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Chemistry 2213a Final Exam, Fall 2011

1.

Page 1 2

Shown below is the structure of caffeine. How many sp -hybridized carbon atoms are present in caffeine?

O A) 5

H3C

B) 2 C) 3

CH3 N

N

O

N

N

D) 8

CH3

E) 4

2.

Shown below is the structure of aspartame. Which functional group is not present in aspartame? A) Amine

NH2 O

H N

B) Carboxylic acid C) Ester

O

D) Ether

O

OH O

E) Amide

3.

When the amino acid arginine, shown below, is dissolved in acid, which atom is protonated first? A) 1

2

4

NH

5

O

B) 4 C) 5

H 2N

N H

D) 2 E) 3

OH 3

1

NH2

Chemistry 2213a Final Exam, Fall 2011

4.

Page 2

Which one of the following is not 3-ethyl-2-methylpentane?

H A)

CH3 CH2

CH3 CH3

CH3 CH3CH2 B)

H CH2CH3

H

H C)

CH3 CH2 CH3

CH3 D)

H

C

CH3

H

C

CH2 CH3

E)

CH2 CH3

5.

A substituted cyclohexane has all of its substituents cis to each other. When the substituted cyclohexane is in its most stable conformation, all of its substituents are in the equatorial position. How many of the following could be the substituted cyclohexane?    

1,2-Dichlorocyclohexane 1,3,5-Trimethylcyclohexane 1,3,4-Trifluorocyclohexane 1,4-Dimethylcyclohexane

A) 4 B) 2 C) None of them D) 1 E) 3

Chemistry 2213a Final Exam, Fall 2011

6.

Page 3

Which one of the following alkenes undergoes the fastest acid-catalyzed hydration?

B)

A)

C)

Br

D)

E)

OCH 3

OCH 3

7.

Which compound gives the ozonolysis product shown below?

?

O

1. O3

O

2. (CH3) 2S

A)

B)

D)

E)

C)

Chemistry 2213a Final Exam, Fall 2011

8.

Page 4

What is/are the major product(s) of the following reaction?

+ H2

1

2

Pd

3

?

5

4

A) 2 only B) 5 only C) 1 and 2 only D) 2 and 4 only E) 1 and 3 only O

9.

Shown on the right is captopril, a drug used for the treatment of high blood pressure. How many statements about captopril are correct?

N COOH



It contains two S stereocentres



It contains an sp -hybridized nitrogen atom



It contains one amide group



It forms a salt upon treatment with NaOH

3

A) 3 B) 2 C) None are correct D) 1 E) All are correct

SH

Chemistry 2213a Final Exam, Fall 2011

10.

Page 5

Which stereoisomer of lactic acid is different from the other four?

A)

H 3C H

C

C

B)

OH

HOOC

COOH

D)

11.

H H 3C

COOH

CH3

COOH

H OH

C)

OH

C

E) OH

H H 3C

C COOH

Which reactions result in the formation of only one product? 1.

+

+ OsO4

2.

3.

Cl2

+

H2

A) 2 only B) 1 and 3 only C) 1 and 2 only D) 3 only E) All three form only one product

Pt

H

OH CH3

Chemistry 2213a Final Exam, Fall 2011

12.

Page 6

How many stereoisomers are formed in the following reaction?

+ HCl

product(s)

A) 4 B) 2 C) 1 D) 8 E) 6

13.

The two compounds shown on the right can be differentiated by… A) How fast they react with PCC

C C

B) The rotation of plane-polarized light C) The number of signals in their D) IR spectroscopy E) The bromine test

HC C

13

C-NMR spectra

Chemistry 2213a Final Exam, Fall 2011

14.

Page 7

What statements are correct about zingiberene, the major flavouring component of ginger? 1. It is a terpene. 2. It contains three stereocentres. 3. Its 13 C-NMR spectrum contains 12 signals. 4. Its IR spectrum contains a signal at 3100 cm −1. A) All statements are correct B) 1 and 4 only C) 3 and 4 only D) 1 and 2 only E) 2 and 3 only

15.

A cyclic alcohol, C 5H10O, is treated with conc H 2SO4. The 13C-NMR spectrum of the major product contains 3 signals. What is a possible structure of the alcohol?

OH

OH

A)

B)

D)

E)

OH

C)

OH

OH

Chemistry 2213a Final Exam, Fall 2011

16.

Page 8

Choose the best leaving group from the set of three leaving groups, and the best nucleophile from the set of three nucleophiles. Leaving groups: HO

−

Cl

−

−

I

Best leaving group

HO

F

B)

I−

I−

C)

HO

−

−

I

CH4

−

I

Cl

−

−

A)

E)

F

Best nucleophile

−

D)

17.

