Chem 2300
Exam 2
October 24, 2014
Name:
(Please print)
(first)
(last)
Last 4 digits of
A number
Score
I. Multiple Choice
(
/90
/30)
II
/10
III
/10
Total score
/110
Note: Periodic table and pKa Values are on page 14.
1
I. Multiple choice questions. (3 points each). Please put your answers on Scantron sheet. Your score will
be graded based only on your answers from Scantron sheet.
1. What is the systematic name for the following compound?
(a)
(b)
(c)
(d)
(e)
(R)-5-methylcyclohexene
(S)-4-methylcyclohexene
(R)-4-methylcyclohexene
(S)-5-methylcyclohexene
None of the above
2. What is the systematic name for the following compound?
(a)
(b)
(c)
(d)
(e)
(S)-3-fluorocyclohexene
(Z)-3-fluorocyclohexene
Cis-3-fluorocyclohexene
(R)-3-fluorocyclohexene
None of the above
3. What is the IUPAC name for the following compound?
(a)
(b)
(c)
(d)
(e)
(R)-4-isopropyl-1-methyl-1-cyclohexene
(S)-4-isopropyl-1-methyl-1-cyclohexene
(S)-4-isopropyl-1-methylcyclohexene
(S)-5-isopropyl-1-methylcyclohexene
None of the above
4. What is the IUPAC name for the following compound?
(a)
(b)
(c)
(d)
(e)
(R)-5-chloro-3-methyl-1-pentyne
(S)-5-chloro-3-methyl-1-pentyne
(R)-1-chloro-3-methyl-4-pentyne
(S)-1-chloro-3-methyl-4-pentyne
None of the above
Cl
5. What is the correct order of stability for the following alkenes (most to least)?
(a)
(b)
(c)
(d)
(e)
I>II>III>IV>V
II>I>III>IV>V
III>II>I>IV>V
V>IV>III>II>I
None of the above
2
6. What could be the major product for the following reaction?
(a)
(b)
(c)
(d)
(e)
II, III
I, V
I, II, III, V
II, III, IV
None of the above
7. Which of the following are pairs of resonance structures?
(a)
(b)
(c)
(d)
(e)
II, IV
I, II, III
III, IV
II, III, IV
None of the above
8. Arrange these carbocations in order of stability (most to least).?
(a)
(b)
(c)
(d)
(e)
I>II>III>IV
III>II>I>IV
III>I>II>IV
II>III>I>IV
I>III>II>IV
3
9. The second reaction in glycolysis involves the conversion of -D-glucopyranose 6-phosphate (I) to D-fructofuranose 6-phosphate (II) under the catalysis of phosphoglucoisomerase. Which of the
following can best describe the relationship between compound I and II?
-D-glucopyranose 6-phosphate
(a)
(b)
(c)
(d)
(e)
-D-fructofuranose
6-phosphate
They are structural isomer to each other.
They are diastereomer to each other.
They are enantiomer to each other.
They are identical.
None of the above
10. What could be the major product for the following reaction?
HBr
major product?
Br
Br
(a)
Br
Br
(c)
(b)
(d)
(e) None of the above
11. What will be the major product in its most stable conformation from the following reaction?
H2
Pd/C
(a)
product?
(b)
(c)
(d)
OH
4
(e) None of the above
12. Brominated vegetable oil (BVO) has been used to stabilize citrus-flavored soft drinks since 1931. Its
high density helps the droplets of natural fat-soluble citrus flavors stay suspended in the drink. BVO can
be prepared by reacting vegetable oil, which contains unsaturated fatty acid, such as oleic acid, with
bromine. Without specifying the R group for the following representative structure of vegetable oil,
what will be the products from bromination?
(a)
(b)
(c)
(d)
(e)
I, IV
I, II
III, IV
II, III
None of the above
13. Which of the following does not represent a pair of stereoisomer?
(a)
and
(b)
H3C
CH3
and
H3C
CH3
HO
(d)
(c)
and
and
OH
(e) None of the above
14. Which of the following can best describe the relationship between compound I and II?
(a)
(b)
(c)
(d)
(e)
They are structural isomer to each other.
They are diastereomer to each other.
They are enantiomer to each other.
They are conformational isomers to each other.
