Test Problems For Chapter 18 With Answers
Test Problems For Chapter 18 With Answers
Test Problems For Chapter 18 With Answers
O H3C C O
+
H H3C CH2
cat. NaOH
H
H2O
A)
OH H3C H2C C CH2 H C H O
B)
H H3C C CH C H O
CH3 OH
C)
OH H3C C CH2 H C H O
D)
OH H3C C H CH CH3 OH H3C H2C C H CH CH3 C H C H O
E)
O
Ans: B
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2. What organic molecule would you expect to be present in significant amounts under the following conditions?
O H CH3
B)
O D CH3
C)
O
D)
O CH3 D
racemic
E)
O CD3 D
racemic Ans: D
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CHO
+ CH3CHO B)
CHO O H C CHO
+ C)
O CH3
+ CH2=O
D)
O
CHO
E)
CHO O H3C C CHO
+ Ans: A
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1. (CH3)2CuLi
O
2. H2O
A)
B)
OH
C)
OH CH3
D)
E)
Ans: A
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H or HO
A) B) C) D) E) Ans:
To the right To the left Equally to right and left Cannot be predicted Major product is an enol or enolate ion, respectively A
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HC CH2
CH3
A)
B)
O
C)
O
D)
O
E)
O
Ans: A
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7. What major product would you expect from the following reaction?
O CH2=O Na+ -OCH3 CH3OH, heat ?
A)
HO OCH3
B)
CH2
C)
O CH3
D)
O CH2
E)
O
H H
CH2 CH2 C
5 3 4
2 A) 1 B) 2 C) 3 D) 4 E) 5 Ans: D
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CH3CH2CHO A)
O
KOH H2O
CHO
B)
OH CHO
C)
O OH
D)
HO CHO
E)
OH CHO
Ans: B 10. To which side, if any, would the following equilibrium lie?
OH H3C C CH2 H3C O C CH3
A) B)
D) E)
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H3C
CH2
H2O
H3C
CH3
NaOH
A) B)
D) E)
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12. Which major product would you expect when the following diketone undergoes aldol cyclization in base, followed by acid?
O O NaOCH2CH3 H3 O +
A)
O H3C
B)
O O
C)
O CH3
CH3
D)
O CH3
E)
O CH3
Ans: A
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13. Which set of reagents would be needed for the following conversion?
CH3 O CH3 O CH2Ph
A) B) C) Ans:
D) E)
14. What product results when the following aldol product is treated with dilute acid?
PhCH2 HO Ph O H
H3O+
A)
PhCH2 O H Ph
B)
Ph O CH2 O
+
H
CH2 Ph
C)
Ph O H Ph
D)
PhCH2 H Ph O OH H
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15. Which of the following sets of reaction conditions will result in the following transformation?
O OH
A)
Ans: D
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A)
OH O
B)
O
C)
O
D)
OH O
E)
Ans: B
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NaOEt / EtOH
A)
B)
C)
OH
D)
E)
O
Ans: A
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18. Predict the major organic product of the following reaction sequence.
O 1) LDA / THF O 2) EtO OEt 3) LDA / THF 4) CH3CH2OTs 5) Saponification 6) H2O / H+ 7) Heat
CH3O
A)
O
CH3O
B)
O
CH3O
C)
O O O CH3O
D)
O OEt CH3O O
E)
CH3O
Ans: A
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19. Predict the major organic product of the following reaction sequence.
O 1) LDA (0.95 eq) / THF 2) CH3OTs 3) MCPBA ?
A)
O
B)
O O
C)
D)
O
E)
O H 3C O
Ans: B
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20. The addition of either the methyl Grignard reagent or methyllithium to camphor, followed by hydrolysis, produces a tertiary alcohol known as 2-methylisoborneol, an algal metabolite which imparts a musty odor to water at very low concentrations. However, the yield of alcohol does not exceed 50%, and large amounts of camphor are recovered from the reaction even when a large excess of the Grignard or lithium reagent are used. What would be the most plausible explanation? 1. CH3MgBr or CH3Li O camphor A) B) C) 2. H2O
OH CH3 ~ 50%
Ketones do not react with Grignard or lithium reagents. The Grignard or lithium reagent had obviously degraded during storage. The mechanism requires that, for each alcohol formed, one ketone molecule must remain unreacted. D) With hindered ketones, the organometallic reagent could function as a base rather than as a nucleophile. E) Alcohol formed early in the reaction could form an unreactive hemiacetal with remaining ketone. Ans: D
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Cl2 , H
A)
Cl O
B)
HO CH3
C)
Cl OH
D)
O
Cl
E)
Ans: D
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KOH/
H
A)
O O H
B)
OH H
C)
CHO
D)
O H
E) None of these are correct. Ans: C 23. Which of the following conditions will not successfully alkylate a ketone? A) 1. H2O, H+ 2. CH3CH2OH B) 1. 2. CH3CH2Br 3. H+, H2O C) 1. LDA, THF 2. BrCH2CO2C2H5 D) 1. LDA, THF 2. (CH3)2C=CHCH2Br E) All of these will alkylate a ketone. Ans: A
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A)
HO
B)
OH
C)
O
D)
OH
E)
O
Ans: A
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A)
(CH2) 3CH3 CH2 CH3
B)
O (CH2) 3CH3 (CH2) 3CH3
C)
O (CH2) 3CH3 CH2 CH3
D)
O CH2 CH3 (CH2) 3CH3
E)
HO (CH2) 3CH3 CH2 CH3
Ans: D
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A)
B)
C)
D)
Page 22
O CH3NH2, H2O
A)
OH NHCH3
NHCH3
B)
OH
C)
NHCH3
D)
O NHCH3
NHCH3
E)
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H NCH3
Ans: C 29. Given a large excess of D2O, what product(s) would result from the following reaction at equilibrium?
D2O
O
D or -OD
A)
OD D
B)
D D D O
C)
D D D CD3 D D D O
D D3 C
D D D D O
CD3
D)
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30. The best reactants to convert cyclohexanone to 2-methylcyclohexanone cleanly would be: O
O CH3
A)
1.
N H
, H+, - H2O
2. CH3I 3. H3O+
B)
NaOH, CH3I
C)
1. LDA 2. CH3I
D)
1. CH3Li 2. H3O+
E)
Ans: A
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cat. NaOH
O A) O
H2O heat
B)
O
C) O
D)
O
OH
E)
O
OH Ans: A
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CH3OH
R
OCH3 CH OCH3
reaction I A) B) C) D) E) Ans:
reaction II
Reactions I and II are only acid-catalyzed. Reaction I is catalyzed by either acid or base, but reaction II requires acid. Reactions I and II are both base-catalyzed. Reaction II is catalyzed by either acid or base, but reaction I requires acid. Both reactions I and II are catalyzed by either acid or base. B
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