Bouveault blanc reduction

It is a chemical reactionin which esters are reduced to primary alochols using absolute ethanol and sodium metal.

1. Bouveault – Blanc Reduction Presented By: Gandham Malasree M Pharmacy Regd no: 620209502002 Dept of Pharmaceutical Chemistry AU COLLEGE OF PHARMACEUTICAL SCIENCES, VISAKHAPATNAM

2. BOUVEAULT – BLANC REDUCTION It is a chemical reactionin which esters are reduced to primary alochols using absolute ethanol and sodium metal. This reaction was first proposed by LOUIS BOUVEAULT & GUSTAVE LOUIS BLANC in the year 1903. They demonstrated the reduction of ethyl oleate and n-butyl oleate to oleyl alcohol. C2H50H / Na It is a chemical reactionin which esters are reduced to primary alochols using absolute ethanol and sodium metal. This reaction was first proposed by LOUIS BOUVEAULT & GUSTAVE LOUIS BLANC in the year 1903. They demonstrated the reduction of ethyl oleate and n-butyl oleate to oleyl alcohol. GENERAL REACTION

3. Reagents Sodiun metal (Na + electron) Metal reducing agent is LITHIUM ALUMINIUM HYDRIDE (LiAlH4) it is used for laboratory scale reactions. Solvated electron acts as a nucleophile Solvents Ethanol(C2H5OH) Protonated solvent This method is an inexpensive substitute for  LAH  reductions of esters in industrial production, and was the only alternative prior to the development of the metal hydride reducing agents. This dissolving metal reduction is also related to the  Birch Reduction .

4. MECHANISM It is a single electron transfer mechanism. Sodium  serves as single electron reducing agent and ethyl alcohol is the proton donor. If no proton donor is available, dimerization will take place, as the  acyloin condensation . Electron transfer& radical formation Protonation Second electron transfer & carbanion formation Protonation Removal of one molecule of alcohol Electron transfer Protonation Electron transfer Protonation

5. Examples

6. It involves the encapsulating the alkali metal into a silica gel which has a safety and yield profile similar to hydride reagents. Another modification involves use of sodium dispersion. Modifications This approach to reducing esters was widely used prior to the availability of hydride reducing agents such as LiAlH4 and related agents. It requires vigorous reaction conditions and has a significant risk of fires.

7. APPLICATIONS It is used to prepare two different types of alcohols. It is used in preparation of alcohols in large amounts. Used in personal care application. Alcohol elevates the extracellular dopamine in brain. Life saving drugs.