17 Hydroxy compounds

Question 1

State and explain the relative acidities of ethanol and phenol. Ref: 9701/42/F/M/16

Answer 1

Phenol is more acidic than ethanol because the OH bond is weakened as the lone pair of the OH is delocalized over the benzene ring.

Question 2

(ii) In the table below, give the reaction conditions for the formation of organic products D and E and draw their structures.

Answer 2

7 (ii)

Question 3

(i) Phenylamine reacts with aqueous bromine to give compound F.

Describe the appearance of compound F. [1]

(ii) Phenylamine reacts with nitrous acid to form a diazonium salt.

State the conditions for this reaction. [1]

Answer 3

White precipitate and solid

Between 0 and 10 degrees celsius

Question 4

How does the basicity of phenylamine compare to that of ethylamine? Explain your answer.

Ref: 9701/41/M/J/16

Answer 4

phenylamine is less basic that ethylamine

the lone pair on N is delocalised over the ring…

…making it less available for reaction with a proton/ δ+ H

Question 5

Phenol can be synthesised from phenylamine in two steps.

State the reagents and conditions for steps 1 and 2.

Draw the structure of the intermediate compound E in the box above.

Answer 5

step 1: HNO2 OR (NaNO2 + HCl) at T ⩽ 10°C

step 2: boil/ heat in water