The Synthesis Of Aspirin
catalyst, synthesizing an ester (Weldegirma, 2014). The catalyst has to be something that will provide the addition of a proton, such as a Lewis acid, in order to provide a more reactive electrophile and speed up the reaction (Fischer Esterification Fischer-Speier Esterification, 2015). Some possibilities for the catalyst are sulfuric acid, tosic acid, and phosphoric acid (James, 2014). For the experiment, the starting materials are salicylic acid, acetic anhydride, and phosphoric acid. The salicylic acid is the compound that contained the alcohol and the acetic anhydride is the compound that contained the carboxylic acid. The main purpose of the acetic anhydride is to donate the acetyl to the salicylic acid, which in the end produces acetylsalicylic acid.Experimental Section
Mix salicylic acid, 85% phosphoric acid, acetic anhydride, and a boiling stone in a conical vial. Monitor by TLC, 1:1hexane:EtOAc, followed by heating reaction in steam bath for 5 minutes. Take another TLC, add water to reaction to decompose excess acetic anhydride and cool to room temperature. Place vial in ice bath to for 10 minutes to allow crystallization, and then remove solvent using vacuum filtration on a Hirsch funnel. Dry product, weight it, conduct IR, proton NMR, and carbon NMR.
The data showed that there was a percent yield of 55%. Also, when looking at the IR spectrum on can see that it I very erratic and ridged, which makes it difficult to interpret. The state of the IR spectrum could…