| Autor: |
Rasool Babaahmadi, Rebecca L. Melen, Sanjukta Pahar, Lukas Gierlichs, Brian F. Yates, Alireza Ariafard, Ayan Dasgupta |
| Jazyk: |
angličtina |
| Rok vydání: |
2022 |
| Předmět: |
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| ISSN: |
1615-4150 |
| Popis: |
Decomposition of donor-acceptor diazo compounds leads to the formation of reactive carbene intermediates. These can undergo a wide variety of carbene transfer reactions to yield synthetically useful products. Herein, we report a selective borane catalyzed cyclization reaction from the combination of two different diazo compounds to afford N-substituted pyrazoles. The selective decomposition of the more reactive α-aryl α-diazoester and subsequent reaction with a vinyl diazoacetate produces N-alkylated pyrazoles in a regioselective manner. Catalytic amounts of tris(pentafluorophenyl)borane (10 mol%) were employed to afford the pyrazole products (36 examples) in yields from 59 to 80%. Extensive DFT studies have been undertaken to interpret the mechanism for this reaction which was found to go through two tandem catalytic cycles, both catalyzed by B(C6F5)3. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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