Deck 10: Synthesis Using Aromatic Materials: Electrophilic Aromatic Substitution and Directed Ortho Metalation

Question 1

Why is nitrobenzene NOT compatible with Friedel-Crafts alkylation?

A)because the nitro group is too electron withdrawing to undergo Friedel-Crafts alkylation
B)because the nitrogen acts as a Lewis base and reacts with AlCl₃ instead
C)because the nitro group is too electron donating to undergo Friedel-Crafts alkylation
D)because the nitrogen group acts as a Lewis acid and reacts with AlCl₃ instead

Answer 1

because the nitro group is too electron withdrawing to undergo Friedel-Crafts alkylation

Question 2

What set of reagents would most effectively produce ethylbenzene from benzene shown below?

A)AlCl₃,EtCl
B)1)AlCl₃, 2)Zn/HCl
C)1)MgBrEt,ether 2)H₃O⁺
D)1)EtBr

Answer 2

1)AlCl₃, 2)Zn/HCl

Question 3

What is the role of FeBr₃ in the following reaction?

A)It activates bromine and makes it more nucleophilic.
B)It activates bromine and makes it more electrophilic.
C)It activates toluene and makes it more nucleophilic.
D)It activates toluene and makes it more electrophilic.

Answer 3

It activates bromine and makes it more electrophilic.

Question 4

As substituents on aromatic rings,which of the following best describes halides?

A)meta directing and activating
B)meta directing and deactivating
C)ortho/para directing and activating
D)ortho/para directing and deactivating

Question 5

Which of the following would be the product of the reaction shown below?

A)
B)
C)
D)

Question 6

What is the role of sulfuric acid in the following reaction scheme?

A)to protonate the aromatic ring and make it a better electrophile
B)to form dipole interactions with the developing positive charge in the aromatic ring
C)to protonate nitric acid to form the nitronium ion
D)to regenerate nitric acid

Question 7

Which of the following would be the product of the reaction shown below?

A)
B)
C)
D)No reaction would occur.

Question 8

What route would work best for the synthesis of the following aromatic molecule from benzene shown below?

A)1)AlCl₃, 2)HNO₃,H₂SO₄
B)1)HNO₃,H₂SO₄ 2)AlCl₃,
C)1)HNO₃,
D)This product cannot be formed since Friedel-Crafts reactions are incompatible with nitrobenzene.

Question 9

What would be the expected product of the following reaction?

A)
B)
C)
D)No product would form.

Question 10

Why is aniline NOT compatible with Friedel-Crafts alkylation?

A)because the amino group is too electron withdrawing to undergo Friedel-Crafts alkylation
B)because the nitrogen acts as a Lewis base and reacts with AlCl₃ instead
C)because the amino group is too electron donating to undergo Friedel-Crafts alkylation
D)because the nitrogen group acts as a Lewis acid and reacts with AlCl₃ instead

Question 11

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

A)
B)
C)
D)

Question 12

What sequence of reagents would best achieve the transformation shown below?

A)1)Br₂,FeBr₃ 2)HNO₃,H₂SO₄ 3)Fe,HCL
B)1)Br₂,FeBr₃ 2)Fe,HCL 3)HNO₃,H₂SO₄
C)1)HNO₃,H₂SO₄ 2)Br₂,FeBr₃ 3)Fe,HCL
D)1)HNO₃,H₂SO₄ 2)Fe,HCL 3)Br₂,FeBr₃

Question 13

Which of the following best describes the substituent on the molecule shown below?

A)It is ortho/para directing by electron-delocalization.
B)It is meta directing by electron-delocalization.
C)It is ortho/para directing by induction.
D)It is meta directing by induction.

Question 14

Which of the following statements best describes the set of aromatic molecules show below?

A)A is the most activated and B is the least activated towards S_EAr reactions.
B)C is the most activated and B is the least activated towards S_EAr reactions.
C)A is the most activated and C is the least activated towards S_EAr reactions.
D)B is the most activated and A is the least activated towards S_EAr reactions.

Question 15

Which of the following best describes the carboxylic acid substituent in benzoic acid shown below?

A)It is ortho/para directing and electron donating by electron-delocalization.
B)It is meta directing and electron withdrawing by electron-delocalization.
C)It is ortho/para directing and electron donating by electron-delocalization..
D)It is meta directing and electron withdrawing by electron-delocalization..

