Free Radical Addition to Alkenes

• In free radical addition reactions, atoms or groups add across the double bond of an alkene through a mechanism involving free radicals—highly reactive species with unpaired electrons.

Steps in Free Radical Addition

1) Initiation

• Free radicals are generated through the homolytic cleavage of a bond, typically induced by heat, light, or a catalyst.

• For instance, the homolytic cleavage of Br₂ can produce two bromine radicals.

2) Propagation

• A radical reacts with the alkene, forming a new radical.

• This newly formed radical continues the chain reaction, with addition occurring across the double bond.

3)Termination

• The reaction stops when two free radicals combine to form a stable product, thus terminating the chain reaction.