Old exam questions for Week 7 material
Page 1 of 13 pages
Something to keep in mind while using these questions: Questions on the exam will be
different and many will generally not be asked in the same fashion as these. If you need to
refer to the text while working these problems then you do not know the material well
enough to do well on the exam. For many students, it is best to work the suggested text
problems first, and then do these problems after you feel that you have mastered the
information.
1. From the following, choose the intermediate electrophile that is generated in when
benzene is brominated.
A
B
Br
FeBr3
Br
FeBr3
Br Br FeBr3
Br
E
D
C
Br Br FeBr3
Br
FeBr3
2. Give the major product(s) of the following reaction.
SO 3, H2SO4
major product?
A
B
SO2
C
SO3
E
D
SO3H
SOHO
SO 4H
3. Give an intermediate that is formed that leads to an electrophilic aromatic substitution
product.
HNO3, H2SO4
intermediate?
A
H
B
NO3H
C
H
H2O NO2
E
D
NO3
NO2
H2O SO3H
4. Give the reagents that would best accomplish the following transformation.
best reagents?
A
B
Cl
+ HCl
C
+ AlCl3
Cl
+ HF
D
Cl
+ AlCl3
E
Cl
+ H3PO4
Old exam questions for Week 7 material
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5. Give the major product of the following reaction.
SO3
PCl5
major product?
A
B
SO2Cl
C
SO3H
D
SO2
E
SO3H
SO4H
Cl
Cl
Cl
Cl
6. Consider the following reaction coordinate diagram for an electrophilic aromatic substitution
reaction and choose the statement that is true.
A. The nitration reaction of benzene has a higher Ea1 than
that of nitrobenzene.
B. The nitration reaction of chlorobenzene has a higher Ea1
than that of benzene
C. The rate of reaction of the nitration of benzene is
Ea2
dependent on Ea2.
E
Ea1
D. The nitration of phenol has a higher Ea1 than that of
benzene.
E. Two of the above are correct
Reaction Coordinate
7. Rank the following compounds in order of decreasing reactivity toward electrophilic
aromatic substitution (fastest reaction → slowest reaction).
NMe3
CH3
1
2
A 4>2>1>3
B 2>4>1>3
Cl
OMe
3
C 2>3>1>4
4
D 4>1>3>2
E 4>2>3>1
8. Choose the substituents below that are ortho-para directors due to resonance.
CH3
1
A 3 and 5
Cl
2
B 1, 3, and 5
OH
3
C 2, 3 and 5
NO2
4
NH2
5
D 2 and 4
E 3 and 4
Old exam questions for Week 7 material
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9. Choose the substituents below that deactivate benzene by induction only.
CH3
Cl
1
A 2, 4 and 5
CF3
2
NO2
3
B 1, 3, and 5
NMe3
4
C 2, 3, 4 and 5
5
D 1 and 3
E 2, 3 and 5
10. Give the major product(s) of the following reaction.
CF3
HNO3, H2SO4
major product(s)?
A
B
CF3
C
CF3
D
CF3
NO2
E
Two of the
above are
major products
O2 N
NO2
NO2
11. Give the major product of the following reaction.
O
Cl C CH3
O
N C
H
A
B
O
N C
H
O
N C
H
C O
H3C
major product?
AlCl3
C
O
C
CH3
O
N C
H
O C
CH3
D
O
C
H3C
O
N C
H
E This reaction will not occur
12. From the following, choose the intermediate electrophile that is generated when benzene is
sulfonated (the electrophile that attacks benzene in the mechanism of the reaction).
-
A. HSO3
B. HSO3
C. H2SO4
D. SO3
+
E. SO3
13. From the following, choose the intermediate electrophile that is generated when benzene is
nitrated (the electrophile that attacks benzene in the mechanism of the reaction).
-
A. HNO3
B. HNO3
+
C. NO2
D. NO2
+
E. HSO4NO
Old exam questions for Week 7 material
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14. Give the reagent(s) required to accomplish the following reaction.
NO2
Reagent(s)?
A. HNO3, H3O
B. NO2H, OH-
+
-
D. HNO3, HSO4
C. HNO3, H2SO4
E. H2NO3, HSO4
15. Give the major monosubstitution product of the following reaction.
+
CH 3 CHCH=CH 2
HF
Major Monosubstitution
Product?
