Question 1

What is the major product of electrophilic addition of HBr to the following alkene?

Accepted Answer

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

Question 2

How can polyalkylation be minimized in Friedel-Crafts alkylation?

Accepted Answer

A) Use a large excess of alkyl halide relative to the aromatic compound. 
B) Use a large excess of benzene relative to the alkyl halide. 
C) Use an alkyl halide without a Lewis acid catalyst. 
D) Use a large excess of the Lewis acid catalyst. 
A) Use a large excess of alkyl halide relative to the aromatic compound. 
B) Use a large excess of benzene relative to the alkyl halide. 
C) Use an alkyl halide without a Lewis acid catalyst. 
D) Use a large excess of the Lewis acid catalyst. B

Question 3

Rank the following activating groups in order of decreasing strength of activation,listing the most activating first.

Accepted Answer

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

Question 4

What is the driving force for losing a proton as the last step in electrophilic aromatic substitution?

Accepted Answer

A) To neutralize the base that is present 
B) To make room for the electrophile 
C) To make the ring more reactive 
D) To rearomatize the ring system 
A) To neutralize the base that is present 
B) To make room for the electrophile 
C) To make the ring more reactive 
D) To rearomatize the ring system

Question 5

What is a major problem with Friedel-Crafts alkylation?

Accepted Answer

A) It requires high temperatures. 
B) The conditions are too acidic. 
C) The starting material is frequently over-alkylated. 
D) The products coordinate with the aluminum chloride. 
A) It requires high temperatures. 
B) The conditions are too acidic. 
C) The starting material is frequently over-alkylated. 
D) The products coordinate with the aluminum chloride.

Question 6

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

Accepted Answer

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

Question 7

What is the best choice of reagent to bring about the following transformation?

Accepted Answer

A) [1] LiAlH4; [2]H2O 
B) Zn (Hg),HCl 
C) NH3,NaOH 
D) H2,Pd-C 
A) [1] LiAlH4; [2]H2O 
B) Zn (Hg),HCl 
C) NH3,NaOH 
D) H2,Pd-C

Question 8

What reagents would be necessary to produce the following product from benzene?

Accepted Answer

A) CH3Cl,AlCl3 2.HNO3,H2SO4 3.KMnO4 
B) HNO3,H2SO4 2.CH3Cl,AlCl3 3.KMnO4 
C) KMnO4 2.CH3Cl,AlCl3 3.HNO3,H2SO4 
D) KMnO4 2.HNO3,H2SO4 3.CH3Cl,AlCl3 
A) CH3Cl,AlCl3 2.HNO3,H2SO4 3.KMnO4 
B) HNO3,H2SO4 2.CH3Cl,AlCl3 3.KMnO4 
C) KMnO4 2.CH3Cl,AlCl3 3.HNO3,H2SO4 
D) KMnO4 2.HNO3,H2SO4 3.CH3Cl,AlCl3

Question 9

Which of the following substituents are deactivators in electrophilic aromatic substitution?

Accepted Answer

A) HO ¾ 
B) CH3NH ¾ 
C) CH3O ¾ 
D) (CH3)3N+¾ 
A) HO ¾ 
B) CH3NH ¾ 
C) CH3O ¾ 
D) (CH3)3N+¾

Question 10

What are the two effects that have to be considered to determine the influence a substituent will have on electrophilic aromatic substitution?

Accepted Answer

A) Steric and electronic 
B) Inductive and steric 
C) Inductive and resonance 
D) Resonance and electronic 
A) Steric and electronic 
B) Inductive and steric 
C) Inductive and resonance 
D) Resonance and electronic

Question 11

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

Accepted Answer

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

Question 12

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

Accepted Answer

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

Question 13

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

Accepted Answer

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

Question 14

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

Accepted Answer

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

Question 15

Why is the nitro group a meta director?

