Chapter 16 Enolate Anions
Multiple Choice
1. What is the order of increasing acidity for these compounds (least acidic first)? (Sec. 16.2)
a) IV, III, II, I
b) IV, II, III, I
c) II, III, I, IV
d) III, II, I, IV
2. What is the order of decreasing acidity for the indicated protons (most acidic first)? (Sec. 16.2)
a) I, II, III, IV
b) III, IV, II, I
c) II, I, III, IV
d) IV, III, II, I
3. Which compound undergoes the fastest exchange of hydrogen for deuterium when treated with D2O and a trace of OD-? (Sec. 16.2)
4. Which are contributing resonance structures of the enolate formed by the treatment of butanone with base?
(Sec. 16.2)
a) II, IV, V
b) I, III, V
c) II, IV, V
d) I, III, IV
5. Which are the most important contributing structures for the enolate formed by the treatment of 2,4-pentanedione with base? (Sec. 16.2)
a) I, II
b) II, III
c) III, IV
d) I, IV
6. Which are the reactants for the aldol product shown? (Sec. 16.3)
7. Which is the product of the series of reactions? (Sec. 16.3)
8. Which is the major product of the following reaction? (Sec. 16.3)
9. Which of the following compounds can be used in an aldol self reaction to make a product with 5 or more carbon atoms? (Sec. 16.3)
I) ethanal
II) propanone (acetone)
III) benzaldehyde
IV) acetophenone
a) I, II
b) III, IV
c) I, III
d) II, IV
10. Which is the major product from the reaction of 1,6-cyclodecanedione with hot aqueous NaOH? (Sec. 16.3)
11. How many possible compounds are formed when acetone and ethanal are mixed in the presence of base?
(Sec. 16.3)
a) 1
b) 2
c) 3
d) 4
12. How would you characterize this reaction forming fructose 1,6-bisphosphate? (Sec. 16.5)
a) aldol reaction
b) substitution
c) Claisen condensation
d) Dieckmann Condensation
13. How many possible compounds are formed when ethyl propanoate and ethyl methanoate are mixed with sodium ethoxide? (Sec. 16.4)
a) 1
b) 2
c) 3
d) 4
14. Which pair of esters is most likely to provide a useful Claisen synthesis (Sec. 16.4)
a) ethyl propanoate and ethyl ethanoate
b) ethyl benzoate and ethyl methanoate
c) ethyl ethanoate and ethyl oxalate
d) ethyl nicotinate and diethyl phthalate
15. Which is the major product formed in the following reaction? (Sec. 16.4)
16. What is the major product of the following reaction? (Sec. 16.4)
17. What is the major product of the following reaction? (Sec. 16.4)
18. Which compounds will undergo decarboxylation upon heating? (Sec. 16.4)
a) I, II
b) II, III
c) III, IV
d) II, IV
19. Which is the major product of the following series of reactions? (Sec. 16.6)
20. Which is the product of the following series of reactions? (Sec. 16.4)
21. Which ester is likely to undergo a Claisen condensation to give this product? (Sec. 16.4)
a) ethyl 2-methylpropanoate
b) ethyl butanoate
c) butyl ethanoate
d) 2-methylpropyl ethanoate
22. Which is the product of the reaction of ethyl 3-phenylpropanoate with 1) sodium ethoxide, 2) aqueous
sodium hydroxide, 3) aqueous hydrochloric acid, and 4) heat? (Sec. 16.4)
23. The following synthesis will proceed by which reaction? (Sec. 16.5)
a) Claisen condensation
b) Dieckmann condensation
c) Aldol addition
d) Aldol condensation reaction
24. Which is the major product of the following series of reactions? (Sec. 16.4)
25. Which is the major product of the following series of reactions? (Sec. 16.4)
Fill in the Blank
1. The major product of the following reaction is,
(Sec. 16.3)
2. The starting material that completes the following reaction is,
(Sec. 16.3)
3. The starting material that completes the following reaction is,
(Sec. 16.3)
4. The major product of the following reaction is,
(Sec. 16.4)
5. The major product of the following reaction is,
(Sec. 16.4)
6. The major product of the following reaction is,
(Sec. 16.4)
7. The starting material that completes the following reaction is,
(Sec. 16.6)
8. The major product of the following reaction is,
(Sec. 16.6)
9. The major product of the following reaction is,
(Sec. 16.4)
10. The starting material that completes the following reaction is,
(Sec. 16.4, 16.6)
True-False
1. The major enolate form of 2-pentanone is,
(Sec. 16.2)
2. The major enolate form of ethyl 3-oxobutanoate is,
(Sec. 16.2)
3. The position of the most acidic hydrogen of the following compound is indicated by the arrow.
(Sec. 16.2)
4. The position of the most acidic hydrogen of the following compound is indicated by the arrow.
(Sec. 16.2)
5. The major product of the reaction of two moles of ethyl benzoate with sodium ethoxide is,
(Sec. 16.4)
6. The major product of the reaction of 2,4-pentanedione and 3-buten-2-one with ethoxide followed by hydroxide, acid, and heat sequentially, is,
(Sec. 16.3)
7. 1-Cyclohexenecarbaldehyde can be produced from the following starting material and base.
(Sec. 16.3)
8. The Michael addition of dimethylamine and 3-buten-2-one produces the following product,
(Sec. 16.6)
9. The condensation of acetoacetyl-CoA with acetyl-CoA is an Aldol reaction. (Sec. 16.5)
10. The self condensation of Acetyl-CoA to Acetoacetyl-CoA is a Claisen reaction. (Sec. 16.5)
Answers
Multiple Choice
1. d
2. b
3. d
4. b
5. b
6. a
7. c
8. b
9. d
10. d
11. d
12. a
13. b
14. c
15. a
16. c
17. b
18. c
19. a
20. b
21. b
22. d
23. a
24. c
25. c
Fill in the Blank
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
True-False
1. F
2. F
3. T
4. F
5. F
6. F
7. F
8. T
9. T
10. T
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