CH 3
A.
B.
CH3
CH2 CH2 CHCH 3
D.
C.
CH3
CH 3CHCH2 CHCH 3
F CH 3
CH3 CHCCH3
E.
F CH 3
CH 3CHCHCHCH3
CH3
CH3 CH2 CCH3
Old exam questions for Week 7 material
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16. Give the reactants that complete the following reaction.
O
+
A.
Reactants?
B.
O
C
OH
O
C
O
C.
H
Ph
+
and H
O
and OH
E.
O
C
NH2
O
Cl
C
+
and AlCl3
and H
17. Give the major product of the following reaction.
OH
BF3
Major Product?
+
OH
B.
A.
OH
C.
D.
Ph
-
and AlCl3
D.
O
E.
Old exam questions for Week 7 material
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18. Rank the following in order of decreasing electrophilic aromatic substitution reactivity.
(fastest reaction → slowest reaction).
OH
O
CH3
1
2
3
CH3
C
4
A. 1>2>3>4
B. 3>2>1>4
C. 4>2>3>1
D. 1>3>2>4
E. 1>4>3>2
19. Give the major product(s) of the following reaction.
O
C
CH3
Br2, FeBr3
Major Product(s)?
A.
O
C
B.
CH3
O
C
C.
CH 3
O
C
CH3
Br
Br
Br
D.
E.
O
C
Both A and C
are products
CH2Br
20. Give the major product(s) of the following reaction.
SO3H
+
H , H2O
Major Product(s)?
A.
B.
SO3H
C.
SO3H
SO3H
OH
OH
OH
E.
D.
Both A and C
are products
Old exam questions for Week 7 material
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21. Choose the most important resonance form of the intermediate that is formed, in the
mechanism of the reaction, when an electrophile (E+) attacks dimethylaniline at the ortho
position.
N(CH3)2
A.
(CH3)2N
+
E
Most Important
Intermediate Resonance
Form?
B. (CH ) N
32
E
C.
E
(CH 3)2N
E
H
H
H
E.
D.
(CH3)2N
(CH 3)2N
E
H
E
H
22. Choose the statement that is true concerning bromobenzene and electrophilic aromatic
substitution.
A. Electron donation by resonance from bromine to the benzene ring is responsible for
the deactivation of the benzene ring.
B. Brormine deactivates benzene by electron donation from the bromine to the benzene
ring. Electron donation is also responsible for directing the incoming electrophile.
C. Bromine deactivates benzene by withdrawing electrons using induction and
resonance.
D. Electron withdrawal by the bromine group is by both induction and resonance.
E. Bromine withdraws electrons by induction. Electron donation from bromine to the
benzene ring directs the incoming electrophile.
Old exam questions for Week 7 material
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23. Choose the intermediate that is generated in the mechanism of the reaction of FeBr3, Br2
with benzene.
A.
C.
B.
Br
Br
Br
Br
D.
H
FeBr3
Br
FeBr3
E.
H
Br
Br
H
H
FeBr3
24. From the following, choose the intermediate electrophile that is generated when benzene is
treated with CH3COCl and AlCl3.
A.
B.
CH3C O
C.
CH3C O
CH3C O
H
Cl AlCl3
D.
E.
CH2C O
CH2C O
H
Cl
25. Give the reagent(s) that will best accomplish the following reaction.
SO3H
Reagent(s)?
A.
B.
H2SO4
C.
SO3
D.
HSO4
-
E.
SO3, H2SO4
H2SO4, HNO3
Old exam questions for Week 7 material
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26. Give the major product of the following reaction.
Cl
CH2CHCH(CH 3)2
A.
AlCl3
Major Product?
B.
CH(CH 3)2
CH(CH 3)2
CH(CH3)2
C.
E.
D.
CH CHCH(CH 3)2
H3C
H3C
CH 3
CH3
27. Rank the following compounds in order of increasing reactivity with respect to electrophilic
aromatic subsitution (most reactive → least reactive).
Br
OCH3
CH3
2
1
A. 1>2>3>4
SO3H
3
B. 2>4>3>1
4
C. 3>1>2>4
D. 1>3>2>4
E. 1>3>4>2
28. Give the major product(s) of the following reaction.
O
CH3Cl
Major Product(s)?
