Synthesis of Ethyl Acetate by Fisher Esterification

Introduction
If you want to do something good, you must first use its tools. In the field of chemical synthesis, it is the priority of chemists to find subtle ways to prepare specific compounds. Today, ethyl acetate is synthesized by Fisher esterification, which is an important way in organic synthesis.

Principle Description
Fisher esterification method, which is a method of reversibly reacting alcohol and carboxylic acid under the action of acidic catalysts to form esters. Taking the synthesis of ethyl acetate as an example, it is the reaction of ethanol and acetic acid. The reaction mechanism is that the acid first protonates the carbonyl group of the carboxylic acid to enhance the electrophilicity of the carbonyl group. The oxygen atom of ethanol then attacks the activated carbonyl group to form a tetrahedral intermediate. After the proton transfer and elimination reaction, ethyl acetate and water are formed. In this process, acidic catalysts can accelerate the reaction process, but because the reaction is reversible, it is necessary to try to promote the balance to the right to increase the yield of the product.

Experimental steps
First prepare the required things, ethanol, acetic acid, concentrated sulfuric acid (as a catalyst), and several glass instruments, such as flasks, condensers, separation funnels, etc. In the flask, pour ethanol and acetic acid in a certain proportion, slowly add concentrated sulfuric acid, and shake well while adding to prevent local overheating. Connect the condensation device, heat it in a water bath or an oil bath, and control the temperature to a suitable range to make the reaction proceed smoothly. During this period, pay close attention to the reaction phenomena, such as changes in liquid color and the formation of bubbles.

Product separation and purification
After the reaction is completed, the reaction liquid is cooled. Because the product is mixed with impurities such as unreacted raw materials, catalysts and water, it needs to be separated and purified. First, the liquid is separated by a separation funnel to remove the acid in the lower layer. The upper organic phase is washed with a saturated sodium carbonate solution to neutralize the residual acid; then washed with saturated salt water to reduce the solubility of the ester in water; finally dried with anhydrous magnesium sulfate to remove the residual water. Then, by distillation, the fraction in a specific boiling point range is collected to obtain pure ethyl acetate.

Conclusion
Ethyl acetate is synthesized by Fisher esterification. Although the steps are complicated, each step requires fine operation to obtain satisfactory results. This process not only highlights the charm of chemical synthesis, but also provides an important example for the preparation of organic compounds, which is of great significance for both industrial production and academic research.