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Chem 2300

Exam 2

October 25, 2013

Name:

(first) (last)

Last 4 digits of

A number

Score

I. Multiple Choice

( /30)

/90

II

/10

Total score

/100

Note: Periodic table and pKa Values are on page 13.

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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) 3-methyl-1-vinylcyclohexene

(b) 2-methyl-4-vinylcyclohexene

(c) 1-methyl-3-vinylcyclohexene

(d) 1-methyl-5-vinylcyclohexene

(e) None of the above

2. What is the systematic name for the following compound?

(a) (R)-5-methylcyclohexene

(b) (S)-4-methylcyclohexene

(c) (R)-4-methylcyclohexene

(d) (S)-5-methylcyclohexene

(e) None of the above

3. What is the systematic name for the following compound?

(a) 1-ethyl-1,4-cyclohexadiene

(b) 1-ethyl-1,3-cyclohexadiene

(c) 2-ethyl-1,4-cyclohexadiene

(d) 1-ethyl-1,3-cyclohexadiene

(e) None of the above

4. What is the systematic name for the following compound?

(a) cis-4-methyl-3-hexene

(b) trans-3-methyl-3-hexene

(c) (Z)-3-methyl-3-hexene

(d) (E)-3-methyl-3-hexene

(e) None of the above

5. What is the systematic name for the following compound?

(a) (Z)-2-fluoro-4-methyl-2-heptene

(b) (E)-1-fluoro-4-methyl-2-heptene

(c) (E)-2-fluoro-4-methyl-2-heptene

(d) (Z)-1-fluoro-1,3-dimethyl-1-hexene

(e) None of the above

CH3

CH2CH3

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6. What is the systematic name for the following compound?

(a) (E)-1-bromo-1-fluoro-3-methyl-1-pentene

(b) (Z)-1-fluoro-1-bromo-3-methyl-1-pentene

(c) (E)-1-fluoro-1-bromo-3-methyl-1-pentene

(d) (Z)-1-bromo-1-fluoro-3-methyl-1-pentene

(e) None of the above

7. What is the systematic name for the following compound?

(a) 3-fluorocyclohexene

(b) (Z)-3-fluorocyclohexene

(c) Cis-3-fluorocyclohexene

(d) (R)-3-fluorocyclohexene

(e) None of the above

8. Which of the following compounds have Z configuration (carbon-carbon double bond)?

Cl

I

Br Br

IIIII

HOBr

Cl

IV

O

(a) I, III, IV

(b) I, II, III

(c) I, IV

(d) I, II, III, IV

(e) None of the above

9. What is the correct order of stability for the following alkenes (most to least)?

I II III IVV

(a) I>II>III>IV>V

(b) V>I>III>IV>II

(c) V>I>IV>III>II

(d) V>IV>III>II>I

(e) None of the above

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Based on the potential energy diagram for the following reaction, answer the questions from 10 to 13.

I

II

III

IV

V

potential energy

HCl

A B

C

reaction coordinate

Cl

10. What could best describe the reaction above?

(a) This is a one-step endothermic reaction.

(b) This is a one-step exothermic reaction.

(c) This is a two-step endothermic reaction.

(d) This is a two-step exothermic reaction.

(e) None of the above

11. Which of the following represents the heat of reaction?

(a) A

(b) B

(c) C

(d) A and B

(e) III

12. Which represent the activation energy of the rate-determining step of the reaction?

(a) A

(b) B

(c) C

(d) A and B

(e) II

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13. Which of the following description is correct?

(a) This reaction will lead to the formation of meso compounds.

(b) This reaction will lead to the formation of achiral compounds.

(c) This reaction will lead to the formation of a racemic mixture.

(d) This reaction will lead to the formation of structural isomers.

(e) None of the above

14. What is the systematic name for the following compound?

(a) (R)-4-bromo-2-hexyne

(b) (R)-3-bromo-1-hexyne

(c) (S)-4-bromo-2-hexyne

(d) (S)-3-bromo-1-hexyne

(e) None of the above

15. Arrange these carbocations in order of stability (most to least).?

(a) I>II>III>IV

(b) III>II>I>IV

(c) III>I>II>IV

(d) II>III>I>IV

(e) I>III>II>IV

16. What could be the possible product for the following reaction?

Br

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17. 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 -D-fructofuranose 6-phosphate

(a) They are structural isomer to each other.

