Chapter 4
Chapter 4
4. A correct IUPAC name for the following compound is:
MULTIPLE CHOICE QUESTIONS
Part 4 – Nomenklatur -konformation
(Answers on pages 21-22) Uppgifter markerade * är överkurs
Topic: Nomenclature
1.
A)
B)
C)
D)
E)
OH
The IUPAC name for
6-Ethyl-3,4-dimethylheptane
2-Ethyl-4,5-dimethylheptane
3,4,6-Trimethyloctane
3,5,6-Trimethyloctane
2-(1-Methylpropyl)-4-methylhexane
is:
An IUPAC name for
5-Methyl-4-(1-methylpropyl)hexane
2-Methyl-3-(1-methylpropyl)hexane
2-Methyl-3-(2-methylpropyl)hexane
3-Methyl-4-(1-methylethyl)heptane
5-Methyl-4-(1-methylethyl)heptane
is:
5.
A)
B)
C)
D)
E)
Which of the following pairs of compounds represent pairs of constitutional isomers?
2-Methylbutane and pentane
2-Chlorohexane and 3-chlorohexane
sec-Butyl bromide and tert-butyl bromide
Propyl chloride and isopropyl chloride
All of the above
6. Which of the following is bicyclo[3.2.2]nonane*?
I
3. A correct IUPAC name for the following compound is:
A)
B)
C)
D)
E)
Cl
4-propyl-5-chloro-3-heptanol
4-propyl-3-chloro-5-heptanol
4-(1-chloropropyl)-3-heptanol
5-chloro-4-propyl-3-heptanol
3-hydroxy-4-propyl-5-chloroheptane
Topic: Nomenclature
2.
A)
B)
C)
D)
E)
A)
B)
C)
D)
E)
2,5-Dimethyl-3-propylheptane
3,6-Dimethyl-5-propylheptane
6-Methyl-4-(1-methylethyl)octane
2-Methyl-3-(2-methylbutyl)hexane
3-Methyl-5-(1-methylethyl)octane
A)
B)
C)
D)
E)
I
II
III
IV
V
II
IV
III
V
7. Select the systematic name for
A)
B)
C)
D)
E)
87
Cl
H
H
Cl
cis-1,3-Dichlorocyclopentane
trans-1,4-Dichlorocyclopentane
cis-1,2-Dichlorocyclopentane
trans-1,3-Dichlorocyclopentane
1,1-Dichlorocyclopentane
88
Chapter 4
9.
A)
B)
C)
D)
E)
Chapter 4
Which isomer of C5H10 would you expect to have the smallest heat of combustion*?
Cyclopentane
Methylcyclobutane
1,1-Dimethylcyclopropane
cis-1,2-Dimethylcyclopropane
trans-1,2-Dimethylcyclopropane
Topic: Nomenclature
18.
A)
B)
C)
D)
E)
trans-1,2-Dibromocyclohexane is represented by structure(s):
I
II
III
II and III
I and II
19.
A)
B)
C)
D)
E)
cis-1,2-Dibromocyclohexane is represented by structure(s):
I
II
III
II and III
I and II
12. What is the common name for this compound?
Br
A)
B)
C)
D)
E)
Isobutyl bromide
tert-Butyl bromide
Butyl bromide
sec-Butyl bromide
Bromo-sec-butane
20. cis-1,3-Dibromocyclohexane is represented by structure(s):
13. A correct IUPAC name for the following compound is:
Br
3,6,7-trimethyl-4-bromo-1-octene
4-bromo-3-methyl-6-isopropyl-1-heptene
4-bromo-3,6,7-trimethyl-1-octene
4-bromo-6-isopropyl-3-methyl-1-heptene
Use the following to answer questions 18-19:
Br
H
H
Br
Br
H
H
I
Br
Br
H
Br
H
II
III
89
H
Br
Br
H
A)
B)
C)
D)
Br
H
H
I
H
Br
H
Br
Br
II
III
A)
B)
C)
D)
E)
I
II
III
II and III
I and II
21.
A)
B)
C)
D)
E)
CH3CHCH2!
