Phenol

Question 1

Phenol reactivity

Answer 1

1. lone pair of electrons on oxygen
2. partially delocalised into ring
3. weakens OH bond
4. phenol donates H+
5. stabilises C6H5O-
6. increased electron density
7. induces dipoles

Question 2

Phenol to sodium phenoxide

Answer 2

Reagents: NaOH / Na
Side products: H2O / H2

Question 3

Phenol to 2-nitrophenol or 4-nitrophenol

Answer 3

Reagents: dilute HNO3
Mechanism: electrophilic substitution/ nitration

Question 4

Phenol to 2,4,6-nitrophenol

Answer 4

Reagents: c.HNO3
Mechanism: electrophilic substitution/ nitration

Question 5

Phenol to 2,4,6 tribromophenol

Answer 5

Reagents: 3Br2
Side products: 3HBr
Observations: decolourises, produces white solid
Mechanism: electrophilic substitution/ bromination

Question 6

Electron releasing

Answer 6

1. increased ring electron density
2. increased electrophile attraction
3. rate of reaction increases
4. 2,4 directing

Question 7

Electron withdrawing

Answer 7

1. decreased ring electron density
2. decreased electrophile attraction
3. rate of reaction decreases
4. 3,5 directing

Question 8

Electron releasing side chains

Answer 8

CH3
C2H5
OH
NH2

Question 9

Electron withdrawing side chains

Answer 9

NO2
C=O
COOH

Question 10

Phenol properties

Answer 10

1. weak acid
2. react with NaOH/Na
3. doesn’t react with carbonates