The key difference between alkoxymercuration and oxymercuration is that alkoxymercuration forms an ether from an alkene and alcohol, whereas Oxymercuration forms neutral alcohol from an alkene.
Alkoxymercuration or alkoxymercuration-demercuration is a chemical reaction that can be used to produce an ether from an alkene. Oxymercuration, on the other hand, is a chemical reaction where an electrophilic addition mechanism takes place, transforming an alkene into neutral alcohol.
CONTENTS
1. Overview and Key Difference
2. What is Alkoxymercuration
3. What is Oxymercuration
4. Similarities – Alkoxymercuration and Oxymercuration
5. Alkoxymercuration vs Oxymercuration in Tabular Form
6. Summary – Alkoxymercuration vs Oxymercuration
What is Alkoxymercuration?
Alkoxymercuration or alkoxymercuration-demercuration is a chemical reaction that can be used to produce an ether from an alkene. In other words, it is a reaction in which an alkene reacts with an alcohol (in the presence of mercuric acetate). This initially gives us an alkoxymercury intermediate, which then produces an ether followed by the reduction with sodium borohydride.
In this reaction, first, an organic compound consisting of an alkene reacts with alcohol and mercuric acetate. We generally use a mercury-containing reagent in this reaction. Thereafter, the intermediate produced during the reaction further reacts with a reducing agent known as sodium borohydride. Ultimately, this combination gives an ether as the final organic product. We can name ethers as the organic derivatives of water in which both hydrogen atoms are replaced by two carbon-based groups such as diethyl ether.
A common alkoxymercuration-demercuration reaction is a reaction between cyclohexene and ethanol and mercuric acetate. The cyclohexene molecule has a carbon-carbon double bond that is required for this reaction. Since we use ethanol as the alcohol, the final product will appear as a combination of ethanol moiety (without a proton) and the cyclohexene molecule. Therefore, we are getting a new carbon-hydrogen bond other than the carbon-i=oxygen bond of the ether molecule.
What is Oxymercuration?
Oxymercuration is a chemical reaction in which an electrophilic addition mechanism takes place, transforming an alkene into a neutral alcohol. In this process, we can observe the reaction between an alkene and mercuric acetate in an aqueous solution. This yields the addition of an acetoxymercury group and an OH group across the double bond.
Figure 01: A Chemical Reaction involving Oxymercuration
During the Oxymercuration process, carbocations do not form. Therefore, there are rearrangement steps as well. This reaction takes place according to Markonikov’s rule. Moreover, it is an anti-addition reaction. This means the OH group will always get added to the more substituted carbon atom and the two groups tend to be trans to each other, respectively.
Usually, Oxymercuration reaction is followed by reductive demercuration reaction; hence we call it an Oxymercuration-reduction reaction. Practically, this reduction reaction is more common than Oxymercuration reaction.
What are the Similarities Between Alkoxymercuration and Oxymercuration?
- Alkoxymercuration and oxymercuration reactions follow Markonikov’s rule.
- Both reactions involve an alkene as a reactant.
- These reactions require mercuric acetate.
- They are important synthetic steps in some industrial processes.
What is the Difference Between Alkoxymercuration and Oxymercuration?
Alkoxymercuration and oxymercuration are important synthetic steps in some industrial processes. The key difference between alkoxymercuration and oxymercuration is that alkoxymercuration forms an ether from an alkene and an alcohol, whereas oxymercuration forms neutral alcohol from an alkene.
The below infographic presents the differences between alkoxymercuration and oxymercuration in tabular form for side by side comparison.
Summary – Alkoxymercuration vs Oxymercuration
Alkoxymercuration and oxymercuration follow Markonikov’s rule to produce different products from alkenes and mercuric acetate. The key difference between alkoxymercuration and oxymercuration is that alkoxymercuration forms an ether from an alkene and alcohol, whereas oxymercuration forms neutral alcohol from an alkene.