This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Joe Julian CH:221:12 Tuesday, 1-4 PM September 14, 2004 Synthesis of Aspirin from Salicylic Acid 2 Abstract Aspirin (acetylsalicylic acid) is a derivative of salicylic acid with the same medicinal values but fewer side effects. It is used widely as a pain killer and anti-inflammatory. In this experiment, aspirin was synthesized from salicylic acid and acetic anhydride. To determine the product’s purity, the melting point of aspirin was then measured using a Thomas-Hoover Uni- Melt device. The product had a low percent yield and was found to be impure due to its low melting point. Introduction The active ingredient in willow bark, salicylic acid, is known to have medicinal values for alleviating pain, fever, and swelling 1 . Unfortunately, salicylic acid can have potentially serious side effects in certain people 1 . Some of these side effects include stomach ulcers and salicylism, which is aspirin poisoning 2 . Fortunately, a safer derivative of aspirin was discovered by a German chemist named Felix Hoffman 1 . He synthesized acetylsalicylic acid, which is the acetyl derivative of salicylic acid 1 . This aspirin derivative greatly reduced, but not entirely eliminated, the side effects of salicylic acid. In this experiment, acetylsalicylic acid was synthesized from the acidification of salicylic acid and acetic anhydride (see Figure 1). The objective was to convert a specific amount of salicylic acid into the same amount of aspirin that was high in purity. The amount of each compound should be the same because there is a 1:1 ratio between them (see Equation 1). The purity of the synthesized aspirin was measured by determining its melting point. Soluble impurities increase the range over which a compound melts and often decreases its overall melting point temperature 4 . If the experiment went as expected, a pure sample of aspirin with a high percent yield would have been obtained. high percent yield would have been obtained....
View Full Document
- Spring '07
- Salicylic acid