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‫بسم هللا الرحمن الرحيم‬
Organic Chemistry II
KEY
Final Exam Review Questions
By Dr. Mohammad A. R. Ismaiel
College of Science for Women
Babylon University
Thanks for the Dean of the College
Examples of the types of questions you can expect to see on the final
1.
The IUPAC name for the formula CH3CH2CH2CHOHCH=CH2 is
1.
2.
5.
2.
5-hexene-3-ol
1-hexene-5-ol
allyl n-butyl ether
2.
4.
1-hexene-3-ol
n-propyl ally alcohol
What is the order of reactivity toward SN2 displacement in the following series?
A.
B.
C.
CH3
Cl
CH3 CH2 CH2 CH2 Cl
CH3 CH2 C CH3
CH3 CH2 CH CH3
Cl
1.
3.
5.
3.
A>B>C
B>A>C
C>A>B
2.
4.
A>C>B
B>C>A
The principal organic product formed in the reaction below is
CH2 =CH(CH2 )8 COOH + HBr
peroxide
1.
CH3CHBr(CH2)8COOH
2.
CH2BrCH2(CH2)8COOH
3.
CH2=CH(CH2)8COBr
4.
CH2=CH(CH2)7CHBrCOOH
5.
none of these
CH3
4.
Treatment of
with HCl gives
CH3 C CH2 OH
CH3
1. CH3 CH2 CH2 CH2 CH2 Cl
2.
CH3 CH2 CH CH2 Cl
CH3
3.
CH3 CH2 C CH3
Cl
5.
CH3
CH3 CH CH2 CH2 Cl
CH3
CH3
4.
CH3 CH CH3
5.
A compound which is insoluble in cold, concentrated sulfuric acid is
1.
3.
5.
6.
the product will be optically active, but have the opposite configuration
the reaction will involve racemation
a carbanion is formed as an intermediate
the rate of the reaction is a function of the concentration of the nucleophile
the attacking group will be a strong electrophile
(CH3)3CCl + AgNO3 
(CH3)3COH + HCl 
(CH3)3CH + Cl2 + uv light 
CH3CH=CHCH2OH + H3O+ 
The reagent which would distinguish between 1-hexyne and 1-hexene is
1.
3.
5.
10.
sodium tert-butoxide in chloroform
hydrogen peroxide and aqueous acetic acetic acid
ozone and moist zinc dust
periodic acid
cold dilute potassium permanganate
Which does NOT involve a carbocation?
1.
2.
3.
4.
9.
1-hexene
ethyl acetate
Which statement is correct for an SN1 reaction at a chiral carbon atom?
1.
2.
3.
4.
5.
8.
2.
4.
Which reagent would convert cyclohexene into a cis-glycol?
1.
2.
3.
4.
5.
7.
n-hexane
2-hexyne
benzyl alcohol
Ag(NH3)2+
Br2 in CCl4
NaOH
2.
4.
KMnO4
H2SO4
In methyl alcohol solution, bromine reacts with ethylene (ethene) to yield BrCH2CH2OCH3
in addition to 1,2-dibromoethane because
1.
2.
3.
4.
5.
the methyl alcohol solvates the bromine.
the ion formed initially may react with Br1- or CH3OH.
this is a free radical reaction.
the reaction follows Markovnikov’s rule.
of none of these reasons.
11.
The important minor product from the reaction of sodium cyanide with 2-iodopentane in
anhydrous acetone is
1.
3.
5.
12.
2-pentene
2-pentanol
ClCH2CH2CH2CH=CH2
CH3CH2CHClCH=CH2
CH3CH2CH2CH=CHCl
2.
4.
CH3CHClCH2CH=CH2
CH3CH2CH2CCl=CH2
When a solid organic compound is recrystallized, the cold filtrate from the cooled mixture
is
1.
3.
5.
14.
2.
4.
The monochloroisomer that predominates in the mixture resulting from the free radical
chlorination of CH3CH2CH2CH=CH2 is
1.
3.
5.
13.
1-pentene
pentane
4,5-dimethyloctane
saturated with the compound.
2.
entirely free of the compound. 4.
supersaturated with the compound.
an unsaturated solution of the compound.
pure solvent.
Sodium iodide in anhydrous acetone reacts most rapidly with
1.
CH3CH2CH2Br
2.
(CH3)3CBr
3.
Br
CH3 CH CH3
4.
CH2=CHBr
5.
CH3
Br
15.
CH3CH=CHCH2OH reacts with HBr to give which two bromobutenes?
1.
CH3CH=CHCH2Br
+
CH3CH=CBrCH3
2.
CH3CH=CHCH2Br
+ CH3CHBrCH=CH2
3.
CH2=CHCH2CH2Br
+
4.
CH2=CBrCH2CH3
5.
