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What is the major product formed when toluene reacts with Br2 in the presence of FeBr3 catalyst? Explain the reaction mechanism involved.

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The major product formed when toluene reacts with Br2 in the presence of FeBr3 catalyst is ortho-bromotoluene and para-bromotoluene. The reaction mechanism involved is electrophilic aromatic substitution  EAS .Here's the step-by-step reaction mechanism:1. Activation of the halogen: The FeBr3 catalyst reacts with Br2 to form a highly electrophilic bromine ion  Br+ . This is represented by the following equation:   FeBr3 + Br2  FeBr4- + Br+2. Formation of the sigma complex  arenium ion : The electrophilic bromine ion  Br+  attacks the aromatic ring of toluene, specifically at the ortho and para positions due to the electron-donating effect of the methyl group. This results in the temporary loss of aromaticity and the formation of a sigma complex  arenium ion .3. Deprotonation and regeneration of aromaticity: A base  usually the bromide ion, Br-  abstracts a proton from the carbon where the bromine ion was added, resulting in the regeneration of the aromatic ring and the formation of the major products, ortho-bromotoluene and para-bromotoluene.4. Regeneration of the catalyst: The FeBr4- ion releases a Br- ion, regenerating the FeBr3 catalyst.The overall reaction can be represented as:   Toluene + Br2  ortho-bromotoluene + para-bromotolueneThe major products are ortho-bromotoluene and para-bromotoluene due to the directing effect of the methyl group on the benzene ring, which favors electrophilic attack at the ortho and para positions. The para-bromotoluene is usually the major product because it is less sterically hindered than the ortho-bromotoluene.

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