Question

Provide a reasonable yet detailed mechanism for BOTH of the following transformations. Show all key resonance structures for the intermediates generated. at worden dan on no [2 x 7 marks] Propose a practical synthesis for the compounds shown from benzene. Use any other necessary organic or inorganic reagents. Show all intermediates formed to receive full credit. Assume any isomers formed can easily be separated. COOH [9 marks]

Answer 1

solution: O Nao me + Nach Meow ome Mechanism Mechanismi . o me Lome e TC) Nach + ome This is aromatic substitution nucleophilie substitution reaction. (SNAY). Here is not good leaving group as compared to Huorine. Hence reaction require harsh condition as compare to fluorine.. Mechanism: Step 1 step.2 3 carbocution.

& -&12- ] of double bond in Isomerisation step-t: This is under goes isomerisation of doubl acidic condition and heating to form more substituted. double bond. As we know more substituted double bond more stable than less substituted double bond terminal double bond). step.2: In acidic condition there is formation of 3 carbo- cation. The nucleophilic attack of benzene ring on 3 carbo- Step-3: Aromatisation of ring to give desired product. cation. Synthesis. NO2 HNO3/ H2 504 step-a == 0 + H2O + 8 sugh E] +O ENEO NO No2

cl2c 1.ea) Noz CH3cl, Alcl3 AlL3 Step-2 step-3 Du cool cool alk.kmnou - Step-4 ON Snc NaNO2 H4 TI step-5 step-6 соон EN YX = COOH -1 NEN- COM - 4 cuch Y step-7 Step 1: Nitration in HNO3 l H2SO4 to give nitrobenzene step-2: chlorination in cl2, Aldy to give 3-chloro-nitrobenzene step-3: Friedel craft alkylution in CH₃ d , Alca t o give Step 4: Oxidation of methyl group into -cool in alkaline kinnou. Step 5: Reduction of nitro into amine in Snce. step-6: Diazotisation reaction is NanozlHcle step-1 Sandmeyer reaction in cuch to give target molecule