Chapter 16: The Chemistry of Benzene and its Derivatives

Question 1

Halogenation of Benzene

Answer 1

Question 2

Nitration of Benzene

Answer 2

Question 3

Answer 3

Alkyl group

Question 4

Answer 4

Acyl group

Question 5

Friedel-Crafts Alkylation

Answer 5

Limitations- can be used with methyl and ethyl groups, after that you have to consider carbocation rearrangement. Also ring must not be severly deactivated

Question 6

Friedel Crafts Acylation

Answer 6

Question 7

Clemmenson Reduction

Answer 7

Question 8

Notes on alkylation

Answer 8

• difficult to install just one alkyl group
• each alkyl addition makes the ring more reactive

Question 9

Notes on Acylation

Answer 9

• generally impossible to install >1 acyl group
• presence of acyl group makes ring less reactive

Question 10

Sulfonation

Answer 10

Question 11

Removing sulfa group

Answer 11

Question 12

Hydrogenation of Benzene

Answer 12

-takes a huge amount of energy to hydrogenate first DB, but once aromaticity lost, other 2 bonds hydrogenated almost immediately

Question 13

Activators

Answer 13

• make ring more nucleophilic (donate e- density)
  
  • OH
  • alkyl groups (b/c electron donating

Question 14

Deactivators

Answer 14

• make ring less nucleophilic (withdraw e- density)
  
  • NO2 group

Question 15

Activators are ___ directors

Answer 15

ortho-para

Question 16

Deactivators are ___ directors

Answer 16

meta directors

Exception = halogens (deactivators but O/P directors)

Question 17

How do you decide when there’s more than one director on the ring

Answer 17

• O/P directors always beat meta directors
• Strong activators always beat weak activators

Question 18

Strong Activators

Answer 18

• groups with lone pair next to aromatic ring

Question 19

Moderate Activators

Answer 19

• groups w/ lone pair, but where lone pair is already partially tied up in resonance

Question 20

weak activators

Answer 20

• donate e- density through weak effect called hyperconjugation
  
  • ex-all alkyl groups are weak activators

Question 21

Weak deactivators

Answer 21

• halogen, induction barely beats resonance

Question 22

Moderate deactivators

Answer 22

• withdraw e- density via resonance
• all have pi bond to electronegative atom

Question 23

Strong deactivators

Answer 23

• very powerfully electron withdrawing

Question 24

Steric directing

Answer 24

• bulky groups usually direct para

Question 25

How do you synthesize this?

Answer 25