Deck 11: Nucleophilic Substitution and Elimination Reactions 1: Competition Among Sn2,sn1,e2,and E1 Reactions

Question 1

Which of the following leaving groups will provide the fastest rate of reaction in an S_N1 mechanism?

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

Answer 1

I

Question 2

Which mechanism(s)can occur when the following alkyl halide is treated with CH₃O^?

A)S_N1
B)E1
C)S_N2
D)E2
E)Both S_N2 and E2 are possible.

Answer 2

Both S_N2 and E2 are possible.

Question 3

Which reagent can complete the following reaction?

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

Answer 3

III

Question 4

Which solvent would allow an E2 reaction to occur at the fastest rate?

A)Methanol
B)Acetic acid
C)Ethyl acetate
D)Water
E)Propanol

Question 5

Identify the reagent(s)that will best complete the following reaction.

A)HBr, H₂SO₄
B)Br₂
C)KBr
D)NaBr
E)Both KBr and NaBr will complete the reaction.

Question 6

Which attacking species would favor an E2 reaction over an S_N2 reaction?

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

Question 7

Identify the reagent that best completes the following reaction.

A)NaH
B)NaOH
C)NaNH₂
D)NaOC(CH₃)₃
E)H₃PO₄

Question 8

Which of the following is the best leaving group?

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

Question 9

Which of the following halides would undergo an S_N2 reaction at the fastest rate?

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

Question 10

A secondary alkyl halide can undergo which of the following mechanisms?

A)S_N1
B)E1
C)S_N2
D)E2
E)All of these

Question 11

Which is the best (strongest)nucleophile for an S_N2 reaction?

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

Question 12

Identify the reagent that best completes the following reaction.

A)NaOH
B)LDA
C)NaNH₂
D)H₃PO₄
E)HBr

Question 13

Which reaction mechanism(s)will be favored by a low concentration of Cl^?

A)S_N1
B)S_N2
C)E1
D)E2
E)A mixture of E1 and S_N1

Question 14

Which of the following bases would make an E2 reaction occur at the fastest rate?

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

Question 15

What reagent(s)can complete the following reaction?

A)I
B)II
C)III
D)IV
E)All of these reagents can complete the reaction.

Question 16

Which is the best (strongest)nucleophile for an S_N2 reaction?

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

Question 17

Which reaction mechanism(s)will be favored by a high concentration of Br ^?

A)S_N1
B)S_N2
C)E1
D)E2
E)A mixture of E1 and S_N1

Question 18

Which attacking species would favor an E2 reaction over an S_N2 reaction?

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

Question 19

Which solvent would be best for an S_N1 reaction?

A)Acetone
B)DMSO
C)Hexane
D)Ethanol
E)Ethyl acetate

Question 20

Which of the following bases would make an E2 reaction occur at the fastest rate?

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

Question 21

Which mechanism(s)would be favored under the following reaction conditions?

A)S_N1
B)S_N2
C)E1
D)E2
E)A mixture of S_N1 and E1

Question 22

Which reaction mechanism(s)would be favored by the following conditions?

Question 23

Supply a base that would favor the following elimination product over a substitution product.

Question 24

Show how the following alkyne can be synthesized from an acetylide ion and an alkyl halide.

Question 25

Using the two reactants shown below,draw the mechanisms and products for reactions based on four different mechanisms: S_N1,E1,S_N2,and E2.

Question 26

Supply a base that would favor the following elimination product over a substitution product.

Question 27

Show the most likely product of the following reaction.

Question 28

What reagent(s)can be used to successfully complete the following reaction?

Question 29

Show the starting material needed to complete the following reaction.

Question 30

Rank the following attacking species in order of slowest reacting to fastest reacting in an E2 reaction.

Question 31

Rank the following attacking species in order of slowest reacting to fastest reacting in an E2 reaction.

Question 32

Name two bases that are strong enough to deprotonate the following alkyne.

Question 33

Rank the following nucleophiles in order of weakest to strongest.

Question 34

Give the product and mechanism for the following reaction.Be sure to include all mechanism arrows,lone pairs of electrons,and formal charges in your mechanism.

Question 35

Identify the major product(s)of the following reaction.

A)I
B)II
C)III
D)IV
E)A mixture of I and II

Question 36

What is the major product of the following reaction?

A)I
B)II
C)III
D)IV
E)None of these will be produced.

Question 37

Rank the following nucleophiles in order of weakest to strongest.

Question 38

Rank the following leaving groups' ability to leave in an S_N1 reaction from worst leaving group to best leaving group.

Question 39

What is the major product of the following reaction?

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

Question 40

Which mechanism(s)would be favored under the following reaction conditions?

A)S_N1
B)S_N2
C)E1
D)E2
E)A mixture of S_N1 and E1

Question 41

For the following set of reaction conditions,use the table below to identify which mechanism is favored by each factor,and determine which mechanism is favored overall.

Question 42

Give the product and the mechanism for the following intramolecular reaction.Be sure to include all mechanism arrows,lone pairs,and formal charges.

Question 43

Give the product and mechanism for the following reaction.Be sure to include all mechanism arrows,lone pairs of electrons,and formal charges in your mechanism.

Question 44

For the following set of reaction conditions,use the table below to identify which mechanism is favored by each factor,and determine which mechanism is favored overall.Also supply the expected product.

Question 45

Circle the solvent(s)that would speed up an E1 reaction mechanism.

Question 46

Rank the following leaving groups' ability to leave in an E1 reaction from worst leaving group to best leaving group.

Question 47

Supply the product of the following reaction,and name the mechanism responsible for its creation.

Question 48

For the following set of reaction conditions,use the table below to identify which mechanism is favored by each factor,and determine which mechanism is favored overall.Also supply the expected product.

Question 49

List all the reaction mechanisms that are possible with a tertiary alkyl halide.Choose from S_N1, E1_,S_N2, and E2 mechanisms.

Question 50

For the following set of reaction conditions,use the table below to identify which mechanism is favored by each factor,and determine which mechanism is favored overall.Also supply the major product.