Fritsch–Buttenberg–Wiechell rearrangement
| Fritsch–Buttenberg–Wiechell rearrangement | |
|---|---|
| Named after | Paul Ernst Moritz Fritsch Wilhelm Paul Buttenberg Heinrich G. Wiechell |
| Reaction type | Rearrangement reaction |
| Identifiers | |
| RSC ontology ID | RXNO:0000250 |
The Fritsch–Buttenberg–Wiechell rearrangement, named for Paul Ernst Moritz Fritsch (1859–1913), Wilhelm Paul Buttenberg, and Heinrich G. Wiechell, is a chemical reaction whereby a 1,1-diaryl-2-bromo-alkene rearranges to a 1,2-diaryl-alkyne by reaction with a strong base such as an alkoxide.[1][2][3][4]
This rearrangement is also possible with
alkyl substituents.[5]
Reaction mechanism
The strong base deprotonates the vinylic hydrogen, which after alpha elimination forms a vinyl carbene. A 1,2-aryl migration forms the 1,2-diaryl-alkyne product. The mechanism of the FBW rearrangement was a subject of on-surface studies where the vinyl radical was visualised with sub-atomic resolution.[6]
Scope
One study explored this reaction for the synthesis of novel polyynes:[7][8]
See also
References
- .
- .
- .
- .
- PMID 10814340.
- PMID 29967394.
- methyl iodide. The reaction product is a biomolecule found in for instance Bidens pilosa
- Darses, B.; Milet, A.; Philouze, C.; Greene, A. E.; Poisson, J.-F. o., Ynol Ethers from Dichloroenol Ethers: Mechanistic Elucidation Through 35Cl Labeling. Organic Letters 2008, 10 (20), 4445-4447.