Addition Reactions (continued)

Halogenation is an addition reaction where halogen (Cl2 and Br2) to an alkene or alkadiene.

In alkene:

In alkadiene:

Halogenation forms as a product vicinal halides, that is, two neighboring halogens.

This reaction is done by adding HX to the alkenes.

HX, where X is halogen.

Examples: HCl, HBr

In some cases we get two products. The "theoretically" expected should follow the Markovnikov Rule.

Markovnikov Rule - "In the addition reactions, hydrogen is added to the more hydrogenated double bond carbon".

Markovnikov Example:

However, we must be aware of the reactions where peroxide is present, because in these cases we use the rule Anti-Markovnikov, which is the inverse of Markovnikov.

Anti-Markovnikov example in case of addition of hydrogen bromide: