The synthesis of ibuprofen from 2-methylpropylbenzene also known as isobutylbenzene involves a series of reactions. Here is the step-by-step mechanism:1. Friedel-Crafts Alkylation: The first step is the Friedel-Crafts alkylation of isobutylbenzene with propionyl chloride in the presence of a Lewis acid catalyst, such as aluminum chloride AlCl3 . This reaction forms 2- 4-isobutylphenyl propanoyl chloride.2. Hydrolysis: The next step is the hydrolysis of the acyl chloride formed in the previous step. This can be done by treating the compound with water or a weak base like sodium hydroxide NaOH to form 2- 4-isobutylphenyl propanoic acid, which is the ibuprofen precursor.3. Carboxylation: The third step is the carboxylation of the ibuprofen precursor using carbon dioxide CO2 . This can be achieved by heating the precursor in the presence of a strong base like sodium hydroxide NaOH under high pressure and temperature. This reaction forms the sodium salt of ibuprofen.4. Acidification: The final step is the acidification of the sodium salt of ibuprofen. This can be done by treating the salt with a strong acid like hydrochloric acid HCl to form the final product, ibuprofen.To optimize the reaction and increase the yield of ibuprofen, the following strategies can be employed:1. Use of excess reactants: Using an excess of propionyl chloride and isobutylbenzene in the Friedel-Crafts alkylation step can help drive the reaction to completion and increase the yield of the product.2. Temperature and pressure control: Maintaining optimal temperature and pressure conditions during the carboxylation step can help increase the yield of the sodium salt of ibuprofen. Typically, a temperature of 130-150C and a pressure of 10-15 atm are used.3. Purification: Purifying the intermediate products at each step can help remove impurities and side products, which can improve the overall yield of the final product.4. Catalyst optimization: Using an appropriate catalyst and optimizing its concentration can help improve the efficiency of the reactions and increase the yield of ibuprofen. For example, using a more effective Lewis acid catalyst in the Friedel-Crafts alkylation step can help improve the reaction rate and yield.5. Reaction monitoring: Monitoring the progress of each reaction step using analytical techniques like thin-layer chromatography TLC or high-performance liquid chromatography HPLC can help determine the optimal reaction time and conditions for each step, which can improve the overall yield of ibuprofen.