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Síntesis asimétrica catalítica de ferroceno y las bisfosfinas P-esterógenas
Cédric Genet1, Steven J Canipa, Peter O'Brien
1Department of Chemistry, University of York, Heslington, York YO10 5DD, UK.
Journal of the American Chemical Society
|July 20, 2006
Resumen
Este estudio demuestra la síntesis asimétrica catalítica de los ferrocenos quirales planos y las fosfinas P-esterogénicas utilizando reactivos de organolitio y cantidades subtoiquiométricas de sparteina o su sustituto.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Síntesis asimétrica de síntesis.
- La catálisis por catálisis.
Sus antecedentes:
- Los ligandos quirales son cruciales para los procesos asimétricos catalizados por metales.
- Los ferrocenos quirales planos y las fosfinas P-estero-génicas son importantes clases de ligandos.
- La síntesis eficiente de estos ligandos es altamente deseable.
Objetivo del estudio:
- Desarrollar un método de síntesis asimétrico catalítico para los ferrocenos quirales planos y las fosfinas P-esterogénicas.
- Para utilizar reactivos de organolitio fácilmente disponibles y auxiliares quirales.
Principales métodos:
- El uso de n-butilitio (n-BuLi) o sec-butilitio (s-BuLi).
- Utilizando cantidades subtoiquiométricas (0,1-0,5 equivalentes) de (-) -sparteína o un sustituto de (+) -sparteína.
- Implementación de estrategias de síntesis asimétrica catalítica.
Principales resultados:
- Síntesis asimétrica catalítica exitosa de los ferrocenos quirales planos.
- Síntesis asimétrica catalítica exitosa de fosfinas y bisfosfinas P-esterógenas.
- Eficacia demostrada de los auxiliares de aminas quirales subtoiquiométricas.
Conclusiones:
- La sparteína substoiquiométrica o su sustituto permite una síntesis catalítica asimétrica eficiente.
- Este método proporciona acceso a valiosos ligandos quirales para la catálisis asimétrica.
- El enfoque es aplicable tanto al ferroceno como a los ligandos quirales basados en la fosfina.
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