Organic chemistry

Chapter 17—Alcohols and Phenols

SHORT ANSWER

Drawing Instructions: Draw structures corresponding to each of the given names.

1. Draw: cis-4-tert-butylcyclohexanol

ANS:

2. Draw: 3-methyl-2-buten-1-ol

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3. Draw: 2-phenyl-2-propanol

ANS:

4. Draw: glycerol

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5. Draw: 2, 4, 6-trinitrophenol

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IUPAC Naming Instructions: Provide proper IUPAC names.

6. Name:

ANS:
(E)-2-ethylbut-2-en-1-ol

7. Name:

HOCH2CH2OH

ANS:
1, 2-ethanediol or ethylene glycol

8. Name:

ANS: allyl alcohol or 2-propen-1-ol

9. Name:

ANS: hydroquinone or p-dihydroxybenzene or 1,4-benzenediol

Exhibit 17-1
Rank the following groups of compounds from most acidic (1) to least acidic (4). Place the number corresponding to the compound's relative rank in the blank below the structure.

10.

ANS:

11.

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12.

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13. Explain why nonafluoro-2-methyl-2-propoxide is a much weaker base than tert-butoxide.

ANS:
Nonafluoro-2-methyl-2-propoxide anion is more stable than tert-butoxide anion because the electron-withdrawing fluoride atoms inductively delocalize the negative charge. Since nonafluoro-2-methyl-2-propoxide is more stable than tert-butoxide, it is a weaker base.

Exhibit 17-2
Refer to the data below to answer the following question(s).

pKas of Some Phenols

Y pKa H
9.89

m-NO2
8.28

p-NO2
7.17

m-OCH3
9.65

p-OCH3
10.21

14. Refer to Exhibit 17-2. The weakest acid in the table is:

ANS: p-methoxyphenol 15. Refer to Exhibit 17-2. Which of the acids in the Table has the weakest conjugate base?

ANS: p-nitrophenol 16. Refer to Exhibit 17-2. How do you account for the difference in acidity between meta and para-nitrophenol?

ANS:
In m-nitrophenol, the inductive effect of the electron-withdrawing nitro group helps to stabilize the negative charge on oxygen.