Experiment 22 Synthesis, Purification and Analysis of an Organic Compound

Experiment 22 Synthesis, Purification and Analysis of an Organic Compound 

Background When acids react with alcohols, an ester and water is formed  

Aspirin, also known as acetylsalicylic acid (ASA), can be synthesized when the carboxyl group in acetic acid (----COOH) reacts with the (--------OH group in the salicylic acid molecule  

However, the driving force in this reaction is not large, so one usually ends up with an equilibrium mixture of water, salicylic acid, ASA and acetic acid. A better approach to produce ASA (aspirin) is to react acetic anhydride with salicylic acid in the presence of phosphoric or sulfuric acid acting as a catalyst  

Scenario A student prepared ASA starting with 2.00 g of salicylic acid and 5.00 mL of acetic anhydride (density = 1.08 g mL-1). After the product was dried, it weighed 1.90 grams. The student then hydrolyzed the ASA with sodium hydroxide and heated the mixture to produce the salicylate dianion  

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