Deck 8: Alkyl Halides and Elimination Reactions

Question 1

What is the major elimination product in the reaction of 1-bromobutane with potassium tert-butoxide in tert-butanol?

A)cis-2-Butene
B)1-Butene
C)trans-2-Butene
D)Butanol

Answer 1

1-Butene

Question 2

Which of the following is the most reactive substrate in an E2 reaction?

A)I
B)II
C)III
D)IV

Answer 2

IV

Question 3

Which of the following statements about an E1 mechanism is not true?

A)The reaction is fastest with tertiary alkyl halides.
B)A better leaving group makes the reaction rate increase.
C)The reaction follows first-order kinetics.
D)Stronger bases favor the E1 reaction.

Answer 3

Stronger bases favor the E1 reaction.

Question 4

Which of the following is the major elimination product of the following reaction?

A)I
B)II
C)III
D)IV

Question 5

What is the major elimination product obtained from the following reaction?

A)I
B)II
C)III
D)IV

Question 6

What is the major elimination product obtained from the following reaction?

A)I
B)II
C)III
D)IV

Question 7

What is the major product of the following reaction?

A)I
B)II
C)III
D)IV

Question 8

Which of the following is the most reactive substrate in an E1 reaction?

A)I
B)II
C)III
D)IV

Question 9

Which of the following statements about the mechanism of an E2 reaction is true?

A)All bonds are broken and formed in multiple steps.
B)The reaction is not concerted.
C)Entropy favors the reactants of an E2 reaction.
D)Entropy favors the products of an E2 reaction.

Question 10

Which of the following is the major E2 product formed from the following alkyl halide?

A)I
B)II
C)III
D)IV

Question 11

Which of the following statements about an E1 mechanism is true?

A)The identity of the leaving group affects the rate of reaction.
B)The reaction follows second-order kinetics.
C)The reaction is slowest with tertiary substrates.
D)Polar aprotic solvents favor the E1 mechanism.

Question 12

Which of the labeled protons in the compound below is most readily abstracted under E2 conditions?

A)H_a
B)H_b
C)H_c
D)H_d

Question 13

How many different E2 products can form from the dehydrohalogenation of 2-bromobutane?

A)1
B)2
C)3
D)4

Question 14

What is the major elimination product obtained from the following reaction?

A)I
B)II
C)III
D)IV

Question 15

What is the major elimination product obtained from the following reaction?

A)I
B)II
C)III
D)IV

Question 16

Which of the following statements about the mechanism of an E2 reaction is not true?

A)It is fastest with tertiary halides.
B)It exhibits first-order kinetics.
C)A better leaving group should make a faster reaction.
D)All bonds are broken and formed in a single step.

Question 17

Which of the following statements about an E1 mechanism is not true?

A)It is a two-step process and has the same first step as an S_N1 mechanism.
B)It involves the formation of a carbocation from eliminating a good leaving group.
C)A common competing reaction is rearrangement of a less stable carbocation to a more stable carbocation.
D)The loss of a proton by the carbocation is a slow step.

Question 18

Classify each alkene in vitamin D₃ labeled I, II, III by the number of carbon substituents bonded to the double bond.

A)I = Disubstituted; II = trisubstituted; III = trisubstituted.
B)I = Monosubstituted; II = disubstituted; III = trisubstituted.
C)I = Disubstituted; II = disubstituted; III = trisubstituted.
D)I = Disubstituted; II = trisubstituted; III = disubstituted.

Question 19

Which of the following represents the rate law for an E2 reaction?

A)Rate = k[alkyl halide]
B)Rate = k[alkyl halide][base]
C)Rate = k[alkyl halide]²
D)Rate = k[base]²

Question 20

Which of the following is the least reactive substrate in an E2 reaction?

A)I
B)II
C)III
D)IV

Question 21

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

A)Only I
B)Only II
C)Only III
D)I and II

Question 22

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

A)I and II
B)II and III
C)I and III
D)I, II, and III

Question 23

What is the product of the following reaction?

A)Only I
B)Only II
C)Only III
D)II and III

Question 24

What is the most likely mechanism for the reaction below?

A)S_N1
B)S_N2
C)E1
D)E2

Question 25

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

A)Only I
B)Only II
C)Only III
D)II and III

Question 26

Which of the following alkyl halides will afford the product below as the major product in an E2 reaction?

A)I
B)II
C)III
D)IV

Question 27

What is the product of the following reaction?

A)I
B)II
C)III
D)IV

Question 28

Consider the following E2 reaction.What rate equation would be observed for this reaction?

A)Rate = k[CH₃CH₂CH₂Br]
B)Rate = k[CH₃CH₂CH₂Br][KOC(CH₃)₃]
C)Rate = k[CH₃CH₂CH₂Br][KOC(CH₃)₃]²
D)Rate = k[CH₃CH₂CH₂Br]²[KOC(CH₃)₃]

Question 29

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

A)Only I
B)Only II
C)Only III
D)II and III

Question 30

Which of the following is the dihalide that can be used to prepare the alkyne below?

A)I and II
B)II and III
C)I and III
D)I, II, and III

Question 31

Which of the following is most likely to react as a nucleophile rather than a base?

A)I
B)II
C)III
D)IV

Question 32

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

A)Only I
B)Only II
C)Only III
D)II and III

Question 33

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

A)Only I
B)Only II
C)Only III
D)I and II

Question 34

What is the product of the following reaction?

A)I
B)II
C)III
D)IV

Question 35

Which alkyl halide(s) would give the following alkene as the only product in an elimination reaction?

A)Only I
B)Only II
C)Only III
D)I and II

Question 36

What is the product of the following reaction?

A)I
B)II
C)III
D)IV

Question 37

What is the most likely mechanism for the reaction below?

A)S_N1
B)S_N2
C)E1
D)E2

Question 38

Select the elimination product(s) formed by treating the indicated alkyl halide with a base.

A)Only I
B)Only II
C)Only III
D)I, II, and III

Question 39

What is (are) the starting material(s) in the reaction below?

A)Only I
B)Only II
C)Only III
D)II and III

Question 40

Which of the following is the dihalide that can be used to prepare the alkyne below?

A)Only I
B)Only II
C)Only III
D)II and III

Question 41

Which of the following alkenes is the most stable?

A)I
B)II
C)III
D)IV

Question 42

Which of the following alkyl chloride affords alkene A exclusively under E2 reaction condition?

A)I
B)II
C)III
D)IV

Question 43

Which of the following alkyl halide reacts the fastest in an E2 reaction?

A)I
B)II
C)III
D)IV