Organic Chemistry

Janice G. Smith 3rd edition Chapter 18

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Question 1

Step 1 of electrophilic aromatic substitution involves A) abstraction of an H+ ion from the ring. B) addition of the electrophile to the ring. C) displacement of H+ by the electrophile. D) none of these.

Question 2

Which of the following is NOT an electrophile? A) I B) II C) III D) IV

Question 3

The carbocation intermediate of an electrophilic aromatic substitution reaction A) is resonance stabilized. B) has the positive charge delocalized on 3

carbons. C) loses H+ in an exothermic step. D) all of the above.

Question 4

Halogenation of an aromatic ring A) occurs only at high temperature. B) requires activation of the ring by the

Fe(III) catalyst. C) requires activation of the Br2 by the

Fe(III) catalyst. D) none of the above.

Question 5

Nitric acid, HNO3, produces nitronium ion, +NO2, by A) loss of H2O after protonation by H2SO4. B) by dissociation of OH-. C) by oxidation of dissolved NO2(g) present

in solution. D) none of these.

Question 6

What product would be formed from the reaction of CH3CH2Cl and benzene in the presence of AlCl3? A) I B) II C) III D) IV

Question 7

Rearrangement often accompanies A) Friedel-Crafts alkylation. B) Friedel-Crafts acylation. C) both of these.

Question 8

Friedel-Crafts alkylation of benzene with 1-chloro-2-methylpropane yields A) sec-butylbenzene. B) Isobutylbenzene. C) t-butylbenzene. D) none of these.

Question 9

Which substituted benzene has a substituent that is electron donating by resonance? A) I B) II C) III D) IV

Question 10

Which of the substituted benzenes has a substituent that is activating to electrophilic aromatic substitution? A) I B) II C) III D) IV

Question 11

Which of the following is NOT an ortho-para director? A) -CO2H B) -CH3 C) -OCH3 D) -Cl

Question 12

Which of the following is NOT a meta director? A) -CO2H B) -COCH3 C) -OH D) -NO2

Question 13

Which of the following is ortho-para directing but deactivating? A) -NO2 B) -CH3 C) -Cl D) -CHO

Question 14

What product is expected from the reaction shown? A) I B) II C) III D) Both I and III

Question 15

What is/are the product(s) expected from the reaction shown? A) I B) II C) III D) Both I and III

Question 16

Which of the following substituted benzenes is most activated to electrophilic aromatic substitution? A) I B) II C) III

Question 17

Which of the following substituted benzenes will most readily undergo a Friedel-Crafts alkylation with ethyl chloride and AlCl3? A) I B) II C) III D) IV

Question 18

Which substituted benzene will NOT react with KMnO4? A) I B) II C) III D) IV E) None of these

Question 19

Which reaction sequence is the best for the synthesis of n-propylbenzene starting with benzene? A) Br2/FeBr3; Mg, Et2O; CH3CH2CHO B) Pr-Cl/AlCl3 C) CH3CH2COCl/AlCl3; Zn(Hg) HCl D) All of these

Answer Key Chapter 18 1. B 2. D 3. D 4. B 5. A 6. A 7. A 8. C 9. A 10. D

11. A 12. C 13. C 14. D 15. D 16. C 17. D 18. D 19. C