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What is the step-by-step mechanism involved in the synthesis of ibuprofen from 2-methylpropylbenzene and carbon dioxide and what are the reagents and conditions required for each step?

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The synthesis of ibuprofen from 2-methylpropylbenzene  isobutylbenzene  and carbon dioxide involves several steps. Here is a step-by-step mechanism with the reagents and conditions required for each step:1. Friedel-Crafts Alkylation:Reagents: 2-methylpropylbenzene  isobutylbenzene , propionyl chloride, aluminum chloride  AlCl3 Conditions: Anhydrous conditions, room temperatureMechanism: The AlCl3 acts as a Lewis acid catalyst, activating the propionyl chloride by forming a complex with the carbonyl oxygen. This generates an electrophilic acyl species, which then reacts with the isobutylbenzene at the aromatic ring through an electrophilic aromatic substitution reaction. The AlCl3 is then regenerated, and the desired 2- 4-isobutylphenyl propanoyl chloride is formed.2. Hydrolysis:Reagents: WaterConditions: Heating under refluxMechanism: The 2- 4-isobutylphenyl propanoyl chloride reacts with water, replacing the chloride group with a hydroxyl group to form 2- 4-isobutylphenyl propanoic acid  ibuprofen precursor .3. Kolbe-Schmitt Reaction  Carboxylation :Reagents: Carbon dioxide  CO2 , sodium hydroxide  NaOH , hydrochloric acid  HCl Conditions: High pressure  100-150 atm , high temperature  150-200C Mechanism: The ibuprofen precursor is first deprotonated by NaOH to form a carboxylate ion. The carboxylate ion then reacts with CO2 under high pressure and temperature to form a new carboxylate group at the ortho position of the aromatic ring. The product is then protonated by HCl to form the final ibuprofen product, 2- 4-isobutylphenyl propionic acid.These steps outline the synthesis of ibuprofen from 2-methylpropylbenzene and carbon dioxide. Note that there are other methods to synthesize ibuprofen, but this is one of the most common routes.
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