Nucleophiles: CH 4

CH4

−

I

−

Which one of the following molecules reacts most rapidly with a nucleophile in an SN 2 reaction?

O

Br B)

A)

C)

F D)

E)

I

Cl

Chemistry 2213a Final Exam, Fall 2011

18.

Page 9

Which pair of reagents gives the best yield of elimination products?

A)

O

HO

C)

B)

+ CH3Br

+

O

D)

Br

O

+

Br

+

Br

O E)

+ Br

19.

What is the product of the following reaction? Br

Br

Br

+

NaS

SH

A)

S

E) S

S

B)

S

D)

?

SNa

S S

SH

+ 2 NaBr

C)

S S

Chemistry 2213a Final Exam, Fall 2011

20.

Page 10

Which reaction does not proceed by the mechanism indicated?

A)

Br + HO

by E2

Cl B)

by E1

+ H 2O

Br

C)

O ONa

+

by SN2

O

O

D)

+

HO

Cl

O E)

21.

Br

by S N2

OH

O

+ CH3 OH

O

by S N1

Rank the following compounds in the order of increasing boiling point. OH

OH

1

3

2

Lowest

O

O

4 Highest

A)

1

4

3

2

B)

4

1

2

3

C)

4

1

3

2

D)

1

2

4

3

E)

1

4

2

3

Chemistry 2213a Final Exam, Fall 2011

22.

23.

Page 11

What is the oxidation number of the carbon atom in each of the following compounds?

CH3OH

HCHO

HCOOH

A)

−1

0

+3

B)

−2

0

+2

C)

0

+1

+2

D)

−1

+1

+3

E)

−2

−1

0

What is the product of the following reaction sequence? CH3Br

Na OH

?

OH

A)

O

B)

C) OCH3

D)

Br

E)

Na

CH3 ONa

Chemistry 2213a Final Exam, Fall 2011

Page 12

O

24.

The best reaction sequence for the synthesis of the compound on the right is shown in which one of A–E?

ONa

O

A)

NaHCO3

Cl

O

H3O

OH

O

ONa

B)

+ Cl

OH

OH

C)

O

+

H

Cl

OH

O

D)

+

HO

HO

OH

OH

O

E)

H

SOCl2 OH

Mg ether

OH

Chemistry 2213a Final Exam, Fall 2011

Page 13 2

In how many of the following molecules are all atoms in the ring sp -hybridized?

25.

CH3

CH 3

N O

N

O

A) 4 B) 3 C) 1 D) None E) 2

26.

Which one of A–E is not involved in the mechanism of the following reaction?

+ (CH3 )2CHCl

CH(CH3 ) 2

AlCl 3

A)

B)

D)

E)

C)

CH(CH 3) 2 (CH3) 2 CH

CH(CH 3) 2

CH(CH 3) 2

CH(CH 3) 2

Chemistry 2213a Final Exam, Fall 2011

27.

Page 14

Which one of A–E does not give a good yield of the product shown? O

O

A)

FeBr 3

Br

NO 2

B)

NH2

Pd

+ 3H2

COOH + KMnO 4

C)

Br

28.

D)

+ Br2

E)

+ conc. H 2SO4

SO 3 H

heat

What is a possible structure for a compound with the formula C 7H4NO 2Cl? OH O

A)

N Cl

NH2

N

O

B)

C)

OH

O

NH

E)

D)

N H

HO

Cl Cl

O

OH

O O

Cl

Chemistry 2213a Final Exam, Fall 2011

29.

Page 15

What is a product of the following reaction sequence?

Br

NaOH

NH 2

?

H N

A)

B)

H N

30.

OH

H N

C)

E)

NaO

D)

NaO

NH2

What is the basis behind NMR spectroscopy? That is, NMR relies on… A) The vibrational excitation of bonds B) The rotation of carbon-hydrogen bonds C) The excitation of an electron to an excited state D) The absorption of energy by nuclei E) The disruption of intermolecular forces

Chemistry 2213a Final Exam, Fall 2011

31.

32.

Page 16

Cl

What is the splitting pattern for the indicated protons in the compound shown on the right? 1

2

3

A)

triplet

quartet

triplet

B)

singlet

multiplet

quartet

C)

doublet

triplet

doublet

D)

triplet

multiplet

doublet

E)

triplet

singlet

triplet

CH3CH2CHCH3 1

2

Phenacetin, an analgesic, has the formula C 10H 13NO2 . Its IR and 1H-NMR spectra are shown below. What is its structure?

