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SAMPLE PROBLEM
13.1
Naming Alcohols
Give the IUPAC name for the following:
SOLUTION
STEP 1 Name the longest carbon chain containing the —OH group.
The parent chain is pentane; the alcohol is named pentanol.
STEP 2
Number the longest chain starting at the end closer to the —OH
group. The carbon chain is numbered to give the position of the —OH
group as carbon 2 to give 2-pentanol.
STEP 3
Name and number other substituents relative to the —OH group.
With a methyl group on carbon 4, the compound is named 4-methyl-2pentanol.
STUDY CHECK
Give the IUPAC name for the following:
Timberlake: General, Organic & Biological Chemistry
Copyright ©2010 by Pearson Education, Inc.
SAMPLE PROBLEM
13.2
Thiols
Draw the condensed structural formula of the following:
a. 1-butanethiol
b. cyclohexanethiol
SOLUTION
a. This compound has a —SH group on the first carbon of a butane chain:
b. This compound has a —SH group on cyclohexane:
STUDY CHECK
What is the condensed structural formula of ethanethiol?
Timberlake: General, Organic & Biological Chemistry
Copyright ©2010 by Pearson Education, Inc.
SAMPLE PROBLEM
13.3
Ethers
Give the IUPAC name for the following:
SOLUTION
STEP 1 Write the alkane name of the longer carbon chain:
STEP 2
Name the oxygen and smaller alkyl group as a substituent called
an
alkoxy group:
STEP 3
Number the longer carbon chain from the end nearer the alkoxy
group and give its location.
STUDY CHECK
What is the common name of ethoxybenzene?
Timberlake: General, Organic & Biological Chemistry
Copyright ©2010 by Pearson Education, Inc.
SAMPLE PROBLEM
13.4
Isomers
Draw the condensed structural formulas and give the IUPAC and common names of two alcohols and one ether
with a molecular formula of C3H8O.
SOLUTION
To draw the condensed structural formulas for alcohols, the hydroxyl group is bonded to two different atoms in a
chain of three carbon atoms. For the ether, two alkyl groups are bonded to an oxygen atom:
STUDY CHECK
Write the IUPAC names of the unbranched isomers of C4H10O.
Timberlake: General, Organic & Biological Chemistry
Copyright ©2010 by Pearson Education, Inc.
SAMPLE PROBLEM
13.5
Cyclic Ethers
Identify the following as a cyclic alcohol, ether, or cyclic ether:
SOLUTION
a. A cyclic ether has an oxygen atom in the ring.
b. A cyclic alcohol has a hydroxyl group bonded to a cycloalkane.
c. An ether has an oxygen atom with single bonds to two carbon groups.
STUDY CHECK
What is the difference between furan and pyran?
Timberlake: General, Organic & Biological Chemistry
Copyright ©2010 by Pearson Education, Inc.
SAMPLE PROBLEM
13.6
Physical Properties of Alcohols, Ethers, and Phenols
Predict which compound in each of the following pairs will be more soluble in water:
a. butane or 1-propanol
b. 1-propanol or 1-heptanol
SOLUTION
a. 1-Propanol is more soluble because it can form hydrogen bonds with water.
b. The 1-propanol is more soluble because it has a shorter carbon chain.
STUDY CHECK
Dimethyl ether and ethanol both have molar masses of 46 g/mole. However, ethanol has a much higher boiling
point than dimethyl ether. How would you explain this difference in boiling points?
Timberlake: General, Organic & Biological Chemistry
Copyright ©2010 by Pearson Education, Inc.
SAMPLE PROBLEM
13.7
Dehydration of Alcohols
Draw the condensed structural formula of the alcohol that is needed to produce each of the following products:
SOLUTION
a. Because the molecule is a symmetrical alcohol, the —H may be removed from the either carbon adjacent to the
carbon attached to the —OH group, which forms the following product:
b. The —OH of this alcohol is removed along with a —H from an adjacent carbon. Remember that the hydrogen
atoms are not drawn in this type of geometric formula:
STUDY CHECK
What is the name of the alkene produced by the dehydration of cyclopentanol?
Timberlake: General, Organic & Biological Chemistry
Copyright ©2010 by Pearson Education, Inc.
SAMPLE PROBLEM
13.8
Predicting Reactants
Draw the condensed structural formula for the alkenes produced by the dehydration of the following alcohols:
SOLUTION
STUDY CHECK
What is the name of an alcohol that forms 2-methylpropene?
Timberlake: General, Organic & Biological Chemistry
Copyright ©2010 by Pearson Education, Inc.
SAMPLE PROBLEM
13.9
Oxidation of Alcohols
Draw the condensed structural formula of the aldehyde or ketone formed by the oxidation of each of the
following:
SOLUTION
a. A secondary (2˚) alcohol oxidizes to a ketone:
b. A primary (1˚) alcohol oxidizes to an aldehyde:
STUDY CHECK
Draw the condensed structural formula of the product formed by the oxidation of 2-propanol.
Timberlake: General, Organic & Biological Chemistry
Copyright ©2010 by Pearson Education, Inc.