Final answer:
In a halogenation reaction of benzene using chlorine with an electrophile made out of a different halogen like bromine, the reaction proceeds if the electrophile is strong enough. The product will be a halogenated benzene derivative with the halogen dictated by the electrophile used.
Step-by-step explanation:
When benzene undergoes halogenation, a halogen atom, such as chlorine or bromine, is substituted for one of the hydrogen atoms on the benzene ring in the presence of a strong electrophile. If chlorine is used as the halogen and the electrophile contains a different halogen, such as bromine, the result will depend on the conditions and the reactivity of the electrophiles involved.
In the halogenation of benzene, the aromatic ring acts as a nucleophile, attacking the strong electrophile. The intermediate formed will subsequently lose a hydrogen cation to regain its aromaticity, resulting in the formation of an aryl halide. If an electrophile from a different halogen is introduced, the reaction will still proceed as long as the electrophile is strong enough to be attacked by the benzene ring.