1.) The compound shown below is planar and all the C-C bond lengths are the same.
What can you deduce about the bonding of boron from these observations?
CH3
B
a) The boron is sp2 hybridized and the p orbital contains an unshared pair of
electrons.
b) The boron is sp3 hybridized and a hybrid orbital contains an unshared
pair of electrons.
c) The boron is sp3 hybridized and a hybrid orbital is vacant.
d) The boron is sp2 hybridized and the p orbital is vacant.
e) None of the above.
2.) Which one of the following is best classified as a heterocyclic aromatic
compound?
NH2
NH
NH
a.)
b.)
N
c.)
d.)
N
e.)
3.) How many pairs of degenerate π molecular orbitals are found in benzene?
a) 6
b) 5
c) 4
d) 3
e) 2
4.) Which is the correct name of the compound shown below?
NO 2
Cl
NO 2
a) 1-chloro-2,5-dinitrobenzene b.) 2-chloro-1,4-dinitrobenzene
c) 1-chloro-p-dinitrobenzene
d.) p-dinitrochlorobenzene
e) More than one of these is correct.
5.) How many benzylic hydrogens are present in the molecule shown below?
a) 3
b) 4
c) 5
d) 6
e) 8
6.) Consider the following statements concerning the effect of a trifluoromethyl group,
~CF3, on an electrophilic aromatic substitution.
I. The ~CF3 group will activate the ring.
II. The ~CF3 group will deactivate the ring.
III The ~CF3 group will be a meta director.
IV. The ~CF3 group will be an ortho, para director.
Which of the statements above are correct?
a) I, III
b) I, IV
c) II, III
d) II, IV
e) None are correct.
7.) Which one of the following is the most stable?
H
Br
H
Br
H
Br
Br
H
+
HC
H
+
HC
+
C
a.)
NH2
+
NH2
b.)
c.)
NH2
NH2
d.)
8.) All the following groups are activating ortho, para directors when attached to a
benzene ring except:
a.) OCH3
b.) NHCOCH3
c.) Cl
d.) OCOCH3
e.) N(CH3)2
9.) Which of the following phenols has the largest pKa value?
OH
OH
a.)
Cl
b.)
NO 2
OH
c.)
CH3
OH
d.)
CN
10.) Which of the following is antiaromatic?
H
H
H
-
H
H
+
C
a.)
H
C
b.)
c.)
d.)
11.) Identify the aromatic compounds.
H
N
I.)
a.) I and II
II.)
N
b.) III and IV
III.)
IV.)
c.) I, II, and IV
d.) all are aromatic
12.) Which of the following is not a requirement for a molecule to be labeled as aromatic
according to Huckel’s Rule?
a.)
b.)
c.)
d.)
e.)
The molecule must be planar.
The molecule must be cyclic.
All atoms in the ring must be carbon.
The molecule must be continuously conjugated.
The molecule must have 4n+2 pi electrons.
13.) Which of the following is an intermediate of nucleophilic aromatic substitution?
a.) Wheland intermediate
d.) Meisenhiemer complex
e.) A and C f.) B and D
b.) benzyne
c.) arenium ion
g.) None of the above
14.) Which reaction is reversible?
a.) Nitration
d.) Sulfonation
b.) Friedal-Crafts Alkylation
e.) Friedal-Crafts Acylation
c.) Halogenation
15.) Why do aromatic compounds undergo electrophilic substitution rather than
electrophilic addition?
a.) Formation of the substituted benzene is highly exergonic.
b.) The addition product is much less stable than the substitution product since it is
not aromatic.
c.) Aromatic compounds are not nucleophiles.
d.) Aromatic compounds do not react with most electrophiles.
e.) None of the above.
16.) What is the order of decreasing activity for the following compounds towards
nitration? (fastest  slowest)
CH3
Cl
O
1
2
3
a.) 3 > 1 > 2 > 4
CH3
NO 2
4
b.) 2 > 3 > 1 > 4 c.) 1 > 2 > 4 > 3 d.) 3 > 4 > 1 > 2
17.) Which of the following is the electrophile in Friedal-Crafts Acylation?
O
HO
+
O
+
a.) H2C
CH3
b.)
+
CH3
c.) C
+
+
d.)
CH3
18.) The Hoffman Elimination is different from other eliminations because:
a.)
b.)
c.)
d.)
e.)
It forms the non-Zaitsev product.
It proceeds through a carbocation intermediate.
It requires antiperiplanar geometry.
It forms the Zaitsev product.
None of the above.
19.) The product of the Hoffman Elimination is an
a/an
.
a.)
b.)
c.)
d.)
e.)
alkyne/quaternary ammonium salt
alkyne/NH2
alkene/quaternary ammonium salt
alkene/NH2
alkene/ammonia
and the leaving group is
20.) Rank the following in order of increasing pKb. (smallest  largest)
H
N
NH2
H
N
H2N
CH3
2
1
3
4
a.) 2 < 3 < 1 < 4 b.) 3 < 2 < 1 < 4
c.) 3 < 2 < 4 < 1
d.) 1 < 4 < 2 < 4
21.) Which of the following has the compounds shown in correct order of decreasing
acidity? (most acidic  least acidic)
OH
OH
OH
NO 2
NO 2
1
a.) 1 > 2 > 3
3
2
b.) 3 > 2 > 1
c.) 1 > 3 >2
d.) 2 > 3 >1
22.) Which mechanism accounts for the reaction of 4-bromo-1-nitrobenzene with sodium
hydroxide to form 4-nitrophenol?
a.)
b.)
c.)
d.)
bimolecular nucleophilic substitution (SN2)
nucleophilic aromatic substitution by benzyne
nucleophilic aromatic substitution by addition elimination
electrophilic aromatic substitution
23.) What is the electrophile in the reaction of benzene with a mixture of nitric acid and
sulfuric acid?
a.) HONO
b.) NO+
c.) NO2+
d.) benzene
24.) Which of the following undergoes the fastest acylation upon treatment with acetyl
chloride in aluminum chloride?
a.) benzene
b.) toluene
c.) chlorobenzene
d.) nitrobenzene
25.) What is the value of n from Huckel’s Rule for the following aromatic compound?
a.) 3
b.) 4
c.) 5
d.) 9
26.) Identify the site of protonation when one equivalent of HCl is added to the
following compound.
