As derivatives of carboxylic acids, esters are abundant compounds that often contribute to the fragrances in flowers, fruits, and coffee. Esters are synthesized from either organic or inorganic acids through a process called esterification. In this reaction, a carboxylic acid (RCOOH) and an alcohol (R’OH) mix in the presence of a strong acid catalyst to form a neutral, water-insoluble ester (RCOO’R) that gives off a pleasant smell. The following is an example of this reaction: The reaction above represents the formation of 3-methylbutyl ethanoate from ethanoic acid, 3-methylbutanol, and an acid catalyst.
Reaction Scheme: Table of Reagents, Products, and Byproducts:
Compound MW (g/mol) Density (g/mL) BP (℃) MP
(℃) Experimental …show more content…
The aqueous layer was removed again and placed into a beaker for later disposal. The saturated aqueous sodium chloride was added to the remaining organic layer in the increment of about 1 mL. The aqueous layer formed during this process was disposed once again. The organic layer was transferred into a clean and tared vial. About 5 spheres of anhydrous calcium chloride were added to the liquid and the mixture were swirled. The flask was corked and let sit for few minutes while the calcium chloride absorbed the water. The process was repeated till the cloudy layer was no longer formed after. The contents of the vial were decanted into a pre-weighed 5 mL round bottom flask and massed to determine the crude yield of the product. The contents of the vial was distilled at a collection rate of 1 drop per 20 to 30 seconds. The lower-boiling impurities were collected before and within 5 Celsius degrees of the boiling point of the product, 3-methylbutyl acetate. The esters were collected at the boiling point of 142℃. When the collecting process was done, the apparatus was removed from the heat. The odors of obtained ester and hood partner’s ester were examined. The percent yield of crude and distilled product were calculated.
A sample of the product was placed into an infrared spectrometer to generate a visual representation of energy bands given off by the compound that signify functional groups in the product. The appearance of certain bands helps to identify the composition of the compound present. To clean up, all wastes were disposed in the Organic Liquid Waste container in the hood. The sand bath was turned off, equipment put away, drawer locked, workspace cleaned up, fume hood closed, and the TA’s signature was obtained before leaving the