Ethyl acetate

Ethyl acetate, an organic compound, is an ester of acetic acid and ethanol. Ethyl acetate is widely used as a solvent in the synthesis of many significant organic compounds. The applications of ethyl acetate are extensive, from acting as a flavoring agent in the food industry to cleaning agent in the textile industry. In this article, we will be learning about different aspects of ethyl acetate like structure, synthesis, physical properties, chemical reactions, and applications.

Structure of ethyl acetate

The molecular formula of ethyl acetate is CH3COOCH2CH3 which can be simplified as C4H8O2. The carbon atom present in the carbonyl group exhibits sp2 hybridization, whereas the other carbon atoms exhibit sp3 hybridization. Hence, ethyl acetate contains one unsaturated double bond.
The structural formula and ball-stick model of ethyl acetate are as follows.

Synthesis of ethyl acetate

Count de Lauraguais synthesized ethyl acetate for the first time in 1759 by performing a distillation reaction for the mixture of acetic acid and ethanol. The industrial production of ethyl acetate is carried out using the Fischer esterification reaction. The various methods of synthesizing ethyl acetate are given below.

1. Fischer esterification reaction
The procedure involved in synthesizing ethyl acetate with the help of the Fischer esterification reaction is as follows.

● The reactants involved in the Fischer esterification reaction are acetic acid and ethanol. However, an acid catalyst like concentrated sulphuric acid is essential for the reaction to take place.
● Acetic acid and ethanol are made to undergo reflux in the presence of concentrated sulphuric acid.
● The acetic acid and ethanol mixture is converted into ethyl ester (65% yield at room temperature).
The reaction for the synthesis of ethyl acetate via the Fischer esterification method is given below.
CH3COOH + CH3CH2OH 🡪 CH3COOCH2CH3 + H2O

2. Dehydrogenation of ethanol
The catalytic dehydrogenation of ethanol is a unique process used to synthesize ethyl acetate industrially. Compared to the Fischer esterification reaction method, the dehydrogenation of ethanol is more economical. In addition, the dehydrogenation of ethanol occurs in the presence of copper and at higher temperatures (below 250 °C).

3. Tishchenko Reaction
Another popular method used to synthesize ethyl acetate commercially is the Tishchenko reaction. In this reaction, two equivalents of acetaldehyde molecules are made to react with each other in the presence of any alkoxide catalyst. For example, the Tischenko reaction is as follows.
2CH3CHO →
CH3COOCH2CH3 (in the presence of alkoxide)

Physical properties of ethyl acetate

The simplest carboxylate ester is ethyl acetate. Ethyl acetate is a colorless liquid with a pleasantly sweet and fruity odor. The physical properties of ethyl acetate are as follows.

Chemical reactions of ethyl acetate

Ethyl acetate is reactive towards certain chemicals and reagents. The most common chemical reactions of ethyl acetate are explained below.

1. Hydrolysis of ethyl acetate
Hydrolysis of ethyl acetate refers to the process of breakdown of bonds in the presence of water molecules. The hydrolysis of ethyl acetate results in acetic acid (carboxylic acid and ethanol (alcohol). HCl and NaOH are used to accelerate the hydrolysis of ethyl acetate.
CH3COOC2H5 + H2O CH3COOH + C2H5OH

2. The reaction of ethyl acetate with NaOH
Ethyl acetate reacts with sodium hydroxide (strong base) and results in sodium acetate and ethanol formation.
CH3COOC2H5 + NaOH CH3COONa + C2H5OH

3. Claisen condensation of ethyl acetate
Ethyl acetate undergoes a Claisen condensation reaction to yield ethyl acetoacetate and ethanol. Claisen condensation of ethyl acetate takes place in the presence of NaOCH2CH3 and H3O+ ions. This reaction takes place under anhydrous conditions.

Applications of ethyl acetate

Ethyl acetate is one of the essential solvents in laboratories and manufacturing industries. Consequently, it has an extensive range of applications which are as follows.

● Ethyl acetate is highly economical and readily available. Hence, it is widely used as a diluent and solvent.
● Ethyl acetate is harmless and offers less toxicity. Hence, it is used to decaffeinate tea leaves and coffee beans.
● Ethyl acetate is used in the preparation of perfumes and jellies because of its fruity odor.
● Ethyl acetate acts as a hardener or activator in paints.
● Ethyl acetate is added to nail polish removers, which evaporates immediately, leaving behind the fruity scent. The same is the case with perfumes.
● Ethyl acetate is widely used as a solvent to extract plant compounds. Ethyl acetate is thus a common solvent used in extractions and column chromatography.
● The use of ethyl acetate as a reaction solvent because it is highly susceptible to chemical reactions like condensation, hydrolysis, and transesterification.