Ibuprofen is a widely used nonsteroidal anti-inflammatory drug NSAID with the chemical formula C13H18O2. Its IUPAC name is 2- 4-isobutylphenyl propanoic acid. Retrosynthetic analysis is a technique used to break down complex molecules into simpler precursors, which can then be synthesized to obtain the target molecule.Retrosynthetic analysis of ibuprofen:Ibuprofen can be synthesized through several routes, but one of the most common methods involves the following key steps:1. Friedel-Crafts alkylation2. Reduction of the carbonyl group3. CarboxylationStarting materials and reaction steps:1. Friedel-Crafts alkylation:Starting materials: p-isobutylbenzene also known as cumene and propionyl chlorideCatalyst: Aluminum chloride AlCl3 or another Lewis acidReaction: p-isobutylbenzene reacts with propionyl chloride in the presence of a Lewis acid catalyst to form 4-isobutylacetophenone.2. Reduction of the carbonyl group:Starting material: 4-isobutylacetophenoneReducing agent: Sodium borohydride NaBH4 or another suitable reducing agentReaction: 4-isobutylacetophenone is reduced to form 4-isobutyl-1-phenylpropan-1-ol.3. Carboxylation:Starting material: 4-isobutyl-1-phenylpropan-1-olReagents: Carbon dioxide CO2 and a strong base such as potassium hydroxide KOH or sodium hydroxide NaOH Reaction: 4-isobutyl-1-phenylpropan-1-ol is treated with CO2 and a strong base to form the final product, ibuprofen.In summary, the retrosynthetic analysis of ibuprofen involves breaking it down into simpler precursors, such as p-isobutylbenzene and propionyl chloride. The synthesis of ibuprofen can then be achieved through a series of reactions, including Friedel-Crafts alkylation, reduction of the carbonyl group, and carboxylation.