Radical substitution

In organic chemistry, a radical-substitution reaction is a substitution reaction involving free radicals as a reactive intermediate.^[1]

The reaction always involves at least two steps, and possibly a third.

In the first step called initiation (2,3), a

with another radical species. If the reaction is not terminated, but instead the radical group(s) go on to react further, the steps where new radicals are formed and then react are collectively known as propagation (4,5). This is because a new radical is created, able to participate in secondary reactions.

Radical substitution reactions

In

.

More radical substitutions are listed below:

• The
  hydroxyl
  group for a proton.
• The
  Wohl–Ziegler reaction
  involves allylic bromination of alkenes.
• The Hunsdiecker reaction converts silver salts of carboxylic acids to alkyl halides.
• The Dowd–Beckwith reaction involves ring expansion of cyclic β-keto esters.
• The Barton reaction involves synthesis of nitrosoalcohols from nitrites.
• The Minisci reaction involves generation of an alkyl radical from a carboxylic acid and a silver salt, and subsequent substitution at an aromatic compound

References