CH2CH3 is:
An IUPAC name for the group
Isopentyl
Isoamyl
sec-Butylmethyl
2-Methylbutyl
2-Ethylpropyl
22.
A)
B)
C)
D)
E)
The neopentyl group has the alternative name:
1,1-Dimethylpropyl
1,2-Dimethylpropyl
2,2-Dimethylpropyl
1-Methylbutyl
2-Methylbutyl
90
Chapter 4
23.
A)
B)
C)
D)
E)
Chapter 4
28. What is the correct IUPAC name for the following compound?
Br
Cl is:
The correct IUPAC name for
2-Bromo-4-chloro-4-isopropylpentane
4-Bromo-2-chloro-2-isopropylpentane
5-Bromo-3-chloro-2,3-dimethylhexane
2-Bromo-4-chloro-4,5-dimethylhexane
2-(2-Bromopropyl)-2-chloro-3-methylbutane
24. Which of the following is a correct name which corresponds to the common name tertpentyl alcohol*?
A) 2,2-Dimethyl-1-propanol
B) 2-Ethyl-2-propanol
C) 2-Methyl-2-butanol
D) 3-Methyl-1-butanol
E) Methyl tert-butanol
Topic: Nomenclature
25. The correct IUPAC name for the following compound is:
OH
HO
A)
B)
C)
D)
E)
3-Hydroxymethylheptane
3-Hydroxymethylhexane
3-Methyloxyheptane
2-Ethyl-1-hexanol
2-Ethyl-1-heptanol
30.
A)
B)
C)
D)
E)
Which of these is the common name for the 1,1-dimethylpropyl group*?
tert-Butyl
tert-Pentyl
Isopentyl
Neopentyl
sec-Pentyl
31. Neglecting stereochemistry, which of these common group names is ambiguous, i.e.,
does not refer to one specific group*?
A) Butyl
B) sec-Butyl
C) tert-Pentyl
D) Neopentyl
E) sec-Pentyl
32. What is the correct IUPAC name for the following compound?
OH
A)
B)
C)
D)
E)
1-Hydroxy-3-sec-butylcyclopentane
3-sec-Butyl-1-cyclopentanol
1-sec-Butyl-3-cyclopentanol
4-sec-Butyl-1-cyclopentanol
3-Isobutyl-1-cyclopentanol
26. What is a correct name for the following compound?
A)
B)
C)
D)
E)
A)
B)
C)
D)
E)
5-Ethyl-3-methylhexanol
5-Ethyl-3-methyl-1-hexanol
2-Ethyl-4-methyl-6-hexanol
3,5-Dimethyl-7-heptanol
3,5-Dimethyl-1-heptanol
3-Isobutyl-2-methylheptane
3-sec-Butyl-2-methyloctane
5-Isobutyl-6-methylheptane
2-Ethyl-3-isopropyloctane
4-Isopropyl-3-methylnonane
91
92
Chapter 4
33. Isopentyl is the common name for which alkyl group?
A) CH3CH2CH2CH
Chapter 4
36. What is the correct IUPAC name for the following compound?
CH3
B) CH3CH2CHCH2
HO
A)
B)
C)
D)
E)
CH3
C) CH3CHCH2CH2
CH3
D) CH3CH2CH
E)
CH3
CH2CH3
3-Hydroxymethyl-2-heptene
2-(1-methylethyl)-4-hexen-1-ol
5-(1-methylethyl)-2-hexen-6-ol
5-isopropyl-2,6-hexenol
2-(1-methylethyl)-4-hepten-1-ol
37. What is the correct IUPAC name for the following compound?
OH
CH3CCH2
F
CH3
A)
B)
C)
D)
E)
34.
