Bischler-Möhlau indole synthesis
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The Bischler-Möhlau indole synthesis is a chemical reaction that forms a 2-aryl-indole from a α-bromo-acetophenone and excess aniline.
[edit] Reaction mechanism
For a reaction with such simple starting materials, the reaction mechanism is surprisingly complex. The first two step involve the reaction of the α-bromo-acetophenone with molecules of aniline to form intermediate 4. The charged aniline forms a decent enough leaving group for an electrophilic cyclization to form intermediate 5, which quickly aromatizes and tautomerizes to give the desired indole 7.
[edit] References
- Bischler, A. et al.; Ber. 1892, 25, 2860.
- Bischler, A. et al.; Ber. 1893, 26, 1336.
- Möhlau, R.; Ber. 1881, 14, 171.
- Möhlau, R.; Ber. 1882, 15, 2480.
- Fischer, E.; Schmitt, T.; Ber. 1888, 21, 1071.
- Weygand, F.; Richter, E. Ber. 1955, 88, 499.
- LeRoi-Nelson, K.; Seefeld, R. L. J. Am. Chem. Soc. 1958, 80, 5957.
