The Skraup synthesis is a chemical reaction used to synthesize quinolines. Aniline is heated with sulfuric acid, an oxidizing agent, and glycerol to yield quinoline.

In this example, nitrobenzene is both the solvent and the oxidizing agent.

Reaction mechanism

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

References

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1. Skraup, Z. H. Ber. 1880, 13, 2086.
2. Manske, R. H. F. Chem. Rev. 1942, 30, 115. (Review)
3. Manske, R. H. F.; Kulka, M. Org. React. 1953, 7, 80-99. (Review)
4. Wahren, M. Tetrahedron 1964, 20, 2773. (Review)

See also

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• Bischler-Napieralski reaction
• Doebner-Miller reaction

Organic reactions