A)
B)
C)
D)
E)
An IUPAC name for
3-Isobutyl-2,4-dimethylhexane
3-sec-Butyl-2,5-dimethylhexane
4-sec-Butyl-2,5-dimethylhexane
4-Isopropyl-2,5-dimethylheptane
4-Isopropyl-3,6-dimethylheptane
is:
5-Ethyl-3-fluorohexanol
5-Ethyl-3-fluoro-1-hexanol
2-Ethyl-4-fluoro-6-hexanol
3-fluoro-5-methyl-7-heptanol
3-fluoro-5-methyl-1-heptanol
38. A correct name for the following compound is:
Cl
A)
B)
C)
D)
E)
3-chloro-8-methylbicyclo[4.3.0]nonane
8-Methyl-3-chlorobicyclo[4.3.1]nonane
3-Methyl-7-chlorobicyclo[4.3.0]nonane
3-Methyl-7-chlorobicyclo[4.3.1]decane
3-chloro-8-methyl[4.3.0]bicyclononane
35. An IUPAC name for the following compound is:
A)
B)
C)
D)
E)
4-Isobutyl-3,4-dimethylheptane
4-sec-Butyl-2,4-dimethylheptane
2,4,5-Trimethyl-4-propylheptane
3,4,6-Trimethyl-4-propylheptane
4-Isobutyl-4,5-dimethylheptane
93
94
Chapter 4
Chapter 4
Topic: Conformational Analysis
Topic: Ring Strain 41-47
40. The least stable conformation of butane is:
H
H3C
H
H
H
H3C
H
CH3
CH3
H
H
H
H
I
CH3
H3C
CH3
H
CH3
H
CH3
H
IV
CH3
A)
B)
C)
D)
E)
H
H
IV
V
A)
B)
C)
D)
E)
I
II
III
IV
V
41.
A)
B)
C)
D)
E)
The preferred conformation of cis-3-tert-butyl-1-methylcyclohexane is the one in which:
the tert-butyl group is axial and the methyl group is equatorial.
the methyl group is axial and the tert-butyl group is equatorial.
both groups are axial.
both groups are equatorial.
the molecule exists in a boat conformation.
V
I
II
III
IV
V
I
CH3
H
H
H3C
H
H
CH3
CH3
H3C
I
II
III
H
CH3
H3C
H
CH3
H3C
H
IV
CH3
H
II
IV
III
V
A)
B)
C)
D)
E)
I
II
III
IV
V
45.
A)
B)
C)
D)
E)
Which isomer would have the largest heat of combustion*?
Propylcyclopropane
Ethylcyclobutane
Methylcyclopentane
Cyclohexane
Since they are all isomers, all would have the same heat of combustion.
H
H
I
II
III
IV
V
III
44. Which cycloalkane has the lowest heat of combustion per CH2 group*?
42. What structure represents the most stable conformation of cis-1,3-dimethylcyclohexane?
A)
B)
C)
D)
E)
II
III
H
H
I
H
H
II
H
43. Which cycloalkane has the largest heat of combustion per CH2 group*?
H
V
95
96
Chapter 4
46.
A)
B)
C)
D)
E)
47.
A)
B)
C)
D)
E)
Chapter 4
Which is the most stable conformation of cyclohexane?
Chair
Twist
Boat
One-half chair
Staggered
50. The most stable conformation of 2,3-dibromobutane, viewed through the C-2—C-3
bond :
CH3
Br
Br
I
H3C
H3C
48. The most stable conformation of butane is:
H3C
H
H
A)
B)
C)
D)
E)
H
H
H
H 3C
H
CH3
CH3
H
H
I
I
II
III
IV
V
H
H 3C
II
H
CH3
H
H
H
H
H
III
IV
CH3
CH3
H
CH3
H
CH3
H
A)
B)
C)
D)
E)
CH3
H
III
Br
H
H
H
H3C
Br
H
Br
CH3
IV
V
H
V
51. The most stable conformation of 3-bromo-2-methylpentane, viewed through the
C-3—C-4 bond (i.e., C-3 in the front, C-4 in the back):
CH3
Br
49. The most stable conformation of 1,2-dibromoethane is:
H
Br
H
Br
H
H
I
II
III
IV
V
Br
I
II
III
IV
V
H
A)
B)
C)
D)
E)
Br
II
Br
Topic: Conformational Analysis
H
H3C
Br
Br
H3C
H3C
H
CH3
Which cycloalkane has the greatest ring strain?