4000

3000

2000

1500

1000

3

Chemistry 2213a Final Exam, Fall 2011

Page 17

O A)

O

NH2

N H

O

H N

O

C)

O

B)

D)

NHCH3

O

OH NH 2 OCH 3

E) O

33.

Which one of the following adds to a carbonyl group only when an acid catalyst is present? −

A) CH 3

B) CH 3OH −

C) H

D) CH 3S− E) CH 3NH2 34.

Which one of the following is a Grignard reagent? MgBr A)

B) Mg in ether

O D)

CH3 O P O Na OCH3

E)

CH 3NH3 Cl

C)

AlCl 3

Chemistry 2213a Final Exam, Fall 2011

35.

Page 18

The intramolecular reaction between the two circled functional groups of glucose, shown below, forms… HOCH 2

1. A new stereocentre

OH

HO HO

2. An acetal 3. Two enantiomers

OH

CHO

A) 2 only B) 2 and 3 only C) 3 only D) 1 and 2 only E) 1 only

36.

The reductive amination of 3-oxobutanoic acid with methylamine forms which one of A–E?

OH

NHCH 3

O

N A)

B)

O

O

C)

NHCH 3 O

O

D)

OH

O

NHCH3

O

E) HO

NHCH3

Chemistry 2213a Final Exam, Fall 2011

37.

Page 19

Which one of the following is an acetal derived from butanal and isopropanol?

O A)

O

B)

O

O O

C)

D)

O O

E) O

O

O

Chemistry 2213a Final Exam, Fall 2011

38.

Page 20

Which one of A–E does not give a good yield of the product shown?

MgBr A)

COOH

H 3O

+ CO2

O MgBr

B)

+

O + CH3 MgBr

C)

OH

H 3O

H3 O OH

D)

O +

OH

H3 O MgBr

O

HO

E)

+ CH 3MgBr

H3 O

OCH3

Chemistry 2213a Final Exam, Fall 2011

39.

Page 21

Which one of A–E is not involved in the mechanism of the following reaction?

O CH3 COH + CH3 OH

OCH 3 A)

O

H

CH3COCH3

OH 2

H2O CCH 3

B)

OCH 3

OH

C)

CH3COH

CH3COH

OCH 3

OH

D)

CH3 COH

E)

OCH 3

H OCH3

40.

CH3C O H

The cyclization of which one of the following forms an optically inactive  (gamma) lactone? O

O A)

B)

HO

HO

OH

O OH

C)

D)

OH

Cl O

O

E)

HO

OH

Chemistry 2213a Final Exam, Fall 2011

41.

Page 22

How many of the following compounds are named correctly? O

O

O

O

O acetic anhydride

O Na

O Cl

O sodium benzoate

phenyl propanoate

acetyl chloride

A) All are correctly named B) 1 C) 3 D) 2 E) None are correctly named

42.

Rank the following compounds in the order of increasing electrophilicity of the carbonyl carbon. O

O Cl

O NH 2

4

2

O OCH 3

O

1

Low

3 High

A)

3

2

1

4

B)

3

4

1

2

C)

4

1

2

3

D)

2

4

3

1

E)

2

1

3

4

Chemistry 2213a Final Exam, Fall 2011

43.

Page 23

How many of the listed statements are correct about the following reaction? O

O Cl

+ H 2O

OH



The reaction proceeds by an S N2 mechanism.



An acid catalyst is required for the reaction to proceed.



The reaction involves an sp -hybridized carbon atom as an intermediate.



H 2O protonates the carbonyl group before it is attached by OH .

3

A) None are correct B) 2 C) 3 D) 1 E) All are correct

−

Chemistry 2213a Final Exam, Fall 2011

44.

Page 24

What is the product of the following reaction sequence? O Cl2 AlCl3

Mg ether

1. H

O

?

2. H 3O

O O H

A)

H

B)

O O

C)

OH Cl

O

E)

O

D)

Chemistry 2213a Final Exam, Fall 2011

45.

Page 25

Solid anhydrous Na 2SO4 was added to the cyclohexene prepared in Expt #3 before it was further purified by distillation. What was the purpose of adding the solid Na2 SO4 ? A) To encourage the cyclohexene to form crystals B) To remove residual water from the cyclohexene C) To remove coloured impurities from the cyclohexene D) To increase the mass of product obtained E) To prevent further reaction of the cyclohexene

46.

What is the correct formula for calculating the percent yield of a chemical reaction?

A)

grams of product obtained  100% grams of starting materials

B)

theoretical yield of product in moles moles of product obtained

 100%

C)

grams of product obtained  100% theoretical yield of product in grams

D)

grams of starting materials  100% grams of product obtained

E)

m...