When people suffer from muscular pain, headaches, and fevers they more often than not turn to over the counter medicines. But which one do they use? Does one work better than the other? What side effects do each contain? Is one better for you? Aspirin and acetaminophen are the most widely used, commercially available, pharmaceutical drugs.1 Canadians turn to these of non-prescription remedies to ease minor aches and pains, irritations and illnesses without having any clear knowledge of which drug will alleviate their symptoms. This essay will focus on the synthesis of aspirin and acetaminophen, how they work, and the side effects and benefits of using them.
Aspirin is a member of the chemical family salicylates. It is one of the best known aromatic acetates. The most important compound in the synthesis of aspirin is salicylic acid. It is created from phenol by a process discovered by a German chemist, Hermann Kolbe.
This process is called The Kolbe Synthesis.2 Sodium phenoxide is heated with CO2 under pressure. The product of this reaction is then acidified to produce salicylic acid.
From there, salicylic acid under goes esterfication. Esterification is the acid-catalyzed reaction of a carboxyl group (-COOH) and an -OH group of either an alcohol or phenol to form a carboyxlate ester. In the synthesis of aspirin, the -OH group is the phenolic -OH group attached to ring of the salicylic acid. The acetyl group, -COCH3 comes form acetic anhydride. The reaction is catalyzed by phosphoric acid. The result is acetylsalicylic acid, a weaker acid than salicylic acid.3 The acetyl group effectively masks the acidity of the drug during its ingestion. After it goes into the small intestine, it is turned back to salicylic acid where it can enter the bloodstream and perform its pain-relieving action.4 In acetaminophen,