Oganesyan, Chem-105

Glendale Community College, Fall 2010

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Supplemental Problem Set 6: Synthesis and

Reactions of Alkenes

1. One of the products that results when 1-bromo-2,2-dimethylcyclopentane is heated in ethanol is shown

below. Give a mechanism by which it is formed and give the name of this mechanism.

2. Provide the structure of the major organic product in the following reaction.

3. Which diastereomer of 1-bromo-4-t-butylcyclohexane, the cis or the trans, undergoes elimination more

rapidly when treated with sodium ethoxide? Explain your answer.

4. Provide the structure of the major organic product from following reaction.

Oganesyan, Chem-105

Glendale Community College, Fall 2010

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5. When 1-iodo-1-methylcyclohexane is treated with NaOCH2CH3 as the base, the more highly substituted

alkene product predominates. When KOC(CH3)3 is used as the base, the less highly substituted alkene

predominates. Give the structures of the two products and offer an explanation.

6. What major product results when 2-bromo-2-methylbutane is treated with sodium ethoxide.

7. Based on Zaytsev’s rule, select the most stable alkene.

A) 1,2-dimethylcyclohexene

B) 1,6-dimethylcyclohexene

C) cis-3,4-dimethylcyclohexene

D) They are all of equal stability

8. Based on Zaytsev's rule, select the most stable alkene.

A) 1-methylcyclohexene

B) 3-methylcyclohexene

C) 4-methylcyclohexene

D) They are all of equal stability

Oganesyan, Chem-105

Glendale Community College, Fall 2010

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9. When 3-iodo-3-ethylpentane is treated with sodium methoxide in methanol, the major organic product is

an ______ that is generated through an ______ mechanism.

A) ether, SN1 B) ether, SN2 C) ether, E1 D) alkene, E2 E) alkene, E1

10. Predict the most likely mechanism and the product from the reaction between 2-chloro-2-methylpentane

and sodium ethoxide in ethanol.

11. Which compound produces only one alkene when treated with sodium methoxide?

A) 2-chloro-2-methylpentane

B) 3-chloro-3-ethylpentane

C) 3-chloro-2-methylpentane

D) 2-chloro-4-methylpentane

E) 2-chloro-3-ethylpentane

12. The major product which results when 2-chloro-2-methylpentane is heated in ethanol is an ether. Show

and name the mechanism by which this ether forms.

13. Which of the following mechanisms feature carbocation intermediates?

A) SN1 only

B) SN2 only

C) E1 only

D) E2 only

E) Both SN1 and E1

Oganesyan, Chem-105

Glendale Community College, Fall 2010

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14. Predict the most likely mechanism and the product for the reaction below.

15. Which mechanism(s) give(s) alkenes as the major products, SN1, SN2, E1, or E2?

16. How many distinct alkenes can result from E2 elimination of the compound below? Give their structures

and IUPAC names.

Oganesyan, Chem-105

Glendale Community College, Fall 2010

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17. Provide the structure of the major organic product from the following reaction.

For questions 18-20 draw all alkene products and circle the major product:

18.

19.

20.

Oganesyan, Chem-105

Glendale Community College, Fall 2010

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21. Propose a detailed, step-by-step mechanism for the reaction shown below.

22. Draw all likely products of the reactions below and circle the major product.

For the questions 24-26 provide the reagents for the transformations given:

23.

24.

25.

Oganesyan, Chem-105

Glendale Community College, Fall 2010

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26. Provide the products of these reactions:

CH3

H3C

HBr

H2O

H2SO4

CH3

CH3Br2

H2O

MCPBAH3C

CH3

H3C

H2/Pt

H2O

H2SO4

CH3

1). Hg(OAc)2, H2O

2). NaBH4, OH-

CH2I2

H3C Zn(Cu)

Oganesyan, Chem-105

Glendale Community College, Fall 2010

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H3C

1). O3

H2O

H2SO4

CH3

OsO4

t - BuOOH

CH3CO3H

H3C

2). (CH3)2S

27. Provide the products of the reactions of 1-propylcyclopentene with these reagents:

Br2, CCl4

Br2, H2O

1. BH3/THF, 2. H2O2/OH-

HBr

HBr/Ph-OO-Ph/UV

H2O/ H2SO4

[OsO4], t-BuOOH

1. O3, 2. (CH3)2S

Oganesyan, Chem-105

Glendale Community College, Fall 2010

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28. Provide the alkenes that would give the following products. More than one answer may be possible in

some cases.

Br2, CCl4

1. Hg(OAc)2, H2O

HBr

2. NaBH4, NaOH

Br Br

Ph Ph

HH

OH

Br

1. BH3/THF, 2. H2O2/OH-

H2/Pt

[OsO4], t-BuOOH

OH

H3C

HO OH

CH3

HH

H3C

Oganesyan, Chem-105

Glendale Community College, Fall 2010

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29. Show the mechanism and the reagents for the following reactions. Include stereochemistry when

appropriate.

Cl

Cl

Cl

CH3

Br

OH

H

HO

Br Br

H CH3

HH3C

Oganesyan, Chem-105

Glendale Community College, Fall 2010

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30. Show synthesis of the following compounds from the indicated starting materials. More than one step

might be required.

OHOH

Br

OH

Cl

OH

PhCl Ph

31. Explain which compound has a faster rate of reaction with water under acidic conditions:

NO2

oror

or

or

Oganesyan, Chem-105

Glendale Community College, Fall 2010

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32. Show the reactions that could be used to convert 1-pentene to these products. More than one step might

be required in some cases.

OH

OH

Cl

OHO

Cl

OH

OH

O

H