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Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
Published on: July 28, 2022
Diastereo- y enantioselección controlada en una aziridinación asimétrica catalítica
Aman A Desai1, William D Wulff
1Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, USA.
Journal of the American Chemical Society
|September 3, 2010
Resumen
Los catalizadores de ácido Brønsted de poliborato quiral permiten una aziridinación asimétrica. Este estudio demuestra su uso con diazoacetamidas para producir trans-aziridinas, expandiendo el protocolo universal catalítico asimétrico de aziridinación.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Catalización asimétrica por catálisis asimétrica.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- El poliborato quiral y los ácidos de Brønsted derivados de los ligandos VANOL y VAPOL son catalizadores establecidos para la síntesis de cis-aziridinas.
- Estos catalizadores median la reacción entre las diarilmetiliminas y los diazoesters.
Objetivo del estudio:
- Para investigar la actividad catalítica de los ácidos de Brønsted poliborato quiral con diazoacetamidas.
- Desarrollar un protocolo universal de aziridinación catalítica asimétrica para las aziridinas cis y trans.
Principales métodos:
- Utilizando catalizadores de ácido Brønsted de poliborato quiral preparados a partir de los ligandos VANOL y VAPOL.
- Reaccionando las diarilmetiliminas con las diazoacetamidas para formar las trans-aziridinas.
- Analizar el alcance del sustrato incluyendo aldehídos aromáticos y alifáticos.
Principales resultados:
- El catalizador de poliborato quiral media con éxito la formación de trans-aziridinas a partir de iminas y diazoacetamidas con una alta inducción asimétrica.
- La reacción exhibe un amplio alcance de sustrato, que acomoda varios aldehídos aromáticos y alifáticos.
- La selectividad de la cara es independiente del compuesto diazo, con catalizadores (S) -VANOL/(S) -VAPOL que dirigen la adición a la cara Si para las cis-aziridinas y la cara Re para las trans-aziridinas.
Conclusiones:
- Se ha establecido un protocolo universal catalítico asimétrico de aziridinación, que se adapta tanto a los diazoésteres como a las diazoacetamidas.
- El método desarrollado proporciona un alto control estereoquímico para la síntesis de cis- y trans-aziridinas.
- Este trabajo amplía la utilidad sintética de los catalizadores de ácido de Brønsted poliborato quiral en síntesis asimétrica.
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