Hydroboration-Oxidation Reaction in Chemistry
by Yuvi K - December 17, 2023
Introduction to Hydroboration-oxidation reaction in Chemistry
Hydroboration–oxidation reaction is a two-step process used in organic chemistry for shifting the double bond of alkynes. Its a very general method for the synthesis of alcohols from alkenes and alkynes. This reaction was developed by Herbert C. Brown in the early 1950s. This reaction undergoes two steps known as hydroboration followed by oxidation.
What is Hydroboration?
Hydroboration is a process of addition of boron trihydride (BH3) to a double bond of an alkene. BH3 accepts two electrons provided by alkene and forms a dialkyl borane. Borane acts as a Lewis acid by accepting two electrons from the pi-bond of the alkene and forms a stable sigma bond with it. Borane anion or hydrated borane formed is known also to undergo hydrolysis in presence of water to form alcohol.
What is Oxidation?
Oxidation is a chemical process which involves the loss of electrons from a molecule or an atom. The electrons lost are received by an oxidizing agent. Reactive oxygen atom such as hydroperoxide or a permanganate ion is usually used as an oxidizing agent. Oxidation process either leads to an increase in the oxidation state of a molecule or causes an atom to be oxidised.
Reagents used in Hydroboration-oxidation reaction
The chemicals used for Hydroboration-Oxidation process are
| Reagents | Function |
|---|---|
| Borane(BH3) | To add a hydrogen atom to the double bond of alkene |
| Hydroperoxides(R’OOH) | Acts as oxidizing agent |
| Lithium Aluminium Hydride (LiAlH4) | Reduces hydroperoxide to alcohols |
Advantages of Hydroboration-oxidation reaction
Hydroboration-Oxidation process is known to be an effective reaction to generate alcohols from alkenes and alkynes in a consecutively simple and cost effective manner. The resulting alcohols formed are usually better than those formed by other methods like LiAlH4 reaction as they do not require any further reaction. It also helps in refining the selectivity of the reaction.
Applications of Hydroboration- Oxidation Reaction
Hydroboration- Oxidation reaction is used in the synthesis of several organic substances such as alcohols, ketones, carboxylic acids, etc.
Additionally, it is also used in the production of polystyrene, in the manufacture of dyes, pharmaceuticals, surfactants, etc. It can also be used in the synthesis of organosilicon compounds for uses in high-performance polymers, sealants, lubricants, paints, and plastics.
Safety Measures While Handling Hydroboration-Oxidation Reagents
Hydroboration-Oxidation reaction reagents are usually associated with high risk and therefore it is extremely important to take certain safety measures while handling them. It is advised to wear proper eye and hand protection while performing the reaction. Before handling any of the reagents, it should be ensured that the reactants are in their proper form and not deteriorated or contaminated.
Conclusion
In this article, we saw how the process of Hydroboration-Oxidation reaction is used in organic chemistry, its mechanism, reagents, applications and safety measures required in performing the reaction. This process helps us to synthesise complex organic compounds in an easy way without any additional cost. Hence, this is definitely an exciting process to use for synthesising organic molecules.
