Département de chimie et science biomoléculaire |...

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Faculté des sciences | Faculty of Science Département de chimie et science biomoléculaire | Department of Chemistry and Biomolecular Sciences Pavillon d’Iorio Hall 10 Marie-Curie Ottawa ON Canada K1N 6N5 ' 613-562-5728 7 613-562-5170 [email protected]

Final Exam – CHM1321-B

Date:___July 4th___________ Length:__3 hrs_____ Last Name: _______________________ Professor ___Sandro Gambarotta_________________________ First Name:________________________ Student #_______________ Seat #

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1. A correct IUPAC name for the following compound is:

OH Cl A) 4-propyl-5-chloro-3-heptanol B) 4-propyl-3-chloro-5-heptanol C) 4-(1-chloropropyl)-3-heptanol D) 5-chloro-4-propyl-3-heptanol E) 3-hydroxy-4-propyl-5-chloroheptane Ans: D

2. Which cycloalkane would you expect to have the smallest heat of combustion? Briefly and schematically explain your reasoning. Ans: cyclohexane

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3. Draw and name all the constitutional isomers for the formula C5H12

Answ:

4. Which of the following molecules is achiral?

CC CH3C

H

H

CH3

Br

FClH

CO2H

OH

OHH

HHO2C

CO2H

CO2H

OHH

HHOBr

CH2CH3

CH3

HO

I II III

IV V Ans: II

n-pentane

isopentane neopentane

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5. Can you identify any enantiomeric pair in the list below?:

CH2CH2CH3

H3C Cl

CH3

CH2CH2CH3

Cl CH3

CH3

I II

H

H3C Cl

CH2CH2CH3

CH2CH2CH3

H H

CH2Cl

IV V

CH2CH2CH3

H3C Cl

H

III

Ans: III, IV

6. The structures

CH3

H CH3H

CH3

H CH3

H

represent: A) a single compound. B) enantiomers. C) meso forms. D) diastereomers. E) conformational isomers. Ans: A

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7. Which structure(s) represent(s) diastereomer(s) of I?

CH3OHHHHO

HO HCH3

I II

CH3OHHHHO

H OHCH3

CH3OHHOHH

H OHCH3

III IV

CH3HHOHHO

H OHCH3

V

CH3OHHOHH

HO HCH3

Ans: II and III

8. Give the proper name to the molecule below (including R,S labels if applicable)

CH2CH3ClH

CH3HCl H

CH3 : Ans: (2S,3R,4S)-2,4-Dichloro-3-methylhexane

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9. An alkene adds hydrogen in the presence of a catalyst to give 3,4-dimethylhexane. Ozonolysis of the alkene followed by treatment with zinc and acetic acid gives a single organic product. Give the structure of the alkene :

Answ:

CH3CH2C=CCH3

CH3

CH2CH3

(cis or trans)

10. Which of the following reagents might serve as the basis for a simple chemical test that would distinguish between pure 1-pentene and pure pentane?

A) Bromine in carbon tetrachloride B) Dilute aqueous potassium permanganate C) Concentrated sulfuric acid D) All of the above E) Answers A) and B) only

Ans: D

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11. What would be the major product of the following reaction?

HCl

IV

I

Cl

Cl

II

Cl

V

Cl

III

ClCl

Ans: II

12. Which compound(s) will be formed by the reaction of Br2/CCl4 with cyclohexene ?

I II III

H

Br

HBr

H

H

BrBr

H

H

BrBr

Ans:

II and III

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13. What would be the major product of the following reaction? Br2, CCl4

I

CH3BrBr

C3H7

HH

CH3BrBr

C3H7

HH

II

CH3BrH

C3H7

HBr

III

C3H7

BrH

CH3

HBr

IV

?

A) Equal amounts of I and II B) Equal amounts of II and III C) Equal amounts of III and IV D) I and II as major products, III and IV as minor products E) All of the above in equal amounts

Ans: A

14. Which alkene would react with cold dilute alkaline permanganate solution to form an optically inactive and irresolvable product?

A)

B)

C)

D)

E)

Ans: C

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15. Select the structure of the major product formed from the following reaction.

Ans: IV

16. The hydroboration-oxidation procedure can be successfully employed for synthesis of deuterated derivatives, by using BD3 instead of BH3. What product would you expect from the following reaction?

Ans:

I

CH3

CH3OH

CH3

OH

CH2OH HO CH3 CH3

OH

I II III IV V

1. Hg(OOCCH3)2 THF, H2O

2. NaBH4, NaOH?

CH3

CH3DHO

H CH3DH

H CH3DBD2

H CH3OHD

H CH3BD2H

D

1. (BD3)2

2. H2O2/NaOH?

+enantiomer

I

+enantiomer

II

+enantiomer

III

+enantiomer

IV

+enantiomer

V

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17. What would be the final product?

Ans:

18. Which would be the best method for converting 3,3-dimethyl-1-pentene into 3,3-dimethyl-2-pentanol?

A) H3O+, heat B) BH3:THF; then H2O2, OH- C) concd. H2SO4; then H2O, heat D) Hg(OAc)2/THF-H2O; then NaBH4,OH- E) HBr; then NaOH/H2O

Ans: D

H3CC CH2

CH3RCOOH

O

product final productCH3OH, HA

(CH3)2CCH2OH

OCH3

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19. What is the product, A, that would be obtained from the following reaction sequence?

A) I B) II C) III D) IV E) V

Ans: C

CH2

O

CH2

CH3CH2MgBr H3O+C CH A

C CCH2CH3 C CCH2CH2OCH2CH3 C CCH2CH2OHCH3CH2

C CCH2CH2OCH3 C COCHCH2CH3

I II III

IV V

CH3

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20. Which of the following structures would be aromatic?

A) I B) II C) III D) IV E) V

Ans: B

IVI II III V

-2

2K

KK Br Br

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21. What would be the major product(s) of the following reaction?

NO2

O

I II III

NO2SO3H

O

NO2

SO3HO

NO2HO3S

OHO3S

NO2

O

IV

?H2SO4

A) I B) II C) III D) Equal amounts of IV E) Equal amounts of II and IV Ans: C

22. Which compound is an acetal?

I

O OH

III

O

O

IV

O OH

II

O OCH3

Ans: II

23. Draw the structure of the compound formed when HCl is added to a solution of pentanal in methanol? Ans: O

O

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24. Draw the mechanism of 1-hexene bromination. See slide show

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