (propane  propanediol)
1,2-ethanediol
(ethylene glycol)
antifreeze
5-methyl-3-hexanol

3. Alcohol Naming Practice
2-propanol
(isopropyl alcohol)
2,4-dimethyl-3-pentanol
3,5-dimethyl-2,4-heptanediol
4-penten-2-ol

4. Classes of Alcohols Primary (1°) alcohol 1-butanol
OH C attached to 1 other C
Secondary (2°) alcohol
OH C attached to 2 other C’s
4-phenyl-2-hexanol
Tertiary (3°) alcohol
OH C attached to 3 other C’s
1-methylcyclohexanol

5. Reactions of Alcohols Reaction with strong bases
alcohol as proton donor (weak acid)
Reaction with strong acids
alcohol as proton acceptor (weak base)
Dehydration
reverse of hydration of alkenes
requires H+ catalyst
Oxidation
increase # of C-O bonds
alkoxide
Strong acid
oxonium ion H+
- H2O
alkene
oxidizing agent or
aldehyde
ketone

6. Dehydration Mechanism
Step 1: electrophilic H+ catalyst attacks nucleophilic O atom
Step 2: H2O dissociates, leaving behind a carbocation +
H2O
Step 3: Electrons from neighboring C-H bond form  bond, regenerating H+ catalyst +

7. Hydration and Dehydration+
H2O
Hydration and dehydration are in equilibrium
Can change [H2O] to favor one reaction or the other
Change
Favors
Increase [H2O]
Formation of Alcohol (hydration)
Decrease [H2O]
Formation of Alkene (dehydration)

8. Possible Dehydration Products?
Major
product
Least H’s on double bond
The most-substituted alkene product is favored (most stable)

9. Oxidation of Alcohols Oxidation: increases oxidation number
More C-O bonds (add O) or increases bond order
Fewer C-H bonds (remove H)
Needs an oxidizing agent
CrO3, Cr2O72-, MnO4-
,or PCC (pyridinium chlorochromate)
PCC stops at
aldehyde
1° alcohol +1 -2 -2 -2 -1
oxidizing
agent
oxidizing
agent +1 +3 +1 -2 +1 +1 +1
aldehyde
carboxylic acid
CrO3
(Cr6+)
Cr3+

10. Breathalyzer Tests ethanol ethanal ethanoic acid + Cr6+ + Cr3+
oxidized
oxidized
ethanol
ethanal
(acetaldehyde)
ethanoic acid
(acetic acid)
+ Cr6+
+ Cr3+

11. Breathalyzer Tests ethanol ethanal ethanoic acid + Cr6+ + Cr3+
oxidized
oxidized
ethanol
ethanal
(acetaldehyde)
ethanoic acid
(acetic acid)
+ Cr6+
+ Cr3+
oxidized
oxidized
methanol
methanal
(formaldehyde)
methanoic acid
(formic acid)

12. Oxidation of Alcohols No reaction 2° alcohol 3° alcohol 2-propanol-2 +1
oxidizing
agent
2° alcohol +2 -2 +1
ketone
2-propanol
propanone
(acetone)
oxidizing
agent
3° alcohol
No reaction

13. Reaction of Alcohols with Hydrogen Halides
1° alcohols react via the SN2 reaction mechanism: C OH + HX C X + H2O 2° and 3° alcohols react via SN1 reaction mechanism: C C OH + HX C C X + H2O C C

14. Reaction of Alcohols with Hydrogen Halides
CH3OH + HBr CH3Br + H2O CH3CHCH3 + HCl CH3CHCH3 + H2O OH Cl

17. Naming aldehydes and ketones
Parent chain = longest chain containing C=O (carbonyl)
Aldehyde
Ketone
Prefix
Suffix
Numbering
oxo
–e becomes –al
C=O is always C #1
(don’t have to number it)
oxo
–e becomes –one
C=O is lowest possible number
(must number it)
Naming Priority: Aldehydes > Ketones > Alcohols
-OH (alcohol) substituent → “hydroxy”
3-hydroxy-4-methylpentanal
3-chloro-2-butanone

18. Has both an aldehyde and a ketone
Naming Practice
propanedial
2,4-pentanedione
Aldehyde has priority
Ketone = oxo
Has both an aldehyde and a ketone
3-oxopentanal

19. Condensation of Alcohols
Condensation reaction: two molecules combine to form a larger molecule (+ water)
Catalyzed by acid (H+)
H2SO4
catalyst
CH3−OH +
H-O−CH3
CH3−O−CH3 +
H2O
alcohol +
alcohol
ether +
water

