The synthesis of ibuprofen from 2-methylpropylbenzene isobutylbenzene and carbon dioxide typically involves a two-step process: Friedel-Crafts acylation and subsequent carboxylation.1. Friedel-Crafts Acylation: In this step, 2-methylpropylbenzene reacts with acetyl chloride in the presence of a Lewis acid catalyst, such as aluminum chloride AlCl3 , to form 2- 4-isobutylphenyl propanoyl chloride.Optimal conditions for this reaction include:- Temperature: 0 to 25C preferably around 0C to minimize side reactions - Molar ratio: Excess acetyl chloride and aluminum chloride to ensure complete reaction- Solvent: Anhydrous conditions using a non-polar solvent like dichloromethane or chloroform2. Carboxylation: In this step, 2- 4-isobutylphenyl propanoyl chloride reacts with carbon dioxide CO2 to form ibuprofen.Optimal conditions for this reaction include:- Temperature: 100 to 150C to facilitate the reaction - Pressure: High pressure 10-30 atm to increase the solubility of CO2 in the reaction mixture- Base: A strong base like sodium or potassium hydroxide to facilitate the reaction- Solvent: Polar aprotic solvents like dimethylformamide DMF or dimethyl sulfoxide DMSO The yield and purity of the final product ibuprofen are affected by the reaction conditions in the following ways:- Temperature: Maintaining optimal temperatures in both steps ensures that the reactions proceed efficiently and minimizes side reactions that can reduce yield and purity.- Molar ratio: Using excess reactants and catalysts helps drive the reactions to completion, increasing the yield of the desired product.- Pressure: High pressure in the carboxylation step increases the solubility of CO2, promoting the formation of ibuprofen and improving yield.- Solvent: Choosing appropriate solvents for each step ensures that the reactants and intermediates are soluble, facilitating the reactions and improving yield and purity.After the synthesis, purification steps such as recrystallization or chromatography can be employed to further improve the purity of the final ibuprofen product.