Question

Why is Bromobenzene unreactive?

Answer 1

Bromobenzene:

• Bromobenze has the chemical formula ${\mathrm{C}}_6{\mathrm{H}}_5\mathrm{Br}$.
• The resonating structures of Bromobenzene are given below:

Reactivity:

• In most ${\mathrm{S}}_{\mathrm{N}}1$ and ${\mathrm{S}}_{\mathrm{N}}2$ reactions, bromobenzene is unreactive.
• It is mostly due to the extremely strong carbon-bromine bond present.
• As a result, despite its capacity to exit the group, bromine will remain in the aromatic ring.
• As a result, in the case of ${\mathrm{S}}_{\mathrm{N}}2$, the ring structure prevents a backside assault, but in the case of ${\mathrm{S}}_{\mathrm{N}}1$, carbocation does not occur.
• Furthermore, phenyl carbocations are notoriously unstable.

Hence, Bromobenzene is unreactive.