BrCH2CH=CHCH3
CH2=CHBrCH=CH2
+ CH2=CHCH2CH2Br
+ BrCH2CH2CH=CH2
16.
What is the possible number of stereoisomers having the structure below?
OH
OH
CH3 CH CH2 CH CH3
1.
2.
3.
4.
5.
17.
The addition of Br2 to trans-2-butene giving meso-2,3-dibromobutane can be explained by
a mechanism involving
1.
3.
5.
18.
19.
two optically active and one meso
None optically active
four optically active
two optically active and two meso
one optically active and one meso
a free radical.
2.
a carbocation.
a cyclic bromonium ion.
4.
a carbanion.
simultaneous attack by to bromine atoms.
Which metal catalyzed reaction would release the greatest amount of heat per CH2 unit?
1.
cyclopropane + H2 
2.
cyclobutane + H2
3.
cyclopentane + H2
 pentane
4.
cyclohexane + H2
 hexane
5.
cyclododecane + H2
propane
 butane
 dodecane
What is the IUPAC name for the compound shown below?
CH3
CH3
CH3 CH CH C CH3
1.
2.
3.
4.
5.
20.
2,3-dimethyl-4-pentene
1,1-dimethyl-2-isopropylethene
2,3-dimethyl-2-pentene
All of the above
None of the above
Which dimethylcyclobutane has two optically forms?
1.
3.
5.
trans-1,2trans-1,31,1-
2.
4.
cis-1,2cis-1,3-
21.
The C-C-N angle in acetonitrile, CH3CN is
1.
4.
22.
60°
180°
3. 109.28°
It produces a mole of product for a mole of free radical initiated.
It gives the product derived from the most stable free radical.
It may be initiated by peroxides.
It may be initiated by high heat.
It may be initiated by ultraviolet light.
A reaction at a chiral carbon of an optically pure isomer which takes place exclusively by
an SN2 reaction, and in which priorities do not change, proceeds with
1.
2.
3.
4.
5.
24.
2.
5.
Which is NOT characteristic of a free radical chain reaction?
1.
2.
3.
4.
5.
23.
45°
120°
inversion and no racemization.
inversion and some racemization.
inversion and complete racemization.
retention of configuration and some racemization.
retention of configuration and no racemization.
Which would yield 2-methyl-2-pentene when refluxed with zinc dust in alcohol?
Br
1.
CH3
Br
2.
CH3 CH2 CH C CH3
CH3
CH3 CH2 CH CH CH3
Br
3.
CH3
4.
CH3 CH2 CH2 C CH2 Br
Br CH3
CH3 CH2 C CH CH3
Br
Br
5.
Br
Br
CH3
CH3 CH CH CH CH3
25.
Which anion is the weakest base?
1.
3.
C2H5O1CH3COO1-
2.
5.
NO31OH1-
3.
CN1-
26.
27.
Which compound would be the major product when (CH3)2CHCHBrCH2CH3 is treated
with alcoholic KOH?
1.
(CH3)2CHCH2CHOHCH3
2.
(CH3)2CHCHOHCH2CH3
3.
(CH3)2COCH2CH2CH3
4.
(CH3)2CHCH=CH3
5.
(CH3)2C=CHCH2CH3
If tert-butyl bromide and sodium amide (NaNH2) react, the product formed is
1.
2.
3.
4.
5.
28.
tert-butylamine.
(amines are R-NH2)
tert-butylammonium bromide.
a mixture of butylamines.
isobutylene. (2-methylpropene)
none of these.
In the reaction below, the product would be
CH3 CH CH CH3
1.
2.
3.
4.
5.
29.
CH3 CH2 CH CH3
a mixture of diastereomers.
opticaly active.
unresolvable.
a racemate.
a meso compound.
the same.
slower.
faster.
unpredictable.
unimolecular.
Which of the amines listed below would have the lowest boiling point?
1.
3.
5.
31.
OH
The rate of an SN2 reaction run in a polar aprotic solvent relative to the same reaction in a
polar protic solvent would be
1.
2.
3.
4.
5.
30.
+ H2 O
H3 O+
CH3CH2CH2NH2
(CH3)3N
(CH3)2CHNH2
2.
4.
CH3CH2NHCH3
(CH3)3CNH2
Racemic 2,3-dibromobutane can be made by adding bromine to
1.
3.
cis-2-butene.
1,3-butadiene.
2.
4.
1-butene.
trans-2-butene.
32.
Which species represents the electrophile in aromatic substitution?
1. :NO2-
33.
5. SO3H+
Phe-Br
4-Br-Phe-F
4-Br-Phe-COCH3
2.
4.
4-Br-Phe-Br
4-Br-Phe-CN
A good starting material for the preparation of 4-chlorobenzenesulfonic acid would be
1.