20. Two alkyl groups (C’s) bound to oxygen
Ethers −
H-bond acceptor
No H-bond donor
water
alcohol
Two alkyl groups (C’s) bound to oxygen
Intermolecular forces:
Dipole-dipole
No H-bonding between ether molecules
Lower boiling point than alcohols
Water or alcohols can H-bond to ether oxygen
Somewhat soluble in water and other polar solvents

21. Naming Ethers Common names: name both R groups, add “ether”
diethyl ether
(anesthetic)
ethyl
ethyl

22. tert-butyl methyl ether
Naming Ethers
Common names: name both R groups, add “ether”
diethyl ether
(anesthetic)
ethyl
ethyl
tert-butyl methyl ether
(used as gasoline additive)
tert-butyl
methyl
propyl people ether
propyl
♫ “one-eyed, one-horned, flying...” ♪

25. diisopropyl ether peroxide
Reactions of Ethers
Formation of peroxides
peroxide + O2
diisopropyl ether
Explosive!
Reactions of peroxides:
diisopropyl ether peroxide
Controlled
detonation
Resulting crater:
3 feet wide,
one foot deep

26. Aldehydes and Ketones C=O group called a carbonyl group C and O both
sp2 hybridized
120°
120°
aldehyde
ketone
C=O group called a carbonyl group −
Very polar C=O bond
Higher boiling point than alkanes
H-bond acceptor
Soluble in polar solvents
No H-bond donor
Lower boiling point than alcohols +

27. (contain a double bond)
Structural Isomers
Draw all the possible structural isomers for the following formulas:
C4H10O
C5H12O
C4H8O
C5H10O
Alcohols and Ethers
Aldehydes and Ketones
(contain a double bond)
Notice that all formulas contain one oxygen
What functional groups do you know that contain one oxygen?
Does the atom ratio of carbon to hydrogen make a difference?

28. isopropyl methyl ether
C4H10O Isomers
1-butanol
2-butanol
2-methyl-2-propanol
2-methyl-1-propanol
diethyl ether
methyl propyl ether
isopropyl methyl ether

29. C5H12O Isomers 1-pentanol 2-pentanol 3-pentanol 2-methyl-1-butanol
2,2-dimethyl-1-propanol

30. C5H12O Isomers butyl methyl ether tert-butyl methyl ether
sec-butyl methyl ether
isobutyl methyl ether
ethyl propyl ether
ethyl isopropyl ether

31. C4H8O Isomers
butanal
2-butanone
2-methylpropanal

32. C5H10O Isomers pentanal 2-pentanone 3-pentanone 3-methylbutanal
3-methyl-2-butanone
2,2-dimethylpropanal
2-methylbutanal

33. Reactions of Aldehydes and Ketones
Oxidation of aldehydes to carboxylic acids
CrO3, MnO4-
Reduction of aldehydes and ketones to alcohols
Decrease C-O bonds, increase C-H bonds
Reducing agents: LiAlH4, NaBH4, H2/Pt
LiAlH4
propanal
1-propanol
CH3−CH2−CHO
CH3−CH2−CH2−OH
NaBH4
2-methyl-3-pentanone
2-methyl-3-pentanol

34. Reduction of Aldehydes/Ketones
LiAlH4
3-oxopentanal
1,3-pentanediol
NaBH4
cyclohexanone
cyclohexanol
H2/Pt
pentanedial
1,5-pentanediol

35. Carboxylic Acids Carboxyl group: -CO2H, -COOH−
H-bond acceptor
Carboxyl group: -CO2H, -COOH + − +
H-bond donor
Intermolecular forces: dipole-dipole, H-bonding
Pure carboxylic acids form hydrogen bonded dimers
very high boiling points (higher than alcohols)

36. Carboxylic Acid Nomenclature
Parent chain: longest containing carboxyl group (COOH)
Name of parent: replace “–e” with “–oic acid”
Numbering starts at carboxyl carbon
Priority: Carboxylic acid > aldehydes > ketones > alcohols 
“hydroxy” substituent
“oxo” substituents
3-oxobutanoic acid
(diabetes)
trans-3-methyl-2-hexenoic acid
(human armpits)
propanedioic acid
(apples)

37. Can irritate your stomach
aspirin
Tylenol
Can irritate your stomach
Gentle on the stomach
A carboxylic acid
Just an alcohol

38. Carboxylic Acid Reactions
Reduction to 1° alcohols
Only LiAlH4 reduces carboxylic acids
(not NaBH4 or H2/Pt)
LiAlH4
butanoic acid
1-butanol
NaBH4
butanoic acid
NO RXN
or H2/Pt
Reactant remains unchanged

39. What are the products? 3-oxo-4-pentenoic acid 3-hydroxypentanoic acid
H2/Pt
NaBH4
LiAlH4
3-hydroxypentanoic acid
3-hydroxy-4-pentenoic acid
4-pentene-1,3-diol