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What is the mechanism of the Friedel-Crafts alkylation reaction of benzene with tert-butyl chloride in the presence of aluminum chloride catalyst?

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The Friedel-Crafts alkylation reaction is an electrophilic aromatic substitution reaction in which a benzene ring reacts with an alkyl halide in the presence of a Lewis acid catalyst, such as aluminum chloride  AlCl3 . In this case, the reaction involves benzene and tert-butyl chloride  t-BuCl .Here is the step-by-step mechanism for the Friedel-Crafts alkylation of benzene with tert-butyl chloride using an aluminum chloride catalyst:1. Activation of the alkyl halide: The Lewis acid catalyst, AlCl3, coordinates with the halogen atom  chlorine  in the tert-butyl chloride molecule, forming a complex. This interaction polarizes the carbon-chlorine bond, making the carbon atom more electrophilic.t-BuCl + AlCl3  t-BuClAlCl32. Generation of the electrophile: The bond between the carbon and chlorine atoms in the tert-butyl chloride molecule breaks, resulting in the formation of a tert-butyl carbocation  t-Bu+  and an AlCl4- ion.t-BuClAlCl3  t-Bu+ + AlCl4-3. Electrophilic attack on benzene: The electrophilic tert-butyl carbocation  t-Bu+  attacks the benzene ring, breaking one of the pi bonds in the aromatic ring. This results in the formation of a non-aromatic, positively charged cyclohexadienyl cation  Wheland intermediate  with the tert-butyl group attached to the ring.Benzene + t-Bu+  t-Bu-Cyclohexadienyl cation4. Deprotonation and regeneration of the catalyst: A base, usually the AlCl4- ion, abstracts a proton from the cyclohexadienyl cation, restoring the aromaticity of the ring and generating the alkylated benzene product  tert-butylbenzene  and regenerating the AlCl3 catalyst.t-Bu-Cyclohexadienyl cation + AlCl4-  tert-butylbenzene + HCl + AlCl3Overall, the Friedel-Crafts alkylation reaction of benzene with tert-butyl chloride in the presence of an aluminum chloride catalyst results in the formation of tert-butylbenzene.
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