Question 1

What is the major organic product obtained from the following reaction? 
A) 
B) 
C) 
D)

Accepted Answer

C

Question 2

Which of the following sets of substituents are all deactivating groups in electrophilic aromatic substitution reactions? A) Cl, CN, NO₂ B) Cl, NH₂, CH₃ C) CH₃, OCH₃, COCH₃ D) CH₃, NH₂, OCH₃

Accepted Answer

All of the substituents in choice A (Cl, CN, and NO₂) are deactivating groups, meaning they decrease the electron density on the aromatic ring and make it less reactive towards electrophiles in electrophilic aromatic substitution reactions. The other choices contain at least one substituent that is not a deactivating group.

Question 3

What is the IUPAC name of the following compound? 
A) 2,4-dibromotoluene
B) 2,4-dibromophenol
C) 2,4-dibromoaniline
D) 4,6-dibromophenol

Accepted Answer

B

Question 4

Which of the following is a correct statement regarding electrophilic aromatic substitution?
A) The carbocation intermediate will lose a proton to regain aromaticity, usually from a position other than the site of electrophilic attack.
B) Formation of the carbocation intermediate has a high activation barrier due to loss of aromaticity.
C) The carbocation intermediate has several resonance structures and is negatively charged.
D) Re-formation of the aromatic ring has a low activation barrier and therefore occurs slowly.
E) Many suitable electrophiles are unreactive and can be stored for long periods of time prior to use.

Accepted Answer

Formation of the carbocation intermediate during electrophilic aromatic substitution involves a high activation barrier because the process temporarily disrupts the aromaticity of the ring, making this step energetically unfavorable.

Question 5

What is the IUPAC name of the following compound? 
A) 3-bromo-4-nitrobenzaldehyde
B) 2-bromo-1-nitro-4-benzoic acid
C) 3-bromo-4-nitroacetophenone
D) 3-bromo-4-nitrobenzoic acid

Accepted Answer

The compound has a benzene ring with a bromine and nitro group in the meta position relative to each other. Therefore, the correct IUPAC name is 3-bromo-4-nitrobenzoic acid. Choice A is incorrect because it is a benzaldehyde, not a carboxylic acid. Choice B is incorrect because the nitro group is in the ortho position, not meta. Choice C is incorrect because it is an acetophenone, not a carboxylic acid.

Question 6

An accurate description of the structure of benzene is:
A) The p bonds are quickly moving around the ring.
B) There are two distinct structures that are in equilibrium.
C) All the carbon-carbon bonds are equal in length.
D) There are distinct single and double bonds.
E) Some bonds are longer than others.

Accepted Answer

Benzene has a ring structure made up of six carbon atoms, and all the carbon-carbon bonds are equal in length. The molecule is often represented as a resonance hybrid with delocalized pi-electrons, rather than as separate single and double bonds. Therefore, options A, B, D, and E are incorrect.

Question 7

Consider the following sequence of reactions:  a)	What is the major organic product obtained from the sequence of reactions?
a. 
 
b.

c.

d.

b)	If KMnO4 had been replaced by Na2Cr2O7, what would be the final product of the reaction?

Accepted Answer

The answer of Consider the following sequence of reactions: ...

Question 8

Draw the major product of the following reaction:

Accepted Answer

The answer of Draw the major product of the following...

Question 9

Which of the following sets of substituents are all o/p-directing in electrophilic aromatic substitution reactions? A) Cl, CH₃, CN B) Br, OH, COCH₃ C) Cl, OH, CH₃ D) CN, NO₂, COCH₃

Accepted Answer

The substituents in choice C, Cl, OH, and CH₃ (which is a thiol group), are all o/p-directing in electrophilic aromatic substitution reactions. This is because they are electron-withdrawing groups that destabilize the aromatic ring, making it more susceptible to attack by electrophiles. The other sets of substituents in choices A, B, and D contain at least one substituent that is meta-directing, meaning it directs electrophiles to the meta-position rather than the ortho or para positions. Therefore, choice C is the best answer.

Question 10

Place the following in order of reactivity towards electrophilic aromatic substitution. 
A) I > II > III > IV
B) I > II > IV > III
C) II > I > III > IV
D) II > I > IV > III
E) III > IV > II > I

Accepted Answer

The answer of Place the following in order of reactivity...

Question 11

Which of the following compounds is aromatic?
A) ethane
B) cyclobuta-1,3-diene
C) benzene
D) cycloocta-1,3,5,7-tetraene

Accepted Answer

Benzene is aromatic because it has a planar ring of 6 carbons with alternating double bonds, meeting the requirements for Hückel's rule (4n+2 pi electrons) and exhibiting extra stability due to delocalization of pi electrons. The other compounds listed do not have this specific arrangement and do not meet the criteria for aromaticity.

