Ester Hydrolysis with H2SO4

The reaction of an ester with water, catalyzed by the hydroxonium ion (H₃O⁺) present in the acidic solution, involves breaking an ester bond using sulfuric acid. A large excess of water can be used, as the dilute acid provides both the acid catalyst and the water. The reaction is reversible, so an excess of water is necessary to shift the equilibrium towards the formation of carboxylic acid and alcohol.

Example of Acid Hydrolysis

C₆H₅COOCH₃ + H₂O + H₂SO₄ → C₆H₅COOH + CH₃OH

Mechanism of Hydrolysis of Esters with H₂SO₄

The mechanism of ester hydrolysis with H₂SO₄ is as follows:

Protonation: H₂SO₄ protonates the carbonyl oxygen of the ester, forming an intermediate that is susceptible to nucleophilic attack by water.

Nucleophilic Attack: Water attacks the carbonyl carbon, breaking the carbon-oxygen bond and forming a tetrahedral intermediate.

Tetrahedral Intermediate Breakdown: The tetrahedral intermediate breaks down, reforming the carbonyl group and releasing an alcohol molecule.

Proton Transfer: H₂SO₄ donates a proton to the leaving alcohol molecule, forming an alcohol molecule and regenerating the H₂SO₄ catalyst.

Overall reaction is:

RCOOR’ + H₂O + H₂SO₄ → RCOOH + R’-OH + H₂SO₄

This reaction is commonly used to synthesize certain types of ethers and dehydrate alcohols to alkenes.

Hydrolysis of EstersEster Hydrolysis with NaOH

Ester hydrolysis is breaking down an ester into its constituent carboxylic acid and alcohol this takes place in an acidic or basic medium. The mechanisms of acid-catalyzed ester hydrolysis differ, with base-catalyzed hydrolysis being irreversible.

In this article, we look into what ester is, the hydrolysis of ester, its reaction, mechanism, application, etc.

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