Isoamyl Acetate Synthesis through Fischer Reaction
Lesaca, Anna*, Lopez, Maria Flor, Lu, Ricardo, Magdurulan, Tricia
2Biology6, Department of Biology, College of Science, UST, Manila firstname.lastname@example.org
Esters are a type of functional group that causes distinguishable flavors or odors of some fruits. It can be synthesized by Fischer reaction, which is an acid-catalyzed reaction of an alcohol and carboxylic acid. One of the esters known for its characteristic banana flavor is the isoamyl acetate. By using Fischer reaction, Isoamyl acetate was produced by refluxing isoamyl alchol and acetic anhydride with the presence of sulfuric acid for 30 minutes. After cooling the mixture, cold water was added and it was transferred in a separatory funnel. It was then extracted with immiscible saturated sodium bicarbonate to hasten separation. The sodium bicarbonate layer was discarded and the organic layer was again extracted with sodium chloride to remove the acid. The sodium chloride layer was discarded. To fully isolate the organic layer (isoamyl acetate), anhydrous sodium sulfate was added to dry it. Based on the results and observation obtained, we were able to synthesize isoamyl acetate and we were able to solve for its percentage yield by determining the limiting reactant, and theoretical yield.
Keywords: Extract, Fischer reaction, Isoamyl acetate, Reflux, Synthesis
Esters are a compound formed from a carboxylic acid, RCOOH, and an alcohol, R’OH . They are most commonly known as a substances with pleasant smell. It can be easily synthesized through various methods. The method used in this experiment is Fischer reaction which is an acid-catalyzed synthesis of an alcohol and carboxylic acid. The acid and alcohol reactants are in equilibrium with the ester product. This was used to produce isoamyl acetate from the reaction of isoamyl alcohol and acetic anhydride. Sulfuric acid was used as a catalyst.
The set-up shown in figure 1 was used to reflux the 2.5ml isoamyl alcohol and 2.6ml acetic anhydride with 5d cone sulfuric acid and boiling chips for 30 minutes with a constant temperature between 75-85 degrees celsius.The heated reagents was then cooled down and was added with 5ml of cold water. The mixture was transferred to a separatory funnel as shown in figure 2. Another 2 ml of water was added. The solution was extracted with 10ml saturated sodium bicarbonate. The separatory funnel was capped after the bubbles ceased forming. It was gently swirled. Two distinct layers appeared. The lower sodium bicarbonate layer was discarded. The remaining organic layer was extracted again with 10ml saturated sodium chloride. The lower NaCl was discarded. The remaining organic isoamyl acetate layer was transferred into a clean beaker and was dried with anhydrous sodium sulfate. The solid sodium sulfate was removed through decantation.After that, the isoamyl acetate was weighed and the percentage yield was calculated.
Results and Discussion
Table 1 Data used
Table 1 shows how much volume of the reactants isoamyl alcohol and acetic anhydride was used in the experiment. It also shows their density and molecular weight which is needed for the calculation of the percentage yield.
Table 2 Results obtained
Mass yielded (g)
Colorless liquid, banana scent
Table 2 shows the mass of the product that was gathered and obtained from the experiment. It also states the observable description of the product and its molar mass.
The figure above shows the balanced chemical equation for the reaction of isoamyl alcohol and acetic anhydride producing isoamyl acetate and acetic acid. It shows that the...
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