Lesaca, Anna*, Lopez, Maria Flor, Lu, Ricardo, Magdurulan, Tricia
2Biology6, Department of Biology, College of Science, UST, Manila annalesaca@yahoo.com Abstract
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
Introduction Esters are a compound formed from a carboxylic acid, RCOOH, and an alcohol, R’OH [1]. 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.
Methodology
The
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