Radicals

Allylic Bromination of Cyclohexene

Background Colour:

Small (300 px) Medium (400 px) Large (500 px)

Removal of an H from an allylic position gives a much more stable delocalized allylic radical.

The allylic radical collects a bromine atom from a bromine molecule and produces a new bromine radical that can start a new series of reactions. Like the addition of HBr ,the reaction is a radical chain reaction, and only a small amount of Br₂ needs to break down to Br• to get the reaction going.