Deck 6: Properties and Reactions of Haloalkanes: Bimolecular Nucleophilic Substitution

Question 1

What would be the organic product of the following reaction?

A)

B)

C)

D) All of the above.
E) None of the above.

Answer 1

Question 2

What is the major product of the following reaction:

A)

B)

C)

D)

E) no reaction occurs

Answer 2

Question 3

What is the major product of the following two-step reaction?

A)

B)

C)

D)

E) no reaction occurs

Answer 3

Question 4

To which side (if any)would the following equilibrium lie?

A) to the left
B) to the right
C) equally to the right and left
D) there is no way to tell
E) only S_N2,S_N1 and E2 reactions are possible

Question 5

Which of the following reagents would best accomplish a typical S_N2 reaction?

A) CH₃OH
B) H₂O
C) HCN
D) KCN
E) KO^tBu

Question 6

Which of the following haloalkanes would not undergo the reaction below?

A) (CH₃)₂CHI
B) CH₃Cl
C) (CH₃)₃CBr
D) CH₃CH₂Br
E) CH₃CH₂CH₂I

Question 7

What reactants are required to achieve the following transformation?

A)

B)

C)

D)

E) None of the above.

Question 8

What would be the major product of the following reaction?

A)

B)

C)

D)

E)

Question 9

What would be the name of the following?

A) 3,4-dibromo-2-methylhexane
B) 1,2-dibromo-1-isopropylbutane
C) 2,3-dibromohexane
D) 3,4-dibromo-5-methylhexane
E) 3,4-dibromo-3-methylhexane

Question 10

Which of the following would you expect to react fastest with the nucleophile I^- (iodide)?

A) CH₃CH₂CH₂Br
B) CH₃CH₂CH₂Cl
C) (CH₃)₂CHCH₂Br
D) (CH₃)₂CHCH₂Cl
E) (CH₃)₃CCH₂Br

Question 11

Which of the following would you expect to have the weakest C-X bond?

A) CH₃Cl
B) CH₃CH₂Br
C) CH₃F
D) CH₃CH₂I
E) (CH₃)₂CHBr

Question 12

Indicate the reagents required to achieve the following transformation:

A)

B)

C)

D)

E) None of the above.

Question 13

Complete the following reaction:

A)

B)

C)

D)

E) no reaction will occur

Question 14

Which of the following is not normally a good leaving group on carbon?

A) Br
B) OCH₃
C) Cl
D) OSO₂R
E) I

Question 15

Predict the major product of the following reaction:

A)

B)

C)

D)

E) no reaction occurs

Question 16

Several alkyl halides,including iodomethane,are known carcinogens or cancer-suspect materials.To destroy these materials by conversion to non-electrophilic species,you can react them with nucleophiles.Which of the following would be the best for rapidly destroying methyl iodide (iodomethane)?

A) CH₃OH
B) NH₃
C) H₂O
D) NaI
E) CH₃CO₂H

Question 17

What reactants are required to achieve the following transformation?

A)

B)

C)

D)

E)

Question 18

Which of the following would you expect to have the highest boiling point?

A) CH₃CH₂CH₂Br
B) CH₃CH₂CH₂I
C) CH₃CH₂CH₂Cl
D) CH₃CH₂CH₂F
E) CH₃CH₂CH₃

Question 19

Predict the major product of the following reaction:

A)

B)

C)

D)

E) no reaction occurs

Question 20

Predict the major product of the following reaction:

A)

B)

C)

D)

E)

Question 21

Arrange the following in order of increasing nucleophilicity.

A)

B)

C)

D)

E)

Question 22

Predict the major product of the following reaction:

A)

B)

C)

D)

E) None of the above.

Question 23

What is the best way to prepare the compound below?

A)

B)

C)

D)

E) None of the above.

Question 24

Predict the major product of the following reaction:

A)

B)

C)

D)

E) None of the above.

Question 25

Predict the major product of the following reaction:

A)

B)

C)

D)

E) no reaction will occur

Question 26

S_N2 substitution at secondary halides and sulfonates is often complicated by competing E2 elimination.Which of the nucleophiles below would you choose to obtain the highest yield in an S_N2 reaction with menthyl bromide?

A) CH₃ONa
B) CH₃CO₂Na
C) (CH₃)₃N
D) (CH₃)₃COK
E) C₆H₅SNa

Question 27

If the reaction rate of the following reaction is x,doubling the concentration of KCN would give what rate?

A) 2x
B) x/2
C) x²
D) x²/2
E) no change in reaction rate

Question 28

What is the correct stereochemistry of the product of the following reaction:

A) 3R,4S
B) 2S,3R
C) 2R,3S
D) 2R,3R
E) 3R,4R

Question 29

Name the following compound:

A) (1S,2S,5R)-1-bromo-2-isopropyl-5-chlorocyclohexane
B) (1R,2R,5R)-1-bromo-2-isopropyl-5-chlorocyclohexane
C) (1S,3S,4R)-1-chloro-3-bromo-4-isopropylcyclohexane
D) (1S,2S,4R)-2-bromo-4-chloro-1-isopropylcyclohexane
E) (1R,2S,4R)-2-bromo-4-chloro-1-isopropylcyclohexane

Question 30

The curved arrows below represent what type of reaction mechanism?

A) nucleophilic substitution
B) dissociation
C) nucleophilic addition
D) electrophilic addition
E) None of the above.

Question 31

Which of the following can be used to synthesize (R)-2-cyanopentane from (R)-2-bromopentane?

A) NaBr
B) NaCN
C) NaI followed by KCN
D) NaCN followed by HI
E) this reaction cannot occur

Question 32

The Walden Inversion (inversion of configuration)is associated with which of the following?

A) E1 reaction
B) free-radical halogenation
C) S_N1 reaction
D) S_N2 reaction
E) None of the above.

Question 33

Which set of reagents will best accomplish the following reaction?

A) NaBr,acetone
B) H₂SO_4,H₂O
C) Br₂,hv
D) NaOEt,DMSO
E) None of the above.

Question 34

Which of the following statements are true of an S_N2 reaction.

A) follow a first order rate law
B) typically are stereoselective
C) the fastest step is the rate-determining step
D) the carbocation intermediate adopts a trigonal planar geometry
E) all of the above

Question 35

For the following reaction what is the most likely product?

A)

B)

C)

D)

E) no reaction

Question 36

Which of the haloalkanes shown below would react most rapidly with cyanide ion?

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

Question 37

Which of the following is the best leaving group?

A)

B)

C)

D)

E)

Question 38

Which of the following statements best describes why I^- is a better nucleophile than F^- in solution?

A) F^- is a stronger base than I^-.
B) Solvation of F^- impedes its nucleophilicity compared to I^-.
C) I^- is a stronger base than F^-.
D) Solvation of I^- increases its nucleophilicity compared to that of F^-.
E) A and B both offer explanations as to why I^- is a better nucleophile than F^- in solution.