O C
AlCl 3
A.
H 3C
B.
H3C
O
O
O C
O C
C.
CH 3 E.
D.
O
O
O C
O C
H3C
Two of the above are
major products
Old exam questions for Week 7 material
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29. Choose from the below the mechanism of attack of an electrophile (E) on benzene (a
mechanistic step in electrophilic aromatic substitution).
A
B
E
E
C
E
H
E
E
H
E
H
E
D
E
E
E
H
E
H
30. Give the major product of the following reaction.
HNO3, H2SO4
O
A
B
HSO3
NO2
Major Product(s)?
CH3
E
D
C
NO2
Both B and
C are major
products
NO2
O
CH3
O
CH3
O
CH3
O
CH3
31. Rank the following compounds in order of decreasing reactivity toward electrophilic
aromatic substitution (fastest reaction → slowest reaction).
O
A. 2>1>4>3
NO 2
CH3
Cl
1
2
3
B. 4>3>2>1
C. 1>3>4>2
OCCH3
4
D. 4>2>3>1
E. 2>3>4>1
Old exam questions for Week 7 material
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32. Give the major product of the following reaction.
HNO3
major product?
H2SO4
A
B
C
SO
D
E
NO2
SO3H
NO3
SO3H
NO2
33. Give an intermediate that is formed in the following reaction.
O
Cl
intermediate?
AlCl 3
B
A
H
C
O C
D
H
O
O
C
E
O
C
O
34. Give the major product of the following reaction.
H3PO 4
major product?
+
B
A
C
D
E
35. From the substituents shown below, choose the one(s) that deactivates benzene.
A
-CH3
B
-NH2
C
-OCH3
D
O
E
CH3
Two of the above
deactivate benzene
Old exam questions for Week 7 material
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36. Rank the following compounds in order of decreasing reactivity toward electrophilic
aromatic substitution (greatest reactivity → least reactivity).
O
SO3H
CH3
HN
2
1
NH2
Br
3
4
A. 3>2>4>1
B. 4>3>1>2
D 2>3>4>1
E. 1>4>3>2
C. 2>3>1>4
37. Which statement best characterizes the properties of -NO2 as a substitutent to benzene?.
A.
B.
C.
D.
E.
Inductive electron donating, resonance electron withdrawing.
Inductive electron donating, no resonance effect
No inductive effect, resonance electron withdrawing.
Inductive and resonance electron donating.
Inductive and resonance electron withdrawing.
38. Give the most important intermediate resonance form that represents the directing effect
of the the methoxy group in the monochlorination of the following compound.
OCH3
A
O
CH3
B
O
most significant
intermediate
resonance form?
C
CH3
O
CH3
D
O
E
CH3
O
CH3
Cl
H
Cl
H
Cl
H
H
Cl
H
Cl
39. Choose the reagents that will best accomplish the following reaction.
reagents?
A H2SO4, H2O
B
conc. H2SO4
C
SO3, H2SO4
SO3H
D SO4, H3PO4
E
HNO3, H2SO4
Old exam questions for Week 7 material
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40. Give the product from the monochlorination of the following compound.
O
C
A
B
Cl
O
C
monochlorination
major product?
Cl
C
Cl
O
C
Cl
D Cl
O
C
Cl
E
O
C
Cl
Cl
O
C
Cl
Cl
Cl
41. Give the major product(s) from the following reaction sequence.
HNO3
Br2
H2SO4
FeBr3
major product(s)?
Br
A
C
B
D
E
SO3H
Br
two of the above
are major products
Br
NO2
NO2
Br
NO2
42. Which statement best characterizes the properties of -N(CH3)2 as a substituent to
benzene.
A. Inductive and resonance electron donating
B. Inductive electron donating, no resonance effect
C. Resonance electron donating, inductive electron withdrawing
D. Inductive and resonance electron withdrawing
E. No inductive effect, resonance electron withdrawing
43. From the choices below, give the major intermediate(s) which is formed in the following
reaction.
Br2, FeBr3
Intermediate(s)?
Product(s)
NO2
B
A
NO2
NO2
H
Br
E
D
C
NO2
H
H
Br
H
Br
Br
NO2
Two of the above
are intermediates
leading to major
products