Lab: Synthesis of Aspirin & Oil of Wintergreen
In 1897, Felix Hoffman, a chemist working in Elberfeld, Germany, in a laboratory owned by Friedrich Bayer, formulated a pure and stable form of acetylsalicylic acid. Hoffman was motivated by the suffering of his father, who had severe arthritis, and could not tolerate salicylic acid, a medicine prevalent at that time. Hoffman and Bayer gave it the name “A-spirin”, which appears to have come from acetylation and spirin, part of the name for Meadow-sweet (Spiraea ulmaria), a plant rich in salicylates.
Bayer patented the name and commenced to market the product in 1899. It was a huge success and sales grew rapidly. In fact, the company set up by Friedrich Bayer & Company is generally reckoned to have been the first pharmaceutical company, and the production of aspirin is generally accepted to have laid the foundation of the modern pharmaceutical industry.
Some notable dates:
400 BCSalicylates recommended by Hippocrates
Pre-industrial Europe Salicylate-rich plants used in folk medicine
1763Rev. Edward Stone describes the medicinal uses of salicylates
1859Salicylic acid is synthesized from carbolic acid
1897Hoffman produces acetylsalicylic acid
1899Friedrich Bayer & Company market Aspirin
Purpose: To synthesize aspirin and to determine the percent yield of the amount that was made.
Salicylic acidAcetic anhydrideAcetylsalicylic acid
Materials and Equipment:
3 g salicylic acid
4 mL acetic anhydride
5 mL methyl alcohol
Concentrated H2SO4 (droppers)
Ice and ice bath
Large watch glass or Petri dish
500-mL and (2) 50-mL beakers
10-mL, 50-mL and 100-mL graduated cylinders
125-mL Erlenmeyer flask
Large test tube
Ring stand and large ring
Buchner funnel and sidearm flask
Hotplate and thermometer
Scoopula and tweezers
The acetic anhydride and sulfuric acid can cause bad burns and thus will be used in the hood. If they come in contact with your skin, immediately wash the area with copious amounts of water.