Hydrolysis mechanism of ethyl acetate

Ethyl acetate, as a common organic compound, its hydrolysis reaction is of great significance in the field of chemistry. This reaction can occur under acidic or basic conditions, and each has its own unique mechanism.

Hydrolysis mechanism under acidic conditions
In an acidic environment, the first is the combination of water molecules and hydrogen ions to form hydrated hydrogen ions ($H_3O ^ + $). The carbonyl oxygen in the ethyl acetate molecule ($CH_3COOC_2H_5 $) has a certain electronegativity, which attracts hydrogen atoms in the hydrated hydrogen ion, which in turn makes the carbonyl carbon partially positively charged. At this time, the water molecule acts as a nucleophile, and the lone pair of electrons on its oxygen atom attacks the carbonyl carbon to form a tetrahedral intermediate. Subsequently, the intermediate undergoes proton transfer, causing the oxygen atom connected to the ethyl ester group to be positively charged. This positive charge prompts the carbon-oxygen bond to break, the ethyl ester group leaves to form ethanol ($C_2H_5OH $), and the remaining part is converted to acetic acid ($CH_3COOH $). The whole process can be summarized as a nucleophilic addition-elimination reaction, and the reaction is reversible, and the degree of reaction is affected by factors such as the concentration of the reactants and temperature.

Hydrolysis mechanism under basic conditions
Under basic conditions, hydroxide ions ($OH ^ - $) have strong nucleophilic properties, directly attacking the carbonyl carbon of ethyl acetate to form tetrahedral intermediates. Unlike acidic conditions, the oxygen atoms in this intermediate are negatively charged and unstable. Subsequently, the carbon-oxygen bond connecting the ethyl ester group is broken, and the ethyl ester group leaves to form the ethanol negative ion ($C_2H_5O ^ - $). The ethanol negative ion quickly grabs a proton from the water to form ethanol, while the other part forms the acetate ion ($CH_3COO ^ - $). Due to the continuous consumption of acetic acid by hydroxide ions, the reaction equilibrium shifts to the right, and the hydrolysis of ethyl acetate under alkaline conditions is more complete, which is significantly different from the reversible reaction under acidic conditions.

In summary, although the hydrolysis mechanism of ethyl acetate under acidic and alkaline conditions involves nucleophilic attack and intermediate formation, due to differences in the reaction environment, the reaction process, product form and reaction degree are different. These differences have important application value in the fields of organic synthesis and chemical analysis.