Ch.17 - Reactions of Aromatic Compounds

Question 1

What is the catalyst in a bromination of benzene?

Answer 1

FeBr3

Question 2

What is a sigma complex?

Answer 2

the resonance-stabilized carbocation made when a pi electron from benzene attacks a strong electrophile

Question 3

How is aromaticity regained in Electrophilic Aromatic Substitution (EAS)?

Answer 3

by the loss of a proton

Question 4

Is bromination an endothermic or exothermic reaction?

Answer 4

exothermic

Question 5

What catalyst is most often used in the chlorination of benzene?

Answer 5

AlCl3

Question 6

What does iodination require to produce an iodide cation?

Answer 6

an acidic oxidizing agent (like HNO3)

Question 7

What is the catalyst of the nitration of benzene?

Answer 7

H2SO4

Question 8

What treatment will reduce a nitro group (NO2) to an amino group (NH2)?

Answer 8

zinc, tin, or iron in dilute acid (aq HCl)

Question 9

What is the catalyst in the sulfonation of benzene?

Answer 9

H2SO4

Question 10

What is the electrophile in the sulfonation of benzene reaction?

Answer 10

SO3

Question 11

what is the -SO3H group called?

Answer 11

sulfonic acid

Question 12

Sulfur trioxide is a ______ electrophile.

Answer 12

strong

Question 13

What does the bonding look like in sulfur trioxide?

Answer 13

3 sulfonyl bonds drawing electron density away from the S atom

Question 14

Is sulfonation reversible?

Answer 14

yes

Question 15

How can the sulfonic acid group be removed from an aromatic ring?

Answer 15

H+ and heat

Question 16

Toluene reacts 25 times _____ than benzene.

Answer 16

faster

Question 17

what group is an activator of the nitration of toluene?

Answer 17

methyl group

Question 18

The product mix or the nitration of toluene mostly contains what?

Answer 18

ortho- and para-

Question 19

Why are ortho and para attacks preferred?

Answer 19

their resonance structures include one tertiary carbocation