The reaction between benzene and bromine to form bromobenzene is an example of electrophilic aromatic substitution. The mechanism involves the following steps:1. Formation of the electrophile: Bromine Br2 reacts with a Lewis acid catalyst, such as iron III bromide FeBr3 or aluminum bromide AlBr3 , to form a highly electrophilic bromine ion Br+ . The catalyst polarizes the bromine molecule, making one of the bromine atoms electron-deficient. Br2 + FeBr3 Br+ + FeBr4-2. Attack of the electrophile: The electron-rich benzene ring donates a pair of electrons from one of its pi bonds to the electrophilic bromine ion Br+ , forming a sigma bond between the bromine and the carbon atom in the ring. This results in the formation of a positively charged cyclohexadienyl cation also known as an arenium ion or Wheland intermediate and disrupts the aromaticity of the benzene ring.3. Deprotonation: A base, usually the halogen anion generated in the first step Br- , abstracts a proton from the cyclohexadienyl cation, regenerating the aromaticity of the benzene ring and forming bromobenzene as the final product. C6H5Br+HBr- C6H5Br + HBr4. Regeneration of the catalyst: The hydrogen bromide HBr formed in the previous step reacts with the iron III bromide FeBr4- to regenerate the catalyst FeBr3 and release a bromide ion Br- . HBr + FeBr4- FeBr3 + Br-Overall, the reaction can be summarized as: C6H6 + Br2 C6H5Br + HBrThe reaction mechanism involves the formation of an electrophile, attack of the electrophile on the benzene ring, deprotonation to restore aromaticity, and regeneration of the catalyst.