Photo by C Lloyd at SSERC (Public Domain)
Aspirin is an analgesic (pain-killing), anti-inﬂammatory and anti-pyretic (fever-reducing) drug. It is an ester and can be prepared by the condensation reaction between 2-hydroxybenzoic acid (or salicylic acid) and ethanoic anhydride:
After purification by recrystallisation, the product can be weighed and the percentage yield determined. The purity of the ﬁnal sample can be checked by determining its melting point.
Preparation of aspirin – pupil guide
Preparation of aspirin – Teacher’s guide
Preparation of aspirin – Risk assessment