Addition of HI

Addition of HI Definition:

Treatment of alkanes with hydrogen iodide leads to the iodoalkanes. This reaction is called hydroiodonation.

Addition of HI Explained:

In this reaction, a hydrogen atom and a halogen are added across an alkene. The halogen (I) is ultimately positioned at the more substituted carbon, which verifies that this reaction takes place via an ionic mechanism known as Markovnikov rule. This ionic mechanism for hydrohalogenation has two steps:

1. Protonation of the alkanes to form the more stable carbocation
2. Nucleophilic attack – the chloride ion, formed in the previous step, functions as a nucleophile and attack carbon