Cyclopropane
Cyclobutane
Cyclopentane
Cyclohexane
Cycloheptane
H
H
H
H
I
H
H
H
Br
Br
H
H
H
Br
H
Br
H
Br
Br
H
H
Br
H
H
H
H
H
III
IV
V
97
III
CH3
Br
CH(CH3)2
H
I
II
III
IV
V
CH3
CH(CH3)2
II
H
A)
B)
C)
D)
E)
Br
H
H
Br
II
H
CH3
CH(CH3)2
H
H
H
CH(CH3)2
I
Br
H
H
Br
H
H
H
CH3
H
CH3
CH2CH3
IV
V
98
Chapter 4
Chapter 4
52. The most stable conformation of 3-bromo-2-methylpentane, viewed through the
C-2—C-3 bond (i.e., C-2 in the front, C-3 in the back):
H
H
CH3
Br
CH3
H
Br
H
H
H3C
CH3
H
CH3
CH2CH3
I
H
CH3
CH(CH3)2
II
III
CH3
CH3
Br
Br
CH2CH3
H
H
CH3
H
55. The most stable conformation of cis-1-tert-butyl-2-methylcyclohexane is the one in
which:
A) the tert-butyl group is axial and the methyl group is equatorial.
B) the methyl group is axial and the tert-butyl group is equatorial.
C) both groups are axial.
D) both groups are equatorial.
E) the twist boat conformation is adopted.
CH2CH3
V
53. The most stable conformation of 2,3-dimethylpentane, viewed through the
C-2—C-3 bond (i.e., C-2 in the front, C-3 in the back):
CH3
H
CH3
CH2CH3
CH2CH3
H
H
H3C
I
H
CH3
H
H
CH(CH3)2
II
CH3
H
H3CH2C
A)
B)
C)
D)
E)
CH3
CH3
H
CH3
CH3
III
H3C
H
CH3
CH3
CH(CH3)2
IV
V
H
H
CH3
I
II
III
IV
V
99
Which cycloalkane has the least ring strain?
Cyclopropane
Cyclobutane
Cyclopentane
Cyclohexane
Cycloheptane
Topic: Conformational Analysis
I
II
III
IV
V
H
54.
A)
B)
C)
D)
E)
H
CH3
IV
A)
B)
C)
D)
E)
Br
Topic: Ring Strain
56. The most stable conformation of trans-1-tert-butyl-2-methylcyclohexane is the one in
which:
A) the tert-butyl group is axial and the methyl group is equatorial.
B) the methyl group is axial and the tert-butyl group is equatorial.
C) both groups are axial.
D) both groups are equatorial.
E) the molecule is in the half chair conformation.
57. The most stable conformation of trans-1-tert-butyl-3-methylcyclohexane is the one in
which:
A) the tert-butyl group is axial and the methyl group is equatorial.
B) the methyl group is axial and the tert-butyl group is equatorial.
C) both groups are axial.
D) both groups are equatorial.
E) the twist boat conformation is adopted.
58.
A)
B)
C)
D)
E)
In the most stable conformation of cis-1,4-dimethylcyclohexane, the methyl groups are:
one axial, one equatorial.
both axial.
both equatorial.
alternating between being both axial and both equatorial.
None of the above
100
Chapter 4
H
H
OH
H
62. Consider the graph below, which is a plot of the relative energies of the various
conformations of hexane, viewed through the C2-C3 bond. The conformations
corresponding to the 60o and 300o are:
Relative energy
59. The most stable conformation for 1,2-ethanediol (ethylene glycol) is shown below. It is
the most stable conformation because:
Chapter 4
OH
H
A)
B)
C)
D)
E)
this corresponds to an anti conformation.
in general, gauche conformations possess the minimum energy.
it is stabilized by intramolecular hydrogen bonding.
it is a staggered conformation.
it has the highest energy of all the possibilities.
0o
60. The graph below is a plot of the relative energies of the various conformations of:
60o 120o 180o 240o 300o 360o
Relative energy
Ethane
Propane
Chloroethane
1-Chloropropane (C1-C2 rotation)
Butane (C1-C2 rotation)
Relative energy
61. The graph below is a plot of the relative energies of the various conformations of:
0o
0o
A)
B)
C)
D)
E)
60o 120o 180o 240o 300o 360o
Angle of rotation
A)
B)
C)
D)
E)
Eclipsed
Staggered, and gauche
Staggered and anti
More stable than the conformation at 180o
None of the above
63. Consider the graph below, which is a plot of the relative energies of the various
conformations of 2,3-dimethylbutane, viewed through the C2-C3 bond. The
conformations corresponding to the 120o and 240o are:
Angle of rotation
A)
B)
C)
D)
E)
Angle of rotation
A)
B)
C)
D)
E)
Relative energy
0o
60o 120o 180o 240o 300o 360o
2-chloropropane
1,3-dichloropropane
2-methylpropane
Butane (C1-C2 rotation)
Butane (C2-C3 rotation)
Ans: E
101
60o 120o 180o 240o 300o 360o
Angle of rotation
Eclipsed, more stable than the conformation at 0o
Eclipsed, more stable than the conformation at 180o
Staggered, more stable than the conformation at 0o
Staggered, less stable than the conformation at 180o
Two of the above are true
102
Chapter 4
Chapter 4
Topic: Conformational Analysis
67. Which of the following can be described as trans isomers?
64. Which conformation of trans-1-isopropyl-3-methylcyclohexane would be present in
greatest amount at equilibrium?
A) The conformation with the methyl group equatorial and the isopropyl group axial
B) The conformation with the methyl group axial and the isopropyl group equatorial
C) The conformation with both groups axial
D) The conformation with both groups equatorial
E) The twist boat conformation.
65. Which conformation represents the most stable conformation of trans-1-bromo-4methylcyclohexane?
CH3
Br
Br
I
A)
B)
C)
D)
E)
Br
II
CH3
CH3
Br
CH3
H3C
Br
IV
III
Br
HO
Cl
Br
I
A)
B)
C)
D)
E)
II
F
CH3
CH3
CH3
HO
III
CH2CH3
IV
V
I
II, V
III, IV
I, III and IV
None of the above are trans isomers.
Topic: Conformational Analysis
68. Which of the following will have the same energy after undergoing ring flip?
V
I
II
III
IV
V
OH
HO
I
Topic: Cis-Trans Isomers
Cl
Br
II
CH3
CH3
CH2CH3
HO
CH2CH3
F
III
A)
B)
C)
D)
E)
I
II
III
IV
V.
69.
A)
B)
C)
D)
E)
The least stable conformation of cyclohexane is the:
boat.
twist boat.
chair.
half-chair.
twist chair.
IV
V
66. Which of the following can be described as cis isomers?
Br
HO
I
A)
B)
C)
D)
E)
Cl
Br
II
CH3
F
III
I
II, V
III, IV
I, III and IV
None of the above are cis isomers.
CH3
CH3
HO
CH2CH3
IV
V
70. Express, quantitatively, the difference in stability of the two structures shown below.
CH3
CH3
H3C
I
A)
B)
C)
D)
E)
103
H3C
II
I is more stable than II by 7.5 kJ mol-1.
I is more stable than II by 15 kJ mol-1.
II is more stable than I by 7.5 kJ mol-1.
II is more stable than I by 15 kJ mol-1.
The two are equal in stability.
104
Chapter 4
Chapter 4
Topic: Conformational Analysis
71.
A)
B)
C)
D)
E)
The twist boat conformation is the preferred conformation for this compound.
cis-1,4-Di-tert-butylcyclohexane
trans-1,4-Di-tert-butylcyclohexane
cis-1,3-Di-tert-butylcyclohexane
trans-1,2-Di-tert-butylcyclohexane
None of these
Topic: Ring Strain
72. Which of these C10H18 isomers is predicted to be the most stable?
I
A)
B)
C)
D)
E)
Topic: Alkane Synthesis, Nomenclature
77. Catalytic hydrogenation of which of the following will yield 2-methylpentane?
A) 2-methyl-1-pentene
B) 2-methyl-2-pentene
C) 4-methyl-2-pentene
D) 4-methyl-1-pentene
E) All of the above
II
III
2
H
H
H
H
IV
V
I
II
III
IV
V
Ans: E
Topic: General
75.