None of the above
5
15. Which of the following compound is a meso compound?
OH
OH
OH
H3C
H3C
HO2C
CO2H
OH
(a)
(b)
(c)
(d)
(e)
HO2C
CO2H
CO2H
OH
OH
I
OH
OH
III
II
I
II
III
IV
None of the above
16. Which of the following compound does not contain any chiral carbon?
(a)
(b)
(c)
(d)
(e)
I
II
III
IV
None of the above
17. Which of the following are pairs of resonance structures?
(a)
(b)
(c)
(d)
(e)
I, II, III, IV
I, II, III, V, VI
I, II, III, IV, V, VI
I, III, IV, V
None of the above
6
CO2H
IV
18. Which of the following statements regarding the acidity of protons highlighted in bold are true?
(a)
(b)
(c)
(d)
(e)
I, II, IV
I, II, III
I, III, IV
II, III, IV
None of the above
19. Which is a diastereomer to the compound circled in the box?
(a)
(b)
(c)
(d)
(e)
I
II
III
IV
None of the above
7
20. Which of the following statements are true?
(a)
(b)
(c)
(d)
(e)
I, II, III, IV, V
I, II, III, V
I, III, IV
I, IV
None of the above
21. Which is a enantiomer to the compound circled in the box?
(a)
(b)
(c)
(d)
(e)
I
II
III
IV
None of the above
8
22. Coniine is a poisonous alkaloid found in poison hemlock and the yellow pitcher plant as a mixture of
R and S isomers. One method to separate the R and S coniine is by addition of a chiral acid and
separation of the salt of diastereomers by recrystalization, a process called resolution.
Which of the following acid can be used to achieve the separation of R and S coniine?
23. How many chiral carbons are present on sucrose?
(a)
(b)
(c)
(d)
(e)
7
8
9
10
11
24. Which compound has the most acidic proton highlighted in bold?
H
H
H
II
I
(a)
(b)
(c)
(d)
(e)
H
III
I
II
III
IV
None of the above
9
IV
25. What is order of decreasing acidity for the following carboxylic acids? (from the most to the least)
CO2H
CO2H
CO2H
O2N
H3C
H3CO
III
II
I
CO2H
CO2H
CO2H
O
Br
V
IV
(a)
(b)
(c)
(d)
(e)
VI
CH3
III>IV>V>VI>I>II
III>I>IV>V>II>VI
III>V>IV>VI>II>I
III>V>II>VI>IV>I
None of the above
26. Which of the following compounds are aromatic compounds?
(a)
(b)
(c)
(d)
(e)
II, VI, VII
I, IV, VII, VIII
II, III, VI, VII
II, IV, V, VIII
None of the above
27. What is the correct order of decreasing reactivity (fastest to slowest) toward the electrophilic
aromatic substitution for the following compounds?
CH3
CO2H
OCH3
II
I
(a)
(b)
(c)
(d)
(e)
III
I>II>III>IV
II>I>IV>III
III>II>IV>I
IV>III>II>I
None of the above
10
IV
28. Aspirin can be prepared from salicyclic acid. What is the IUPAC (systematic) name of salicyclic
acid?
(a)
(b)
(c)
(d)
(e)
o-hydroxyphenoic acid
o-hydroxybenzoic acid
m-hydroxybenzoic acid
m-hydroxyphenoic acid
None of the above
Based on the following synthetic scheme, answer question 29 – 30.
29. What could be reagent A?
(a)
(b)
(c)
(d)
(e)
CH3COCl/AlCl3
Cl2/FeCl3
H2CrO4, H+, heating
HNO3/H2SO4
None of the above
30. What could be reagent B?
(a)
(b)
(c)
(d)
(e)
CH3COCl/AlCl3
Cl2/FeCl3
H2CrO4, H+, heating
HNO3/H2SO4
None of the above
Continue to the Next Page
11
II. The 7th reaction in citric acid cycle is the conversion of furamate into malate, a hydration reaction
catalyzed by furamase. Provide an electron-pushing mechanism for this reaction and explain why H+
functions as a catalyst (Note: no need to involve furamase in the mechanism). The resulting malate is in
S configuration (assignment). Draw the specific structure of (S)-malate. (10 points)
Continue to the Next Page
12
III. (Bonus) Propose an electron-pushing mechanism for the formation of compound II from I. (10
points)
Next Page: Periodic Table & pKa Values
13
pKa Values for Some organic and Inorganic Acids
Acid
Formula
pKa
Conjugate Base
Ethane
CH3CH3
51
CH3CH2Ammonia
NH3
38
NH2Ethanol
CH3CH2OH
15.9
CH3CH2OWater
H2O
15.7
HO+
Ethylammonium ion
CH3CH2NH3
10.64
CH3CH2NH2+
Bicarbonate ion
HCO310.33
CO32Phenol
C6H5OH
9.95
C6H5OAmmonium ion
NH4+
9.24
NH3
Carbonic acid
H2CO3
6.36
HCO3Acetic acid
CH3CO2H
4.76
CH3CO2Benzoic acid
C6H5CO2H
4.19
C6H5CO2Phosphoric acid
H3PO4
2.1
H2PO4Hydronium ion
H3O+
-1.74
H2O
Sulfuric acid
H2SO4
-5.2
HSO4Hydrogen chloride
HCl
-7
ClHydrogen bromide
HBr
-8
BrHydrogen iodide
HI
-9
I-
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