What is the Difference Between Oxymercuration and Demercuration?

The main difference between oxymercuration and demercuration lies in the reactions they involve and the intermediates they form.

Oxymercuration is a chemical reaction in which an electrophilic addition mechanism takes place, transforming an alkene into a neutral alcohol. It involves the use of mercuric acetate, which dissociates into a mercuric cation, and this electrophilic cation is attacked by the alkene double bond. The oxymercuration reaction follows Markovnikov's regioselectivity, and the carbocation intermediate formed is stabilized by a mercurium ion bridge, preventing rearrangements.

Demercuration is a reaction in which an alkene converts into a mercury (Hg2+) salt and an organomercury intermediate. In the context of oxymercuration-demercuration, this step involves the demercurization of the organomercury intermediate formed in the previous step, which is later converted into the final alcohol product.

In summary, oxymercuration involves the addition of a mercuric cation to an alkene, transforming it into a neutral alcohol, while demercuration involves the conversion of an alkene into an organomercury intermediate. The oxymercuration-demercuration reaction pathway is used to produce alcohols with the advantage of preventing possible rearrangements.

Comparative Table: Oxymercuration vs Demercuration

Oxymercuration and demercuration are two steps in a reaction pathway used to produce alcohols from alkenes. Here is a comparison between the two steps:

Overall, the oxymercuration-demercuration mechanism follows Markovnikov's Regioselectivity, meaning that the hydroxyl group (OH) is added to the carbon with the most hydrogen atoms. The reaction is useful because strong acids are not required, and carbocation rearrangements are avoided.