Question

What happens when phenol is treated with bromine?

Answer 1

1. Phenol (${\mathrm{C}}_6{\mathrm{H}}_6\mathrm{O}$) is a powerful activating group in the form of $\mathrm{OH}$ and there is an electrophilic aromatic substitution at the ortho and para position.

The reaction mechanism between the phenol and bromine is as follows:

1. The product of the reaction between Phenol and Bromine is 2,4,6-tribromophenol.
2. One lone pair of the oxygen atoms for the $\mathrm{OH}$ group react under resonance with the benzene ring that has the capability to increase the electron density at the ortho and para position of this ring.
3. In this way, the benzene ring is activated towards electrophilic substitution of ${\mathrm{Br}}^{+}$ by the ${\mathrm{R}}^{+}$effect.