Chapter 16 Full Test Bank Reactions Of Aromatic Compounds

Organic Chemistry, 6e (Smith)

Chapter 16 Reactions of Aromatic Compounds

1) What is the first step in the general mechanism for electrophilic aromatic substitution?

A) Protonation of the aromatic ring

B) Deprotonation of the aromatic ring

C) Addition of the electrophile to the aromatic ring

D) Loss of the electrophile from the aromatic ring

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

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

3) What is the electrophile in aromatic nitration?

A) NO+

B) NO2+

C) NO3+

D) NO2H

4) What is the electrophile in aromatic sulfonation?

A) H2SO3

B) H2SO4

C) SO3+

D) HSO3+

5) Why is sulfuric acid used in aromatic nitration?

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

6) What is the electrophile in the Friedel-Crafts alkylation reaction with tert-butylchloride?

A) The tert-butyl cation

B) A complex of tert-butylchloride and aluminum chloride

C) A proton

D) Aluminum chloride

7) Which of the following halides will not work as an electrophile in a Friedel-Crafts alkylation reaction?

A) I

B) II

C) III

D) IV

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

A) Steric and electronic

B) Inductive and steric

C) Inductive and resonance

D) Resonance and electronic

9) Why is the nitro group a meta director?

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

10) What is a major problem with Friedel-Crafts alkylation?

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.

11) Which of the following statements about the mechanism of electrophilic aromatic substitution is not true?

A) All electrophilic aromatic substitution reactions occur via a two-step mechanism.

B) The transition state of the first step is lower in energy.

C) The first step is the rate-determining step.

D) The second step is the fast step.

12) What will be the site that leads to the major mono substitution product for an electrophilic aromatic substitution reaction of the following compound?

A) I

B) II

C) III

D) IV

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

A) I

B) II

C) III

D) IV

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

A) I

B) II

C) III

D) IV

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

A) I

B) II

C) III

D) IV

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

A) I

B) II

C) III

D) IV

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

A) I

B) II

C) III

D) IV

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

A) I

B) II

C) III

D) IV

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

A) I

B) II

C) III

D) IV

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

A) I

B) II

C) III

D) IV

21) Which of the following substituents are activators in electrophilic aromatic substitution?

A) CH3O ¾

B) Cl ¾

C) NO2 ¾

D) HSO3¾

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

A) HO ¾

B) CH3NH ¾

C) CH3O ¾

D) (CH3)3N+¾

23) Which of the following substituents is an ortho, para director?

A) ¾ CHO

B) ¾ COOH

C) ¾ NHCOR

D) ¾ CN

24) Which of the following substituents is a meta director?

A) ¾ N(CH3)2

B) ¾ OCH3

C) ¾ NHCOCH3

D) ¾ SO3H

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

A) Only I

B) Only II

C) Only III

D) Only I and III

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

A) Only I

B) Only II

C) Only III

D) Only I and II

27) Rank the following compounds in order of increasing reactivity in electrophilic aromatic substitution.

A) I < II < III < IV

B) II < I < IV < III

C) III < IV < I < II

D) II < I < III < IV

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

A) II > IV > I > III

B) II > III > IV > I

C) IV > II > I > III

D) IV > I > II > III

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

A) IV > II > III > I

B) II > III > IV > I

C) III > IV > II > I

D) II > IV > III > I

30) Rank the following deactivating groups in order of increasing deactivating strength, listing the least deactivating first.

A) I < II < III < IV

B) II < III < IV < I

C) II < I < III < IV

D) IV < III < I < II

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

A) Only I

B) Only II

C) Only I and II

D) Only III

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

A) Only I and II

B) Only I and III

C) Only II and III

D) Only IV

33) How can polyalkylation be minimized in Friedel-Crafts alkylation?

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.

34) What is the major product of the following reaction?

A) I

B) II

C) III

D) IV

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

A) Only I

B) Only II

C) Only III

D) Only I and II

36) What are the two distinct pathways for nucleophilic aromatic substitution?

A) Addition-substitution and substitution-addition

B) Addition-elimination and elimination-addition

C) Addition-addition and elimination-elimination

D) Elimination-substitution and substitution-elimination

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

A) Carbocation

B) Radical

C) Benzyne

D) Carbanion

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

A) Carbocation

B) Radical

C) Benzyne

D) Carbanion

39) Which of the following statements about nucleophilic aromatic substitution is not true?

A) Increasing the electronegativity of the halogen increases the reactivity of the aryl halide.

B) Increasing the number of electron-withdrawing groups increases the reactivity of the aryl halide.

C) Electron-withdrawing groups stabilize the intermediate carbanion, and lower the energy of the transition state.

D) When a nitro group is located meta to the halogen, the negative charge of the intermediate carbanion can be delocalized onto the NO2 group, thus stabilizing it.

40) Which of the following statements about nucleophilic aromatic substitution is true?

A) For the addition-elimination pathway, the nucleophile may become attached either at the site bearing the leaving group or at the site bearing the ortho hydrogen atom.

B) For the elimination-addition pathway, the nucleophile becomes attached only at the site bearing the leaving group.

C) The elimination-addition mechanism is not as common as the addition-elimination mechanism.

D) In the addition-elimination mechanism, the aromatic ring first accepts a pair of electrons from a nucleophile to form a cationic intermediate.

41) Rank the following compounds in order of increasing reactivity in nucleophilic aromatic substitution.

A) III < II < I

B) I < II < III

C) III < I < II

D) I < III < II

42) What is the major product of the following reaction?

A) I

B) II

C) III

D) IV

43) Which aryl fluoride reacts the fastest with NaOH?

A) I

B) II

C) III

D) IV

44) In addition to the product shown, what other product is formed in the following reaction?

A) I

B) II

C) III

D) IV

45) Which set of reagents would most likely bring about the following transformation?

A) Br2 and FeBr3

B) NBS and light

C) Br2 in CCl4

D) NaBr and H2O

46) What is the product of the following sequence of reactions?

A) I

B) II

C) III

D) IV

47) What is the product of the following reaction?

A) I

B) II

C) III

D) IV

48) What is the product of the following reaction?

A) I

B) II

C) III

D) None of these

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

A) [1] LiAlH4; [2] H2O

B) Zn (Hg), HCl

C) NH3, NaOH

D) H2, Pd-C

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

A) [1] LiAlH4; [2]H2O

B) Zn (Hg), HCl

C) NH3, NaOH

D) H2, Pd-C

51) What is the product of the following reaction?

A) I

B) II

C) III

D) IV

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

A) I

B) II

C) III

D) IV

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

A) I

B) II

C) III

D) IV

54) 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? 

A) I

B) II

C) III

D) IV

55) What is the structure of compound A? 

A) I

B) II

C) III

D) IV

56) What is the product of the following monobromonation reaction?

A) Only I

B) Only II

C) Only III

D) Only I and III

57) What is the major organic product of the following reaction?

A) I

B) II

C) III

D) IV

58) What is the major organic product of the following reaction?

A) I

B) II

C) III

D) IV

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

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

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

A) CH3CH2C(O)Cl, AlCl3 2. HNO3, H2SO4 3. Zn(Hg), HCl

B) HNO3, H2SO4 2. CH3CH2C(O)Cl, AlCl3 3. Zn(Hg), HCl

C) CH3CH2C(O)Cl, AlCl3 2. Zn(Hg), HCl 3. HNO3, H2SO4

D) Zn(Hg), HCl 2. CH3CH2C(O)Cl, AlCl3 3. HNO3, H2SO4