H
N 2
N
1
a.) N1
b.) N2
c.) both nitrogens
d.) neither nitrogen
27.) What is the correct assignment of names for the following heterocycles?
a.)
b.)
c.)
d.)
O
H
N
S
1
2
3
1 = pyrrole, 2 = thiophene, 3 = pyridine
1 = thiophene, 2 = furan, 3 = pyrrole
1 = furan, 2 = pyrrole, 3 = thiophene
1 = furan, 2 = thiophene, 3 = pyrrole
1.) Cyclooctatetraene is not particularly stable and easily reacts with K metal to form a
very stable dianion. Using the polygon rule, draw the energy diagram for the molecular
orbitals of cycooctatetraene dianion to help explain this observation. Label each
molecular orbital as bonding, non-bonding, or anti-bonding. Circle pairs of degenerate
orbitals.
-
CH
+ 2K
-
CH
2.) Cyclopentadiene has a pKa of 16 while most hydrocarbons have a pKa > 45. Explain
why cyclopentadiene is unusually acidic.
3.) Which is more basic, pyridine or pyrrole? Explain your choice.
4.) Explain why para-cyanophenol is more acidic than phenol. Use resonance structures
as a part of your explanation.
5.) Provide structures for letters a through f.
ClCOCH 2CH 2CH 3
a
Zn(Hg)
c
HCl
c
NBS
hv
KMnO 4
H3O
e
b
H2SO 4
AlCl 3
a
HNO 3
KOH
heat
d
+
f
6.) Complete the synthesis shown below. Show all reagents, solvents, and intermediate
products. Assume isomers can be separated.
CH3
NO 2
7.) Complete the synthesis shown below. Show all necessary reagents, solvents, and
intermediate products. Assume isomers can be separated.
O
Br
CH3
CH3
NO 2
8.) Predict the products for the following reaction. Show the complete mechanism
including the resonance structures that demonstrate why the products you have chosen
are made.
Br
HNO 3
H2SO4
9.) Consider the reaction shown below:
OCH 3
ClCOCH 2CH 2CH 3
AlCl 3
a.) Determine the products of the reaction.
b.) Write a mechanism for this reaction which explains the formation of the products you
have drawn. Show all intermediates and resonance structures and indicate the flow of
electrons with arrows. Give a brief statement that explains why the products you have
drawn are formed when ~OCH3 is on the ring.
10.) Predict the products for the following reaction. Show the complete mechanism
including the resonance structures that demonstrate why the products you have chosen
are made.
CN
Br2
FeBr3
11.) Predict the products for the following reaction. Show the complete mechanism
including the resonance structures that demonstrate why the products you have chosen
are made.
CH2 CH2 CH3
(CH 3)2CHCH 2Cl
AlCl 3
12.) Predict the products for the following reaction. Show the complete mechanism
including the resonance structures that demonstrate why the products you have chosen
are made.
F3C
SO3
H2SO4
13.) Predict the product for the following reaction. Show the mechanism including the
resonance structures for the intermediate.
Br
NaOH
CN
14.) What product would you expect from the Hoffman Elimination of the following
amine? What are the reagents for this reaction?
H
N
CH3
CH3
15.) Determine the products of the following reactions.
OH
O
NaOH
+
H3C
Cl
a.)
H3C
CH3
KMnO 4
CH3
b.)
H3O
H3C
H3C
+
CH3
NBS
CH3
c.) H3C
CH3
OH
SO3
H2SO4
d.)
OCH 3
CH 3CH 2CH 2CH 2Cl
e.)
CH3
AlCl 3
hv
H2O
O
HN
CH3
CH 3CH 2Cl
AlCl 3
f.)
SH
Br2
FeBr 3
g.)
OH
HNO 3
H2SO4
CN
h.)
CF 3
ClCOCH 3
AlCl 3
i.)
O
HN
CH3
HNO 3
H2SO 4
j.) H2N
O
CH 3CH 2CH 2CH 2Br
k.)
NH3
+
N
N
CuBr
l.)
O
CH3
H3C
CH 3NH 2
a
H3O
m.)
N
1.)LiAlH 4,ether
+
2.)H 3O
+
+
N
HBF 4
n.)
O
NH(CH2CH3)2
H3C
CH3
a
H3 O
o.)
+
2.)H3O
NaCN
H3C
p.)
Br
1.)LiAlH4,ether
a
1.)LiAlH4,ether
HCN
H3O
+
+
NaN3
H3C
Br
a
1.)LiAlH4,ether
H3O
q.)
Cl
H3C
2 NH2CH3
O
r.)
H3O
a
+
1.)LiAlH4,ether
+
H3O
+
Br
NaOH
s.)
+
N
N
CuCl
t.)
O
NH 2OH
H3C
u.)
CH3
+
H3 O
N
N
KI
v.)
+
1.)LiAlH4,ether
a
2.)H3O
+
NH2
NaNO 2
a
CuCN
HCl
w.)
O 2N
H2NNH 2
KOH
O
H3C
x.)
N2
+
OCH 3
y.)
H3C
N
CH3
1.) H2O2
2.) Heat
z.)