3.
5.
35.
4. NO3-
3. NO2
Which could NOT be prepared directly from 4-bromobenzene-diazonium ion?
1.
3.
5.
34.
2. NO2+
benzenesulfonic acid
chlorobenzene
1,4-dichlorobenzene
2.
4.
1,4-dinitrobenzene
4-chlorobenzioc acid
Which represents an intermediate formed in the reaction of toluene and chlorine at elevated
temperature in sunlight?
1.
2.
H
H
CH3
CH3
Cl
Cl
3.
4.
CH2
CH2
5.
H
CH3
Cl
36.
The reaction of benzyl chloride with sodium isopropoxide yields
1.
3.
5.
37.
benzaldehyde and 2-chloropropane
2. 1,2-diphenylethane and acetone
acetone and toluene
4. benzyl isopropyl ether
isopropyl ether and the sodium salt of benzyl alcohol
An aromatic hydrocarbon yields a single mononitro derivative. The hydrocarbon is
1.
3.
5.
ethylbenzene
propylbenzene
p-xylene
2.
4.
o-xylene
naphthalene
38.
Which is the best way to prepare meta-bromoaniline?
1. Phe-NH H2SO4
2
2. Phe-H
3.
4.
5.
39.
Br2
Br2
(CH3CO)2O
Phe-NO2
Phe-NO2
Phe-NO2
HNO3
H3O+
HNO3
Sn
HCl
Br2
H3O+
(NH4)2S
NaNO2
H2SO4
CuBr
Sn / HCl
HBr
H2SO4
NaOH
NaBr
Sn
fuse
HCl
Which is the principal product when benzaldehyde is allowed to react with propionaldehyde in
the presence of dilute aqueous sodium hydroxide at room temperature?
OH O
1.
CH C
O
CH2CH3
2.
CH C
CHO
CH3
3.
40.
O
O
C
C
CH2CH3
4.
CH CH CH2 CHO
Which does NOT represent a Diels-Alder type of reaction?
O
O
1.
2.
+
+
O
O
O
O
O
3.
5.
41.
CH2=CHCH=CH2 + CH2=CHCOOH
+ H2C
4. CH3COCH3 + CH3CH=CHCHO
CH CHO
Which statement about the aldol condensation is correct?
1.
2.
3.
4.
A Lewis acid is commonly used as a catalyst.
The initial step is probably the formation of a carbanion.
A Lewis base is employed to induce carbocation formation.
The carbon chain is lengthened through the elimination of 1 mole of water.
42.
Which is the strongest acid in water?
1.
3.
5.
43.
3-nitrophenol
4-nitrophenol
C6H5CH2CH2CH2Cl
C6H5CH2Cl
ClCH2COOH
2.
4.
C6H5CH2CH2Cl
C6H5Cl
A compound gives a positive test with I2/NaOH and is extracted from benzene by saturated
NaHSO3. It may be
1.
3.
5.
45.
2.
4.
The most direct malonic ester synthesis of 3-phenylpropanoic acid would involve the use of
1.
3.
5.
44.
Phenol
4-aminophenol
hydroquinone
CH3(CH2)4CHO
CH3CH2COCH2CH3
CH3(CH2)3)CHOHCH3
2.
4.
CH3(CH2)3COCH3
CH3(CH2)4CH2OH
Which is an L-sugar that on oxidation gives an optically inactive dibasic acid
(2 COOH groups)?
CHO
1.
H
CHO
2.
OH
H
HO
H
HO
HO
H
H
CH2OH
CHO
3.
OH
HO
H
OH
H
H
OH
HO
CHO
HO
H
H
OH
H
OH
CH2OH
OH
CHO
H
5.
H
CH2OH
4.
CH2OH
OH
H
OH
H
CH2OH
46.
Select the final product from this sequence of reactions.
H3O+
NaOH
CCl3
H2O
HNO3
Sn
H2SO4
HCl
OH
COOH
HO
1.
HNO2
2.
CH2 N
N
N
N
OH
COOH
3.
C
4.
O
O
N
N
OH
NO2
5.
HOOC
47.
N
N
OH
In the reaction below, the product would be
OH
CHO
+ HCN
C
CN
H
1.
3.
5.
48.
a racemate.
a meso compound.
unresolvable.
2.
4.
optically active.
a mixture of diastereomers.
A group which deactivates the benzene ring towards EAS but which directs the incoming group
principally to the ortho and para positions is
1.
3.
5.
-NH2
-NO2
-NHCOCH3
2.
4.
-Cl
-C2H5
49.
What is true for the equilibrium reaction
O
O
cat.
CH3 C OH
1.
2.
3.
4.
5.
50.
2.
4.
