Hemetsberger indole synthesis
| Hemetsberger indole synthesis | |
|---|---|
| Named after | Helfried Hemetsberger |
| Reaction type | Ring forming reaction |
The Hemetsberger indole synthesis (also called the Hemetsberger–Knittel synthesis) is a chemical reaction that thermally decomposes a 3-aryl-2-azido-propenoic ester into an indole-2-carboxylic ester.[1][2]
Yields are typically above 70%. However, this is not a popular reaction, due to the lack of stability and difficulty in synthesizing the starting material.
Reaction mechanism
The mechanism is unknown. However, azirine[3] intermediates have been isolated. The mechanism is postulated to proceed via a nitrene intermediate.[4]
References
- S2CID 91741917.
- doi:10.1039/a909834h.
- ^ Gilchrist, T. L. (2001). "Activated 2H-Azirines as Dienophiles and Electrophiles" (PDF). Aldrichimica Acta. 34 (2): 51. Archived from the original (PDF) on 15 May 2013.
- .