SCH4U
Date: __________________
Alcohols
Alcohol
 An alcohol is an organic compound containing a hydroxyl group.
 Its’ general formula may be written as R – OH where R is an alkyl group or hydrocarbon chain.
Naming Alcohols
 To name an alcohol, “ol” is added to the suffix of the parent alkane.
 When an alcohol contains more than two carbon atoms a numbering system is used to identify the
position of the hydroxyl group.
 If the main chain contains branches all previous rules apply to name these branches. Remember the
main chain must contain the hydroxyl group.
 Many cyclic and aromatic compounds also have hydroxyl groups attached and are classified as cyclic
alcohols and aromatic alcohols respectively.
Name the following alcohols:
a.
b.
Draw the following alcohols:
a. 1,3-butanediol
b. 2,3-dimethyl-2-butanol
c.
1-methylcyclohexanol
Primary, secondary and tertiary alcohols
 An alcohol can be classified as primary, secondary or tertiary
 If the carbon containing the hydroxyl group bonds to one other
carbon atom it is primary; two other carbon atoms – secondary
and three carbon atoms – tertiary.
Properties of Alcohols
 The hydroxyl group in an alcohol is polar therefore hydrogen bonding occurs.
 “Like dissolves Like” therefore these molecules are soluble in other polar solvents. However, in long
chain alcohols the effect of hydrogen bonding is minimized due to long nonpolar hydrocarbon portions.
Therefore larger alcohols are good solvents for nonpolar molecules.
 Hydrogen bonding also gives alcohols a high boiling point when compared to their parent alkanes.
Reactions of Alcohols
1. Preparing Alcohols: Hydration Reactions
 Alkenes undergo addition reactions. When the reactant used along with the alkene is water, an
alcohol is produced.
 This reaction follows Markovnikov’s rule.
SCH4U
2.
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Date: __________________
Alcohols to Alkenes: Elimination or Dehydration Reaction
This type of reaction is essentially the reverse reaction of the one shown above.
Under certain conditions alcohols decompose into alkenes and water.
This type of reaction is catalyzed by concentrated sulfuric acid.
3. Combustion of Alcohols
 Like hydrocarbons, alcohols undergo combustion reactions to produce carbon dioxide and water (in
complete combustion)
Ethers


An ether is an organic compound containing two alkyl groups separated by an oxygen atom
The general formula may be written as R – O – R
Naming Ethers
 Add oxy to the prefix of the smaller carbon chain.
 Join this to the alkane name of the larger chain.
Name the following Ethers:
a. CH3- O – CH2 - CH3
b. CH3- CH2- O – CH2 – CH2 – CH3
Properties of Ethers
 Ethers do not contain hydroxyl groups therefore they cannot make hydrogen bonds. However the CO single bond creates a polar molecule.
 As a result of these intermolecular forces the boiling points of ethers are slightly higher then the
boiling points of hydrocarbons, but lower than alcohols.
 Good solvents for organic reactions because they dissolve polar and nonpolar substances.
Preparing Ethers from Alcohols: A condensation reaction
 Ethers form when two alcohols react. This is a condensation reaction because a water molecule is
eliminated from the two alcohols and appears as a reactant.
SCH4U
Date: __________________
ALDEHYDES
AND
KETONES
Aldehydes
 Organic compounds with carbonyl groups at the end of the chain.
 General formula:
Ketones
 Organic compounds with carbonyl groups bonded to two carbon atoms.
 General formula:
Naming Aldehydes and Ketones
To name an aldehyde:
1. Take the parent alkane name.
2. Drop the “e” ending.
3. Add “al”
To name a ketone:
1. Take the parent alkane name.
2. Drop the “e” ending.
3. Add “one”
4. Indicate the position of the carbonyl
group, unless there is only one possibility.
Examples:
1.
Draw the structural diagram and write the IUPAC name for an aldehyde and ketone, each
containing three carbon atoms.
2. Name the following compounds:
a.
b.
Properties of aldehydes and ketones
 Aldehydes and ketones are polar molecules because of the polar carbon-oxygen double bond.
 Their boiling points are lower than alcohols of similar sizes because the do not form hydrogen bonds.
 They are more soluble in water then hydrocarbons.
 These compounds are soluble in both polar and nonpolar substances.
Oxidation reactions of alcohols forming aldehydes and ketones
 In organic chemistry oxidation generally implies a gain of oxygen or a loss of hydrogen.
 Alcohols can be oxidized by a reactive oxygen atom. The oxygen atom removes two hydrogen atoms
from the alcohol producing water and an aldehyde or a ketone.
 When a primary alcohol is oxidized an aldehyde is produced.
 When a secondary alcohol is oxidized a ketone is produced.
 Tertiary alcohols do not undergo this type of oxidation because no hydrogen is available on the central
carbon atom.
SCH4U
Date: __________________
Hydrogenation of aldehydes and ketones producing alcohols
 The double bond in a carbonyl group of an aldehyde or ketone can undergo an addition reaction with
molecular hydrogen to produce an alcohol.
 High temperatures, pressures and catalysts are needed for these reactions.
 Addition of hydrogen to an aldehyde produces a primary alcohol.

Addition of hydrogen to a ketone produces a secondary alcohol.