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CHEMISTRY 212
EXAM 2
Friday, February 13, 2004
Name
Hold?
Answer all 19 questions (150 pts).
1. (12) State whether each of the following is aromatic or non-aromatic. In addition, give only the
following data which enabled you to arrive at your conclusion: fully conjugated - yes or no; # pielectrons.
a)
b)
N
c)
N
O
N
2. (7) In each example shown, circle the benzene ring most likely to react with an electrophile. You need not
explain your answer.
O
a)
b)
O2N
O
CH3
HN
3. (12) State whether each of the following molecules is activated or deactivated compared to benzene.
It is not necessary to explain why.
O
NH
a)
b)
C
c)
CH 3
O
d)
OH
4. (12) State whether further electrophilic substitution of each of the following molecules would occur in
the ortho / para or meta positions. It is not necessary to explain why.
O
O
H
a)
b)
c)
d)
S
N
Br
N
NH2
CH3
5. (8) Show the first step (complete) of the arrow-pushing mechanism for the reaction between each of
the following:
O
a)
OH
+
S
Cl
Cl
b)
+
6. (14) Synthesize the following starting from benzene or toluene. Show all steps and reagents.
Br
NO2
a)
Cl
CH3
b)
COOH
or
H3C
C
O
7. (3) One diagnostic feature in the NMR spectrum for alcohols is that on addition of D2O the signal
for the OH:
a) increases in strength
downfield
b) becomes a doublet
c) moves upfield
d) disappears
8. (6) Classify the following reagents as oxidizing or reducing.
a)
KMnO4
b)
PCC
c) NaBH4
e) moves
9. (5) Draw a Grignard reagent and carbonyl compound that could be used to form the molecule shown:
OH
10. (10) For the compound shown below, show all the resonance forms that illustrate the effect of the
group attached to the ring. In this case, you should show arrow-pushing to support your answer.
O
OH
11. (4) Draw the carbonyl compound that could be reduced by NaBH4 to form the molecule shown:
OH
12. (32) Show reasonable products, or missing reactants, for the following reactions.
a)
H
OH
O
b)
?
O
1) LiAlH
OH
c)
2) H
4
+
OH
CrO3, H2SO4
?
O
d)
H
?
OH
e)
O
H2SO4
OH
O
f)
Ph
Ph
H2
NBS
Pd
heat
13. (3) True or False? The molecule shown would react with NBS.
14. (3) True or False? In the Friedel-Crafts' alkylation shown, rearrangements would not be a problem.
+
15.
AlCl3
Cl
(3) Which one of the following compounds reacts most slowly with HNO3/H2SO4?
SO3 H
NH2
Cl
16. (4) Which of the following is the best method of preparing meta-nitrobenzoic acid from benzene?
a) CH3Cl with AlCl3; then KMnO4; then HNO3 / H2SO4
b) CH3Cl with AlCl3; then HNO3 / H2SO4; then KMnO4
c) HNO3 / H2SO4; then KMnO4; then CH3Cl with AlCl3
d) HNO3 / H2SO4; then CH3Cl with AlCl3; then KMnO4
17. (4) Which of the following sequences gives the compound shown at the left in the highest yield?
CO 2H
N O2
Br
a)
CO 2H
b)
CO 2H
HN O3/H 2SO 4
Br2/FeBr3
Br 2/FeBr 3
c)
C H3
HN O3/H 2SO 4
d)
C H3
Br 2 /FeBr 3
H NO 3/H2SO 4
HNO 3/H2SO 4
Br 2 /FeBr 3
KMnO 4, 
KMnO 4, 
18.
(4) Which one of the following alcohols is oxidized to a ketone by Jones reagent?
CH3
OH
CH2OH
OH
OH
19. (4) Which of the following reactions do not occur? More than one answer may be possible.
a. Benzene + Br2 in the presence of FeBr3; b. Nitrobenzene + 1-chlorobutane in the presence of AlCl3
c. PhCO2H + CH3COCl in the presence of AlCl3; d. Toluene + HNO3/H2SO4