Alcohols, Phenols, and Ethers

1

• Alcohols, Phenols, and Ethers
• Alcohol has an OH group (hydroxy) attached to
  a saturated alkane. General formula R-OH.
• Phenol has an OH group on a benzene ring.
• Ether a compound that has the functional group

2

• Naming Alcohols
• Step 1 Name the longest chain to which the OH
  group is attached. Use the alkane name of the
  chain, drop the e ending, and replace it with
  ol.
• Step 2 Number the longest chain to give the
  lowest number to the carbon with the OH.
• Step 3 Locate the OH position.
• Example

OH
CH3CH2CH2CHCH2CH3
6 5 4 3 2 1
3-hexanol
3

• Naming Alcohols, cont.
• Step 4 Locate and name any other groups
  attached to the longest chain.
• Step 5 Combine the name and location of other
  groups, the location of the OH, and the longest
  chain into the final name.
• Example

OH
CH3
CH3
CH3CH2CH2CHCHCH3
6 5 4 3 2 1
2,4-dimethyl-3-hexanol
4

p. 407
5

p. 407
6

• Classification of Alcohols

7

• Physical Properties of Alcohols, cont.
• The OH group can hydrogen bond between alcohol
  molecules leading to relatively high boiling
  points.
• Hydrogen bonding in pure ethanol

8

• Physical Properties of Alcohols
• The OH group is polar and capable of hydrogen
  bonding.
• This makes low molecular weight alcohols highly
  soluble in water.
• Hydrogen bonding in a water-methanol solution

9

• Physical Properties of Alcohols, cont.
• Larger alkanes have greater hydrophobic regions
  and are less soluble or insoluble in water.
• Water interacts only with the OH group of
  1-heptanol

10

• Alcohol Reactions
• The removal of water (dehydration) from an
  alcohol is an elimination reaction and produces
  an alkene.

11

p. 411
12

• Oxidation the removal of hydrogen atoms.

13

• Alcohol Reactions, cont.
• Primary alcohol oxidation
• Secondary alcohol oxidation

14

• Properties of Ethers
• Much less polar than alcohols.
• Low boiling and melting points because of the
  inability to hydrogen bond between molecules.
• More soluble in water than alkanes, but less
  soluble than alcohols.

15

• Hydrogen bonding of dimethyl ether (a) with
  water and (b) no hydrogen bonding in the pure
  state