Accepted Answer

A) Because it is sterically very large 
B) Because it adds electron density to the meta position,thus activating it 
C) Because it stabilizes the intermediate cation 
D) Because it removes more electron density from the ortho and para positions than the meta position,thus deactivating the meta position less 
A) Because it is sterically very large 
B) Because it adds electron density to the meta position,thus activating it 
C) Because it stabilizes the intermediate cation 
D) Because it removes more electron density from the ortho and para positions than the meta position,thus deactivating the meta position less

Question 16

Rank the following compounds in order of decreasing reactivity in electrophilic aromatic substitution.

Accepted Answer

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

Question 17

Why is sulfuric acid used in aromatic nitration?

Accepted Answer

A) To keep the reaction from getting too basic 
B) To form the active electrophile NO2+ 
C) To protonate the aromatic ring 
D) To keep the reaction from getting too acidic 
A) To keep the reaction from getting too basic 
B) To form the active electrophile NO2+ 
C) To protonate the aromatic ring 
D) To keep the reaction from getting too acidic

Question 18

Which aryl fluoride reacts the fastest with NaOH?

Accepted Answer

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

Question 19

Consider the tetracyclic aromatic compound drawn below,with rings labelled as I,II,III,and IV.Which of the four rings is least reactive in electrophilic aromatic substitution?

Accepted Answer

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

Question 20

What is the reactive intermediate formed in the elimination-addition mechanism of nucleophilic aromatic substitution?

Accepted Answer

A) Carbocation 
B) Radical 
C) Benzyne 
D) Carbanion 
A) Carbocation 
B) Radical 
C) Benzyne 
D) Carbanion

Exam 16: Reactions of Aromatic Compounds

What is the major product of electrophilic addition of HBr to the following alkene?

How can polyalkylation be minimized in Friedel-Crafts alkylation?

Rank the following activating groups in order of decreasing strength of activation,listing the most activating first.

What is the driving force for losing a proton as the last step in electrophilic aromatic substitution?

What is a major problem with Friedel-Crafts alkylation?

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

What is the best choice of reagent to bring about the following transformation?

What reagents would be necessary to produce the following product from benzene?

Which of the following substituents are deactivators in electrophilic aromatic substitution?

What are the two effects that have to be considered to determine the influence a substituent will have on electrophilic aromatic substitution?

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

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

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

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

Why is the nitro group a meta director?

Rank the following compounds in order of decreasing reactivity in electrophilic aromatic substitution.

Why is sulfuric acid used in aromatic nitration?

Which aryl fluoride reacts the fastest with NaOH?

Consider the tetracyclic aromatic compound drawn below,with rings labelled as I,II,III,and IV.Which of the four rings is least reactive in electrophilic aromatic substitution?

What is the reactive intermediate formed in the elimination-addition mechanism of nucleophilic aromatic substitution?

Structure and Bonding

Acids and Bases

Introduction to Organic Molecules and Functional Groups

Alkanes

Stereochemistry

Understanding Organic Reactions

Alkyl Halides and Nucleophilic Substitution

Alkyl Halides and Elimination Reactions

Alcohols,ethers,and Related Compounds

Alkenes and Addition Reactions

Alkynes and Synthesis

Oxidation and Reduction

Radical Reactions

Conjugation,resonance,and Dienes

Benzene and Aromatic Compounds

Introduction to Carbonyl Chemistry; Organometallic Reagents; Oxidation and Reduction

Aldehydes and Ketones - Nucleophilic Addition

Carboxylic Acids and the Acidity of the O-H Bond

Carboxylic Acids and Their Derivatives Nucleophilic Acyl Substitution

Substitution Reactions of Carbonyl Compounds at the a Carbon

Carbonyl Condensation Reactions

Amines

Carbon-Carbon Bond-Forming Reactions in Organic Synthesis

Pericyclic Reactions

Carbohydrates

Amino Acids and Proteins

Synthetic Polymers

Lipids

Spectroscopy A: Mass Spectrometry

Spectroscopy B: Infrared Spectroscopy

Spectroscopy C: Nuclear Magnetic Resonance Spectroscopy

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