Methyl red can be synthesised as shown in Fig. 7.1. [Figure 7.1 showing the reaction scheme starting from compound P (2-nitrobenzoic acid), going through step 1 to Q, then Q reacts to form R and S (both are reactants in step 3), then R and S react in step 3 to form Methyl red. Structure P is benzoic acid with a nitro group at the ortho position.]

1. (a)(i)Give the systematic name of P.[1]
2. (a)(ii)P can be synthesised as shown in Fig. 7.2. [Figure 7.2 showing methylbenzene (toluene) reacting to form 2-nitromethylbenzene, then this reacting to form P (2-nitrobenzoic acid)] Suggest reagents and conditions for this reaction.[1]
3. (a)(iii)A student attempts to synthesise P by an alternative route, as shown in Fig. 7.3. Compound T is the major product in this reaction rather than P. [Figure 7.3 showing benzoic acid reacting with conc. HNO₃ and conc. H₂SO₄ to form T (3-nitrobenzoic acid) and P (2-nitrobenzoic acid as minor)] Explain why T is the major product in this reaction.[1]
4. (b)(i)S reacts in a similar way to phenol in step 3. Draw the structures of Q, R and S in the boxes in Fig. 7.1.[3]
5. (b)(ii)Suggest reagents and conditions for steps 1 and 2 in Fig. 7.1. step 1 step 2[3]

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