Question 12

What is the correct assignment of the names of the following aromatic compounds? 
A) 1 = anisole; 2 = furan; 3 = pyrimidine
B) 1 = aniline; 2 = pyrrole; 3 = pyridine
C) 1 = anisole; 2 = pyridine; 3 = pyrrole
D) 1 = aniline; 2 = imidazole; 3 = pyridine

Accepted Answer

1 is aniline because it has an amino group attached to a benzene ring. 
2 is pyrrole because it has a five-membered ring with one nitrogen atom and four carbon atoms. 
3 is pyridine because it has a six-membered ring with one nitrogen atom and five carbon atoms.

Question 13

Consider the production of 1-bromo-4-nitrobenzene:  a)	Explain why Pathway A for the production of 1-bromo-4-nitrobenzene produces a higher yield of the product.
 	 
b)	If reaction Pathway A is carried out at high temperatures, a trisubstituted product forms. Draw the structure of the product and explain why it forms.

Accepted Answer

The answer of Consider the production of 1-bromo-4-nitrobenzene:  a)	Explain...

Question 14

Which of the following undergoes the most rapid bromination upon treatment with Br₂/FeBr₃? A) benzene B) nitrobenzene C) bromobenzene D) benzaldehyde

Accepted Answer

Benzene undergoes rapid bromination with Br2/FeBr3 because it is the least deactivated by substituents compared to the other options, which have electron-withdrawing groups that slow down the reaction.

Question 15

Which of the following undergoes the most rapid acylation upon treatment with acetyl chloride and AlCl₃? A) benzene B) toluene C) chlorobenzene D) 1,4-dichlorobenzene

Accepted Answer

Toluene undergoes more rapid acylation because it has both a methyl group and an electron-donating benzene ring, which increases its reactivity towards electrophilic substitution reactions. The electron-withdrawing groups present in chlorobenzene and 1,4-dichlorobenzene decrease their reactivity towards electrophilic substitution reactions, while benzene has no substituent to increase its reactivity.

Question 16

Consider the following compound:  a)	Provide the correct IUPAC name for the compound.
 	 
b)	Draw and name the other isomeric nitrotoluenes.

Accepted Answer

The answer of Consider the following compound:  a)	Provide the...

Question 17

Draw the resonance structures for acenaphthene.

Accepted Answer

The answer of Draw the resonance structures for acenaphthene....

Question 18

Draw the structure of 4-bromo-2-fluorotoluene.

Accepted Answer

The answer of Draw the structure of 4-bromo-2-fluorotoluene....

Question 19

Circle the compound(s) in the following set that will undergo both substitution and addition when treated with Br₂.

Accepted Answer

The answer of Circle the compound(s) in the following set...

Question 20

What is the major organic product obtained from the following reaction? 
A) 
B) 
C) 
D)

Accepted Answer

The answer of What is the major organic product obtained...

Quiz 5: Aromatic Compounds

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

Which of the following sets of substituents are all deactivating groups in electrophilic aromatic substitution reactions?

What is the IUPAC name of the following compound?

Which of the following is a correct statement regarding electrophilic aromatic substitution?

What is the IUPAC name of the following compound?

An accurate description of the structure of benzene is:

Consider the following sequence of reactions: a) What is the major organic product obtained from the sequence of reactions? a. b. c. d. b) If KMnO4 had been replaced by Na2Cr2O7, what would be the final product of the reaction?

Draw the major product of the following reaction:

Which of the following sets of substituents are all o/p-directing in electrophilic aromatic substitution reactions?

Place the following in order of reactivity towards electrophilic aromatic substitution.

Which of the following compounds is aromatic?

What is the correct assignment of the names of the following aromatic compounds?

Which of the following undergoes the most rapid bromination upon treatment with Br2/FeBr3?

Which of the following undergoes the most rapid acylation upon treatment with acetyl chloride and AlCl3?

Consider the following compound: a) Provide the correct IUPAC name for the compound. b) Draw and name the other isomeric nitrotoluenes.

Draw the resonance structures for acenaphthene.

Draw the structure of 4-bromo-2-fluorotoluene.

Circle the compound(s) in the following set that will undergo both substitution and addition when treated with Br2.

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

Which of the following undergoes the most rapid bromination upon treatment with Br₂/FeBr₃?

Which of the following undergoes the most rapid acylation upon treatment with acetyl chloride and AlCl₃?

Circle the compound(s) in the following set that will undergo both substitution and addition when treated with Br₂.