Deck 20: Halogenoalkanes: Substitution and Elimination Reactions

Question 1

Match the chemical descriptors to the following molecules:

-Weak electrophile

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

Answer 1

A

Question 2

Match the chemical descriptors to the following molecules:

-Strong electrophile

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

Answer 2

B

Question 3

Match the chemical descriptors to the following molecules:

-Weak nucleophile

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

Answer 3

C

Question 4

Match the chemical descriptors to the following molecules:

-Strong nucleophile

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

Question 5

From the following anions, pick out the one which is the most stable leaving group.

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

Question 6

For the following reaction, pick out the major product:

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

Question 7

Match the chemical descriptors to the species in the following reaction:

-^-SAc

A) Nucleophile
B) Leaving group
C) Electrophile
D) Counter ion

Question 8

Match the chemical descriptors to the species in the following reaction:

-^-OTs

A) Nucleophile
B) Leaving group
C) Electrophile
D) Counter ion

Question 9

Match the chemical descriptors to the species in the following reaction:

-CH₃OTs

A) Nucleophile
B) Leaving group
C) Electrophile
D) Counter ion

Question 10

Match the chemical descriptors to the species in the following reaction:

-K⁺

A) Nucleophile
B) Leaving group
C) Electrophile
D) Counter ion

Question 11

For a S_N2 reaction, pick out the strongest nucleophile from the following species:

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

Question 12

For the following S_N2 reaction, what would be the relative rate of reaction if the concentrations of the alkyl bromide and potassium acetate (CH₃CO₂K) were tripled?

A) No change in the relative rate
B) The relative rate will increase by three times
C) The relative rate will increase by six times
D) The relative rate will increase by nine times

Question 13

Which of the following factors increase the rate of an S_N1 reaction? Please select all that apply.

A) Concentration of the aliphatic halide
B) Concentration of the nucleophile
C) Temperature
D) Non-polar aprotic solvent
E) Protic solvent
F) Polar aprotic solvent

Question 14

What product(s) would you expect from the following S_N2 reaction?

A) A
B) B
C) C
D) Equimolar mixture of A and B
E) Non-equimolar mixture of A and B

Question 15

From the following bromides, pick out those which can react by a S_N2 mechanism. Please select all that apply.

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

Question 16

Which of the following alkyl halides has the fastest rate for a S_N1 reaction?

A) A
B) B
C) C
D) D
E) All of the above have the same rate of reaction

Question 17

From the following benzylic chlorides, pick out the one which is the poorest electrophile for a S_N1 reaction:

A) A
B) B
C) C

Question 18

For the following reaction, pick out the major product:

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

Question 19

Which of the following alkyl bromides can react with a base in an E2 elimination?

A) A
B) B
C) C
D) D
E) None of these substrates are capable of E2 elimination

Question 20

What is the major product of the following reaction?

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

Question 21

What is the major product of the following reaction?

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

Question 22

For E2 elimination, pick out the descriptor which describes the stereochemical outcome of this elimination step.

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

Question 23

What is the major product of the following E2 elimination?

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

Question 24

From the following reactions, pick out those which do NOT involve carbocation formation. Please select all that apply.

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

Question 25

From the following chlorides, pick out those which are capable of undergoing S_N1 or S_N2 reactions. Please select all that apply.

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

Question 26

Which is the major product of the following reaction?

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

Question 27

Identify the final products and by-products of the following activation reaction. Please select all that apply.

A) H₃C-Cl
B) H₃C-SO₂Cl
C) Cl^-
D) SO₂

Question 28

Which of the following Newman projections depicts the most reactive conformation of ((2S,3R)-3-bromobutan-2-yl)benzene for undergoing E2 elimination?

Redraw instructions from author: The PhMe groups on the four structures below should be Ph (i.e. remove the Me)

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

Question 29

Identify the major elimination product formed under the following conditions:

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

Question 30

For the reaction shown, which one of the following statements is correct.

A) This is an S_N2 reaction which is accelerated in non-polar solvent.
B) This is an S_N2 reaction which is accelerated in polar solvent.
C) This is an S_N1 reaction which is accelerated in non-polar solvent.
D) This is an S_N1 reaction which is accelerated in polar solvent.

Question 31

Identify the possible products formed in the following substitution reaction. Please select all that apply.

A) Product A
B) Product B
C) Product C
D) Product D