Lawsone is the dye that is extracted from the henna plant, Lawsonia inermis. Although its natural colour is yellow, lawsone reacts with the proteins in hair and skin to produce the characteristic brown henna colour.

Lawsone can readily be reduced to 1,2,4-trihydroxynaphthalene, compound A.

(a)

(i)

Name three functional groups in lawsone.

(a)

(i)

Name the functional groups, in addition to the benzene ring, present in a phenolphthalein molecule.

[ 1 ]

(a)

(i)

Explain why butylamine is basic.

[ 1 ]

(ii)

Write an equation to show butylamine reacting as a base.

[ 1 ]

(a)

Isocyanic acid, HNCO , can form cyanuric acid, $\mathrm{C}_{3} \mathrm{H}_{3} \mathrm{~N}_{3} \mathrm{O}_{3}$ , under certain conditions.
$\mathrm{C}_{3} \mathrm{H}_{3} \mathrm{~N}_{3} \mathrm{O}_{3}$ has a cyclic structure containing alternating carbon and nitrogen atoms in the ring system.

Suggest a structure for cyanuric acid.

[ 1 ]

[Maximum number: 2]

Nitrobenzene, $\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{NO}_{2}$ , can be reduced to phenylamine, $\mathrm{C}_{6} \mathrm{H}_{5} \mathrm{NH}_{2}$ , in acid solution in a two step process.

(a)

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

[ 2 ]

[Maximum number: 2]

Compound G is a naturally occurring aromatic compound that is present in raspberries.

compound G

(a)

Identify the functional groups present in compound G.

[ 2 ]

[Maximum number: 4]

Methoxetamine is a derivative of the pharmaceutical drug, ketamine.

methoxetamine

(a)

(i)

Name two functional groups in methoxetamine, in addition to the aryl group.

[ 4 ]

(a)

Aminolaevulinic acid is involved in the synthesis of haemoglobin and chlorophyll.

aminolaevulinic acid

Name the three functional groups in aminolaevulinic acid.

[ 2 ]

(a)

Four compounds, E, F, G and H, are isomers of each other.

Each compound contains an aromatic ring and two functional groups from the following list.
- alcohol
- amide
- amine
- carboxylic acid
- ester
- phenol

[ 6 ]

(i)

Which of these functional groups react readily with cold HCl(aq) ?

[ 1 ]

(ii)

Which of these functional groups react readily with cold NaOH(aq) ?

The molecular formula of the four isomers, E, F, G and H, is $\mathrm{C}_{8} \mathrm{H}_{9} \mathrm{NO}_{2}$ . All four compounds are insoluble in water. Table 1 shows their solubilities in acid or alkali.

Table 1

[ 1 ]

(iii)

Use this information to suggest the two functional groups, taken from the list on page 10, that each compound contains.

[ 4 ]

(a)

Compound H has the structural formula $\mathrm{CH}_{2}=\mathrm{CHCH}\left(\mathrm{NH}_{2}\right) \mathrm{COOH}$ .

[ 2 ]

(i)

Name all the functional groups in H.

[ 2 ]