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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 attached to the —OH group by replacing the e in the corresponding alkane
name with ol. To name the alcohol, the e in alkane name pentane is replaced by ol.
Step 2
Number the chain starting at the end nearer to the —OH group. This carbon chain is numbered from right to
left to give the position of the —OH group as carbon 2, which is shown as a prefix in the name 2-pentanol.
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Sample Problem 13.1 Naming Alcohols
Continued
Step 3
Give the location and name of each substituent relative to the —OH group.
Study Check 13.1
Give the IUPAC name for the following:
Answer
3-chloro-1-butanol
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Sample Problem 13.2 Naming Phenols
Give the IUPAC and common names for the following:
Solution
Step 1
Name an aromatic alcohol as a phenol. The compound is a phenol because it contains an —OH group
attached to a benzene ring.
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Sample Problem 13.2 Naming Phenols
Continued
Step 2
Number the chain starting at the end nearer to the —OH group. For a phenol, the carbon atom attached to the
—OH group is carbon 1.
Step 3
Give the location and name for each substituent relative to the —OH group. For the common name, use the
prefix ortho (o-).
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Sample Problem 13.2 Naming Phenols
Continued
Study Check 13.2
Give the IUPAC and common names for the following:
Answer
4-methylphenol (p-methylphenol; p-cresol)
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Sample Problem 13.3 Naming Ethers
Give the IUPAC name for the following:
CH3—CH2—O—CH2—CH2—CH2—CH3
Solution
Step 1
Write the alkane name of the longer carbon chain.
Step 2
Name the oxygen and smaller alkyl group as an alkoxy group.
Step 3
Number the longer carbon chain from the end nearer the alkoxy group and give its location.
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Sample Problem 13.3 Naming Ethers
Continued
Study Check 13.3
What is the IUPAC name of methyl phenyl ether?
Answer
methoxybenzene
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Sample Problem 13.4 Classifying Alcohols
Classify each of the following alcohols as primary (1°), secondary (2°), or tertiary (3°):
a. CH3—CH2—CH2—OH
b.
Solution
a. The carbon atom bonded to the —OH group is attached to one alkyl group, which makes this a primary (1°) alcohol.
b. The carbon atom bonded to the —OH group is attached to three alkyl groups, which makes this a tertiary (3°) alcohol.
Study Check 13.4
Classify the following alcohol as primary (1°), secondary (2°), or tertiary (3°):
Answer
secondary (2°)
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Sample Problem 13.5 Dehydration of Alcohols
Draw the condensed structural formula for the major alkene produced by the dehydration of each of the following
alcohols:
a.
b.
Solution
a. The 1-butanol loses —OH from carbon 1 and H— from carbon 2 to form 1-butene. This is the only possible product.
CH3—CH2—CH CH2
b. For the dehydration of an asymmetrical alcohol, we use Saytzeff’s rule to remove —OH from carbon 2 and H— from
carbon 3, which has the smaller number of H atoms. The major product is 2-pentene.
CH3—CH—CH—CH2 CH3
Study Check 13.5
What is the name of the alkene produced by the dehydration of cyclopentanol?
Answer
cyclopentene
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Sample Problem 13.6 Oxidation of Alcohols
Draw the condensed or line-angle structural formula for the aldehyde or ketone formed by the oxidation of each of the
following:
a.
b.
Solution
a. This is a secondary (2°) alcohol, which oxidizes to a ketone.
b. This is a primary (1°) alcohol, which oxidizes to an aldehyde.
Study Check 13.6
Draw the condensed structural formula for the product formed by the oxidation of 2-pentanol.
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.
Sample Problem 13.6 Oxidation of Alcohols
Continued
Answer
General, Organic, and Biological Chemistry: Structures of Life, 5/e
Karen C. Timberlake
© 2016 Pearson Education, Inc.