Deck 13: Electrophilic Addition to Nonpolar Π Bonds 1: Addition of a Brønsted Acid

Question 1

Which of the following alkenes would be susceptible to a carbocation rearrangement after the electrophilic addition step when treated with HBr?

A)
B)
C)
D)
E)

Answer 1

Question 2

Identify the reagent(s)needed to carry out the reaction below.

A)H₂O
B)HBr
C)H₂O / H₂SO₄
D)H₂SO₄
E)CH₃OH / H₂SO₄

Answer 2

H₂O / H₂SO₄

Question 3

Which of the following would not produce a racemic mixture of enantiomers when treated with HBr?

A)
B)
C)
D)
E)

Answer 3

Question 4

What is the rate-determining step in the reaction shown below?

A)Nucleophilic addition
B)Coordination
C)Proton transfer
D)Electrophilic addition
E)Bimolecular nucleophilic substitution

Question 5

How many possible stereoisomers could be produced in the reaction below?

A)One
B)Two
C)Three
D)Four
E)Six

Question 6

Which of the following is an intermediate in the reaction shown below?

A)
B)
C)
D)
E)

Question 7

Which of the following alkenes would produce the molecule below when treated with DCl?

A)
B)
C)
D)
E)

Question 8

Predict the major product of the reaction below.

A)
B)
C)
D)
E)

Question 9

Which of the following is unlikely to undergo an electrophilic addition reaction?

A)
B)
C)
D)
E)

Question 10

What will be the major product of the reaction below?

A)
B)
C)
D)
E)

Question 11

Which of the following compounds would not produce the same major product as the others when treated with HCl?

A)A
B)B
C)C
D)D
E)E

Question 12

Which of the following contains a nonpolar π bond likely to participate in an electrophilic addition reaction?

A)
B)
C)
D)
E)

Question 13

Which starting material would produce the mixture of products shown below?

A)
B)
C)
D)
E)

Question 14

Predict the major product of the reaction below.

A)
B)
C)
D)
E)

Question 15

Identify the two elementary steps (in order)in the mechanism below.

A)Electrophilic addition, proton transfer
B)Electrophilic elimination, coordination
C)Nucleophilic addition, electrophilic addition
D)Coordination, nucleophilic addition
E)Electrophilic addition, coordination

Question 16

Identify the electron-poor species that participates in the electrophilic addition step in the reaction below.

A)H₂SO₄
B)CH₃CH₂OH₂⁺
C)H₃O⁺
D)CH₃CH₂OH
E)H₃SO₄⁺

Question 17

Which of the following would yield a mixture of constitutional isomers as products when treated with HBr?

A)
B)
C)
D)
E)

Question 18

The electrophilic addition step in the reaction below can result in three carbocation intermediates.Rank these carbocation intermediates in order of increasing stability.

A)2 < 3 < 1
B)2 < 1 < 3
C)1 < 2 < 3
D)3 < 2 < 1
E)1 < 3 < 2

Question 19

Predict the major product of the following reaction.

A)
B)
C)
D)
E)

Question 20

What is the most stable carbocation intermediate that can be formed in the reaction below?

A)
B)
C)
D)
E)

Question 21

Predict the major product of the following reaction and draw the mechanism for the reaction.

Question 22

Briefly explain why the hypothetical reaction below does not occur.

Question 23

Label the electron-rich and electron-poor species in the elementary step below,and draw arrows to complete the mechanism.

Question 24

When the following molecule is treated with acid,it undergoes a reaction yielding a cyclic ether with the molecular formula C₆H₁₂O.Determine the structure of this product,and draw a mechanism to account for its formation.

Question 25

What would be the major product of the following reaction sequence?

A)
B)
C)
D)
E)

Question 26

Draw a complete,detailed mechanism for the reaction below,and determine the structure of the product.

Question 27

Draw a complete,detailed mechanism for the reaction below.Label the electron-rich and electron-poor sites in each step.

Question 28

Which of the following,when treated with HBr,would result in the formation of the same major product at both low and high temperatures?

A)
B)
C)
D)
E)

Question 29

Give an example of a compound containing a nonpolar π bond that would be likely to participate in an electrophilic addition reaction.

Question 30

Draw three different alkenes that would produce the compound below when treated with HBr-one alkene that would undergo a 1,2-hydride shift,one that would undergo a 1,2-methyl shift,and one that would not undergo any carbocation rearrangements.Indicate which one falls into each category.

Question 31

Briefly explain why the hypothetical reaction shown below is unlikely to occur.

Question 32

Predict the major product of the following reaction sequence.

A)
B)
C)
D)
E)

Question 33

What would be the expected major product of the reaction below at a low temperature?

A)
B)
C)
D)
E)

Question 34

Draw the complete,detailed mechanism for the reaction below,and predict the product.Label each elementary step.

Question 35

Which of the following is true regarding the addition of a strong acid to a conjugated diene?

A)The major product formed at low temperatures is the most stable product.
B)The major product formed at high temperatures is the kinetic product.
C)The product of a 1,4-addition is always more stable than the product of a 1,2-addition.
D)The major product formed under thermodynamic control is the most stable product.
E)The major product formed the most rapidly is also the most stable product.

Question 36

Draw all possible products that could be formed in the reaction below,including stereoisomers.

Question 37

Show how the following compound could be synthesized from two different alkenes.

Question 38

Give an example of a compound containing a nonpolar π bond that would be unlikely to participate in an electrophilic addition reaction.

Question 39

Predict the major product of the reaction below,and draw the mechanism for its formation.

Question 40

Draw the most stable carbocation intermediate formed after the electrophilic addition step in the reaction below.

Question 41

Show how you could carry out the following transformation,using more than one reaction if necessary.

Question 42

Fill in the missing starting material needed to complete the reaction below.

Question 43

Draw the major product that would be obtained if the reaction below were run at a high temperature,and draw the mechanism for its formation.

Question 44

Draw the enol intermediate that would be formed in the reaction below.

Question 45

Draw a complete,detailed mechanism for the reaction below,and predict the major product.

Question 46

Draw the major 1,2-addition product and the major 1,4-addition product of the following reaction,and label each.

Question 47

Choose the more stable carbocation intermediate formed in the following step,and explain why it is more stable.

Question 48

Show how the compound below can be synthesized from two different alkenes.

Question 49

Label the thermodynamic product and the kinetic product formed in the reaction below.

Question 50

When certain compounds are treated with HCl,the resulting thermodynamic and kinetic products are identical.Give an example of such a compound.