Question 16

Which of the following best describes the substituent on the molecule shown below?

A)It is ortho/para directing and electron donating by electron-delocalization.
B)It is meta directing and electron withdrawing by electron-delocalization.
C)It is ortho/para directing and electron donating by electron-delocalization..
D)It is meta directing and electron withdrawing by electron-delocalization..

Question 17

Which of the following compounds will the reaction below lead to?

A)
B)
C)
D)

Question 18

Compared to benzene,what best describes the reactivity of nitrobenzene (shown below)to S_EAr reactions?

A)It is more reactive than benzene.
B)It is less reactive than benzene.
C)It is similarly reactive as benzene.
D)There is not enough information to determine reactivity.

Question 19

Which of the following best describes the two molecules shown below?

A)A is more reactive to S_EAr than B and is meta directing.
B)A is less reactive to S_EAr than B and is meta directing.
C)A is more reactive to S_EAr than B and is para/ortho directing.
D)A is less reactive to S_EAr than B and is para/ortho directing.

Question 20

Which of the following statements best describes the set of aromatic molecules,show below?

A)A is the most activated and B is the least activated towards S_EAr reactions.
B)C is the most activated and B is the least activated towards S_EAr reactions.
C)A is the most activated and C is the least activated towards S_EAr reactions.
D)B is the most activated and C is the least activated towards S_EAr reactions.

Question 21

Which of the following aromatic molecules would NOT be suitable for directed ortho metalation?

A)
B)
C)
D)

Question 22

In an S_EAr reaction,how would you describe an alkyl group on an aromatic ring?

A)strongly deactivating
B)weakly deactivating
C)weakly activating
D)strongly activating

Question 23

Which of the following compounds will the reaction below lead to?

A)
B)
C)
D)

Question 24

Which of the following molecules would be required as a reacting to form the product in the reaction scheme shown below?

A)
B)
C)
D)The transformation shown above is not possible.

Question 25

Which of the following best describes FeBr₃ in the reaction shown below?

A)Lewis acid
B)Lewis base
C)solvent
D)nucleophile

Question 26

Which of the following best describes the role of aluminum chloride in a Friedel-Crafts reaction?

A)It is a Lewis base and is used to activate the alkyl halide.
B)It is a Lewis acid and is used to activate the alkyl halide.
C)It is a Lewis base and is used to activate the aromatic ring.
D)It is a Lewis acid and is used to activate the aromatic ring.

Question 27

Predict the product of the following reaction shown below.

A)
B)
C)
D)

Question 28

Which of the following compounds will the reaction below lead to?

A)
B)
C)
D)

Question 29

Which of the following best describes an activating group in an S_EAr reaction?

A)electron rich with a smaller ÄG of reaction relative to benzene
B)electron poor with a smaller ÄG of reaction relative to benzene
C)electron rich with a larger ÄG of reaction relative to benzene
D)electron poor with a larger ÄG of reaction relative to benzene

Question 30

What is the IUPAC name for m-xylene?

A)1,2-dimethylbenzene
B)1,3-dimethylbenzene
C)2-methylphenol
D)3-methylphenol

Question 31

Which of the following compounds will the reaction below lead to?

A)
B)
C)
D)

Question 32

Which of the following compounds will the reaction below lead to?

A)
B)
C)
D)

Question 33

What is the common name for methoxybenzene?

A)analine
B)anisole
C)phenol
D)toluene

Question 34

Which of the following statements best describes the reaction shown below?

A)Benzene is the nucleophile;HNO₃ is the electrophile.
B)Benzene is the electrophile;HNO₃ is the nucleophile.
C)Benzene is the nucleophile;NO₂ is the electrophile.
D)Benzene is the electrophile;NO₂ is the nucleophile.

Question 35

Which of the following molecules would be required as a reacting to form the product in the reaction scheme shown below?

A)
B)
C)
D)The transformation shown above is not possible.

Question 36

Which molecule will react faster with Br₂ in the presence of iron bromide and why?

A)A because the amino group makes the ring more negative through charge delocalization
B)B because the nitro group makes the ring more negative through charge delocalization
C)A because the amino group makes the ring less negative through charge delocalization
D)B because the nitro group makes the ring less negative through charge delocalization

Question 37

In an S_EAr reaction,how would you describe a halogen group on an aromatic ring?

