Skraup reaction

The Skraup synthesis is a chemical reaction used to synthesize quinolines. It is named after the Czech chemist Zdenko Hans Skraup (1850-1910). In the archetypal Skraup, aniline is heated with sulfuric acid, glycerol, and an oxidizing agent to yield quinoline.



In this example, nitrobenzene serves as both the solvent and the oxidizing agent. The reaction, which otherwise has a reputation for being violent, is typically conducted in the presence of ferrous sulfate.

Reaction mechanism
The mechanism is unclear, yet there is good reason to believe that acrolein (obtained by dehydration of glycerol) is an intermediate.