(b) They are diastereomer to each other.

(c) They are enantiomer to each other.

(d) They are identical.

(e) None of the above

18. What could be the major product for the following reaction?

HBrmajor product?

(a) Br (b)Br

(c)Br

(d)Br

(e) None of the above

19. What will be the major product in its most stable conformation from the following reaction?

H2

Pd/Cproduct?

(a) (b) (c) (d) (e) None of the above

OH

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20. 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) I, IV

(b) I, II

(c) III, IV

(d) II, III

(e) None of the above

21. Which is a diastereomer to the compound circled in the box?

(a) I

(b) II

(c) III

(d) IV

(e) None of the above

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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 (not chiral amines) are present on Amoxicillin, an antibacterial drug?

(a) 2

(b) 3

(c) 4

(d) 5

(e) 6

24. Which of the following compound is achiral?

(a) I

(b) II

(c) III

(d) IV

(e) None of the above

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25. What are the R and S assignments for carbon 2 (C2) and carbon 3 (C3) of cocaine?

(a) C2 is R and C3 is R.

(b) C2 is R and C3 is S.

(c) C2 is S and C3 is R.

(d) C2 is S and C3 is S.

(e) None of the above

26. Which of the following compound is chiral?

(a) I

(b) II

(c) III

(d) IV

(e) V

27. Ephedrine in its natural form, known as má huáng (麻黄) in traditional Chinese medicine, has been

documented in China since the Han Dynasty (206 BC – 220 AD) as an antiasthmatic and stimulant.

What are the correct R and S assignments that match the given systematic name of ephedrine?

(a) (1R,2S)-2-(methylamino)-1-phenylpropan-1-ol

(b) (1R,2R)-2-(methylamino)-1-phenylpropan-1-ol

(c) (1S,2R)-2-(methylamino)-1-phenylpropan-1-ol

(d) (1S,2S)-2-(methylamino)-1-phenylpropan-1-ol

(e) None of the above

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Terbinafine hydrochloride (commonly marketed as Lamisil) is a synthetic allylamine antifungal from

Novartis. Answer Q.28 based on the following structure and atom-labeling of Lamisil.

28. Which of the following description regarding Lamisil is incorrect?

(a) Lamisil contains a chiral nitrogen atom (N2).

(b) Lamisil contains a chiral carbon atom as C8.

(c) Lamisil contains both cis and trans C=C.

(d) Lamisil contains alkyne functional group.

(e) None of the above.

29. How many chiral carbons are present on sucrose?

(a) 7

(b) 8

(c) 9

(d) 10

(e) 11

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Mupirocin (Bactroban or Centany) is an antibiotic of the monoxycarbolic acid class. It was originally

isolated from Pseudomonas fluorescens NCIMB 10586. Mupirocin is bacteriostatic at low

concentrations and bactericidal at high concentrations. It is used topically and is effective against Gram-

positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA).

30. How many chiral carbons are present on mupirocin?

(a) 7

(b) 8

(c) 9

(d) 10

(e) 11

Continue to the Next Page

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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 (Note: no need to

involve furamase in the mechanism but use H+ as the catalyst.). The resulting malate is in S

configuration (assignment). Draw the specific structure of (S)-malate. (10 points)

Next Page: Periodic Table & pKa Values

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pKa Values for Some organic and Inorganic Acids

Acid Formula pKa Conjugate Base

Ethane CH3CH3 51 CH3CH2-

Ammonia NH3 38 NH2-

Ethanol CH3CH2OH 15.9 CH3CH2O-

Water H2O 15.7 HO-

Ethylammonium ion CH3CH2NH3+

10.64 CH3CH2NH2+

Bicarbonate ion HCO3-

10.33 CO32-

Phenol C6H5OH 9.95 C6H5O-

Ammonium ion NH4+

9.24 NH3

Carbonic acid H2CO3

6.36 HCO3-

Acetic acid CH3CO2H 4.76 CH3CO2-

Benzoic acid C6H5CO2H 4.19 C6H5CO2-

Phosphoric acid H3PO4 2.1 H2PO4-

Hydronium ion H3O+ -1.74 H2O

Sulfuric acid H2SO4 -5.2 HSO4-

Hydrogen chloride HCl -7 Cl-

Hydrogen bromide HBr -8 Br-

Hydrogen iodide HI -9 I-