A)
B)
C)
D)
E)
How many constitutional isomers are possible for the formula C6H14?
2
3
4
5
6
76. How many compounds with the formula C7H16 (heptanes) contain a single 3° carbon
atom?
A) 2
B) 3
C) 4
D) 5
E) 6
105
Topic: Alkane Synthesis, Nomenclature
78. The synthesis of an alkyne precursor to 2,2-dimethylheptane is accomplished most
effectively by the reaction between these two reagents:
A) CH3CH2CH2C!CNa and (CH3)3CBr
B) CH3CH2C!CNa and (CH3)3CCH2Br
C) (CH3)3CC!CNa and CH3CH2CH2Br
D) (CH3)3CCH2CH2C!CH and CH3CH2I
E) HC!CNa and (CH3)3CCH2CH2Br
79. The reaction of the Na salt of 3-methyl-1-pentyne with 1-bromo-3-methylbutane
produces which of these?
A) 3,8-dimethyl-4-nonyne
B) 2,7-dimethyl-4-nonyne
C) 3,8-dimethyl-5-nonyne
D) 3,7-dimethyl-4-nonyne
E) 3,7-dimethyl-5-nonyne
Topic: General
80. What is the simplest alkane, i.e., the one with the smallest molecular weight, which
possesses primary, secondary and tertiary carbon atoms?
A) 2-Methylpropane
B) 2-Methylbutane
C) 2-Methylpentane
D) 3-Methylpentane
E) 2,2-Dimethylbutane
81.
A)
B)
C)
D)
E)
How many alkanes of formula C7H16 possess a quaternary carbon atom?
1
2
3
4
5
106
Chapter 4
Svar Part 4 - Nomenklatur, konformation
SHORT ANSWER QUESTIONS
Topic: Nomenclature
92. Give the IUPAC name corresponding to the following structure.
Br
OH
93. Give the IUPAC name corresponding to the following structure:
Br
HO
94.
Chapter 4
Give the IUPAC name corresponding to the following structure:
Br
F
95. Give the IUPAC name corresponding to the following structure:
HO
96. Draw the bond-line structural formula corresponding to the most stable conformation of
the following substance: trans-1-bromo-3-(1-methylpropyl)cyclohexane
97. Draw the bond-line structural formula corresponding to the name: 2,5,9-trimethyl-2decen-7-yne
Topic: Alkane Conformations
98. Draw the Newman projection formula for the gauche conformation of the C2-C3 bond
in pentane.
99. Draw the Newman projection formula for the most stable conformation of the C2-C3
bond in 3-methylpentane.
107
Fråga
1
2
3
4
5
6
7
8
9
10
11
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22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
Svar
C
D
E
D
E
C
D
D
A
A
D
A
C
A
D
E
A
D
A
A
D
C
C
C
B
E
C
D
E
B
E
E
C
D
C
B
E
A
E
B
Rätt/Fel
Fråga
41
42
43
44
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47
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62
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65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
Svar
D
B
A
D
A
A
A
C
C
C
A
E
D
D
B
D
B
A
C
D
E
B
A
B
A
B
C
E
D
A
A
E
A
A
D
C
E
C
A
B
C
108
Rätt/Fel
Chapter 4
Svar
92.
93.
94.
95.
96:
Part 4 – Nomenklatur, konformation forts.:
5-bromo-6-cyclopentyl-2-hexanol
3-(2-bromobutyl)cyclopentanol
trans-1-bromo-2-fluorocyclohexane
3-ethyl-6,7-dimethyl-2-octanol
Br
97:
98:
CH3
H
H
99:
H
H
CH3
H
H
CH2CH3
CH3
H
CH2CH3
109