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CHM 234, Spring 2015
QUIZ #13
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QUESTION 1
MC34a
Which of these reactions would be the best to form the
structure below
O
O
OCH3
O
A
OCH3
H3C
2. H3O+
O
O
1. Na+ –OCH3/CH3OH
O
B
+
H3CO
OCH3
excess
O
O
+
C
H3C
CH3
1. Na+ –OCH3/CH3OH
2. H3O+
Na+ –OCH3/CH3OH
heat
O
D
OCH3
H3CO
O
1. Na+ –OCH3/CH3OH
2. H3O+
QUESTION 2
MC34b
Which are the PREFERRED reagents and conditions to give the
provided structure, i.e., with the fewest competing reactions?
O
Ph
1. LDA O
2.
O
A
Ph
3. TsOH/heat
O
O
B
Ph
TsOH/heat
O
O
C
OCH3
TsOH/heat
Ph
O
D
Excess
1. LDA O
2.
Ph
3. TsOH/heat
QUESTION 3
MC34c
Which are the PREFERRED Reagents/Conditions to give the
provided structure with the fewest competing reactions?
O
O
MeO
OMe
O
A
B
1. MeO– +Na/MeOH
OMe
Excess
MeO
O
2. H3O+
O
OMe
+
1. MeO– +Na/MeOH
OMe
O
C
MeO
O
D
MeO
1. MeO– +Na/MeOH
OMe
O
OMe
+
2. H3O+
2. H3O+
1. MeO– +Na/MeOH
Excess
OMe
2. H3O+
QUESTION 4
MC34d
Identify which of the provided structures is NOT a possible
Aldol addition product in the following reaction
t-BuO– +K/DMF/heat
O
O
O
O
OH
OH
B
C
O
O
OH
A
D
O
QUESTION 5
MC34e
Which reaction coordinate best describes the self-Aldol
ADDITION (dimerization), NOT CONDENSATION, reaction for
acetone under the base catalyzed conditions shown (hint, draw
the mechanism and count the steps, consider the exothermicity)
O
O
Na+ –OMe
OH
DMF
A
B
C
D
QUESTION 6
MC34i
Addition of sodium ethoxide to ethyl acetate initiates a
Claisen reaction that generates an intermediate enolate ion.
Benzaldehyde is added to this intermediate enolate and the
product of this reaction is then treated with a small
(catalytic) amount of the organic acid TsOH and heat to
initiate dehydration. What is the final product of this
overall reaction sequence? (hint, it isn't as hard as it
sounds, just work through each step)
O
H
O
NaOEt/EtOH
OEt
ethyl acetate
O
TsOH/heat
intermediate
ion
O
O
O
O
????
O
OEt
O
EtO
HO
OEt
HO
B
A
D
C
QUESTION 7
MC34j
Using the provided bond dissociation energies, which is
the enthalpy of the following reaction? (hint, calculate
the energy cost of breaking the relevant bonds and
calculate the energy gain from making the relevant
bonds. I am not going to tell you if a positive
enthalphy of reaction is endothermic or exothermic, you
are supposed to know that by now!)
O
Ph
O
O
Ph
OCH3
OCH3
+
CH3OH
Ph
Bond
C–C
C–O
RO–H
C–H
BDE (kcal/mol)
85
91
102
99
A
9 kcal/mol
C
-9 kcal/mol
B
3 kcal/mol
D
-3 kcal/mol
QUESTION 8
MC34l
Which best describes the following equilibrium?
O
OH
TsOH (cat.)
THF
A equilibrium lies of the left because the C=O bond is
stronger than the C=C bond
B equilibrium lies on the right because the C=O bond is
stronger than the C=C bond
C equilibrium lies of the left because the C=C bond is
stronger than the C=O bond
D equilibrium lies on the right because the C=C bond is
stronger than the C=O bond
QUESTION 9
There are NO INCORRECT answers to this question, ALL
answers to this question will be considered correct for grading
purposes
What overall final grade do you expect to earn in this class?
A
B
C
D
QUESTION 10
There are NO INCORRECT answers to this question, ALL
answers to this question will be considered correct for grading
purposes
How hard did you work on organic chemistry this week (not
including watching/attending lectures)
A
B
C
D
Very Hard
Hard
Somewhat Hard
Not very Hard this week