Zn and HCl
LiAlH4 and ether
an alkane.
an alcohol.
a carboxylic acid.
2.
4.
an alkylmagnesium halide.
magnesium carbonate.
Which is a practical method for the preparation of iodobenzene?
1.
2.
3.
4.
5.
iodine + benzene + iron
iodine + benzene + UV light
potassium iodide + chlorobenzene
sodium hypoiodite + benzamide
potassium iodide + benzenediazonium ion
Which reaction sequence would be best to prepare 3-chloroaniline from benzene?
1.
3.
5.
54.
Sn and HCl
H2 and Pt
Na and alcohol
RCH2OH
The reaction between carbon dioxide and a Grignard reagent will yield
1.
3.
5.
53.
+ H2O
Which reagent would bring about this transformation?
1.
3.
5.
52.
CH3 C O CH2 CH3
The use of equimolar quantities of CH3OH and CH3COOH will give the greatest yield of
the ester at equilibrium.
Removal of water will increase the amount of ester at equilibrium.
Addition of CH3COOCH3 will cause the formation of equal an equal number of moles of
water.
Application of pressure increases the amount of ester at equilibrium.
Changing the catalyst will affect the position of the equilibrium.
RCOOH
51.
CH3 OH
chlorination, nitration, reduction
2. nitration, chlorination, reduction
nitration, reduction, chlorination
4. nitration, chlorination
nitration, reduction, acetylation, chlorination, hydrolysis
The catalyst used in the halogenation of benzene is
1.
3.
5.
a proton donor.
a Lewis base
a proton acceptor
2.
4.
an electron donor.
a Lewis acid
55.
The reaction of Br2/FeBr3 with benzene to form bromobenzene is know as
1.
3.
5.
56.
acetic acid
iodomethane
ethanol
2.
4.
formaldehyde
ethylene oxide
Phenol
Phenyl methyl ketone
Toluene
2.
4.
Chlorobenzene
Benzene
An explanation of the addition of sodium bisulfite to heptanal and 2-heptanone but not to 3heptanone is
1.
3.
5.
59.
nucleophilic substitution
ionic addition
Which aromatic compound behaves most like benzoic acid when it undergoes reaction with
concentrated nitric acid and sulfuric acid?
1.
3.
5.
58.
2.
4.
Which reagent will lengthen the carbon chain by two carbons in one step when reacted with an
organolithium reagent?
1.
3.
5.
57.
free radical substitution
electrophilic substitution
elimination
steric inhibition of resonance.
2.
steric hinderance.
steric inhibition of solvation.
4.
differences in resonance effects.
the lower dipole moment of 3-heptanone.
Which will undergo a Friedel-Crafts alkylation reaction?
CH3
CH3
OH
CH2
C O
B
C
OH
NO2
A
1.
3.
5.
60.
a, b, c
b and d
c and d
D
2.
4.
a and c
a and b
The reaction of diethylmalonate with sodium ethoxide produces ethanol and a
1.
3.
5.
free radical
molecular species
carboxylate ion
2.
4.
carbocation
carbanion
61.
The principal product of the reaction between methyl butanoate and 2 moles of CH3MgBr after
hydrolysis is
1.
3.
5.
62.
C3H7COCH3
C3H7CHOHCH3
C3H7CH2OH
2.
4.
C3H7C(OH)(CH3)2
C3H7COCH(CH3)2
Which reaction sequence would be best to prepare 1,4-diaminobenzene from benzene
1.
2.
3.
4.
5.
nitration, sulfonation, nitration, hydrolysis, reduction
nitration, reduction, nitration, reduction
nitration, reduction, acetylation, nitration, reduction
nitration, reduction, acetylation, nitration, hydrolysis, reduction
nitration, reduction
Cl
63.
The correct name for
is
Cl
1.
3.
5.
64.
2.
4.
3,5- dichloronaphthalene
1,3- dichloronaphthalene
Which of the following would react most rapidly with sodium ethoxide to produce an ether?
1.
3.
5.
65.
7,9-dichloronaphthalene
2,4- dichloronaphthalene
6,8- dichloronaphthalene
chlorobenzene
p-nitrochlorobenzene
m-chlorotoluene
2.
4.
p-nitrotoluene
m-(chloromethyl)-toluene
Select the final product from this sequence of reactions.
NaOEt
Acetoacetic ester
1.
H3C
O
CH3
C
C
CH3I
CH3CH2CH2Br
NaOEt
CH3
2.
COOC2H5
H3C
CH2CH2CH3
C
CH2COOC2H5
CH2CH2CH3
H
3.
H3C
C
CH2COOC2H5
CH2CH2CH3
CH3
5.
CH3CO
C
CH3
CH2CH2CH3
CH3
4.
CH3CO
C
CH3
CH2COOC2H5
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