A)ortho/para directing and deactivating
B)ortho/para directing and activating
C)meta directing and deactivating
D)meta directing and activating

Question 38

Which of the following best describes a deactivating group in an S_EAr reaction?

A)electron rich with a smaller ÄG of reaction relative to benzene
B)electron poor with a smaller ÄG of reaction relative to benzene
C)electron rich with a larger ÄG of reaction relative to benzene
D)electron poor with a larger ÄG of reaction relative to benzene

Question 39

Which of the following compounds will the reaction below lead to?

A)
B)
C)
D)

Question 40

In an S_EAr reaction,how would you describe an amino group on an aromatic ring?

A)strongly deactivating
B)weakly deactivating
C)weakly activating
D)strongly activating

Question 41

Carbocation rearrangements can involve either the movements of hydrides or alkyl groups.

Question 42

In a Friedel-Crafts reaction,aluminum chloride acts as a Lewis acid.

Question 43

Aromatic ð bonds are more nucleophilic then non-aromatic ð bonds.

Question 44

Electron donating groups stabilize the arenium ion during S_EAr reactions.

Question 45

Sulfate groups are meta directing substituents in S_EAr reactions.

Question 46

Alkyl groups are meta directing substituents in S_EAr reactions.

Question 47

Amino groups are ortho/para directing substituents in S_EAr reactions.

Question 48

What is the expected product of the reaction shown below?

A)
B)
C)
D)A mixture of

Question 49

Alcohol groups are activating substituents in S_EAr reactions.

Question 50

Nitro groups are activating substituents in S_EAr reactions.

Question 51

During an electrophilic aromatic substitution reaction,the aromatic ring becomes positively charged.

Question 52

Sterics plays a role in whether a group adds ortho or para on an aromatic ring.

Question 53

What is the driving force for the last step in an S_EAr mechanism?

A)stabilization of charge
B)loss of an acidic proton
C)gain of a double bond
D)restoration of aromaticity

Question 54

Meta directing groups tend to be deactivating groups in S_EAr reactions.

Question 55

The role of FeBr₃ in the bromination of benzene is to make bromine more nucleophilic.

Question 56

Friedel-Crafts acylation reactions run the risk of carbocation rearrangements.

Question 57

A secondary carbocation will undergo rearrangement to become a primary carbocation.

Question 58

What is the expected product of the reaction shown below?

A)
B)
C)
D)A mixture of

Question 59

The aromatic ð electrons act as the nucleophile in S_EAr reactions.

Question 60

Which of the following compounds will the reaction below lead to?

A)
B)
C)
D)

Question 61

In an electrophilic aromatic substitution reaction,the aromatic group acts as a(n)_______________.

Question 62

Design a reaction pathway to generate the following aromatic molecule from benzene.Show each intermediate.

Question 63

Nitro groups on aromatic rings act as _______________ directors in S_EAr reactions.

Question 64

Acyl groups are meta directing substituents in S_EAr reactions.

Question 65

Fluorination of an aromatic ring through a S_EAr mechanism requires no catalyst.

Question 66

An alternative to electrophilic aromatic substitution reactions are DOM reactions,which stands for _______________.

Question 67

Sulfate groups are considered para/ortho directors in S_EAr reactions.

Question 68

_______________ is a Lewis acid required for Friedel-Crafts reactions

Question 69

Acylation of an amine to an amide increases its activation potential in S_EAr reactions.

Question 70

Nitro groups are strongly _______________ substituents in S_EAr reactions.

Question 71

Electron-donating substituents on aromatic rings act as _______________ directors in S_EAr reactions.

Question 72

Friedel-Crafts alkylations cannot be performed in the presence of a(n)________ or a(n)_______ group.

Question 73

Protonation of an amino group plays no role in its directing influence in S_EAr reactions.

Question 74

SO₃ is the nucleophile in the sulfation of aromatic rings.

Question 75

Sulfate groups are considered deactivating groups in S_EAr reactions.

Question 76

Iron filings in the presence of hydrochloric acid can reduce an aromatic ketone into an alkyl group.

Question 77

The common name for aminobenzene is _______________ .

Question 78

The IUPAC name for anisole is _______________ .

Question 79

Friedel-Crafts acylation often results in a(n)_______________ functional group.

Question 80

Iron filings in the presence of hydrochloric acid can reduce a nitro group into an amino group.