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Adición asimétrica conjugada de reactivos organoboron a las enonas comunes utilizando catalizadores de cobre
Chunlin Wu1, Guizhou Yue2, Christian Duc-Trieu Nielsen1
1Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University , 21 Nanyang Link, Singapore 637371.
Journal of the American Chemical Society
|January 13, 2016
Resumen
Los complejos de cobre catalizan reacciones de adición asimétricas. Se descubrió un nuevo mecanismo de inserción de 1,4 que involucra productos intermedios de arilcobre (I), que difiere de las vías tradicionales.
Área de la Ciencia:
- Química organometálica
- Catálisis asimétrica
- Síntesis orgánica
Sus antecedentes:
- Las enonas acíclicas son intermedios sintéticos versátiles.
- La catálisis asimétrica es crucial para producir compuestos enantioméricamente puros.
- Las reacciones catalizadas por cobre ofrecen rutas sintéticas eficientes.
Objetivo del estudio:
- Investigar la actividad catalítica de los complejos de cobre-fosforamidita.
- Elucidar el mecanismo de la adición asimétrica de arilborón a las enonas.
- Identificar nuevas vías de reacción en la química del cobre orgánico.
Principales métodos:
- Catalización asimétrica mediante el uso de complejos de cobre-fosforamidita.
- Reacción de los reactivos de arilborón con las enonas acíclicas.
- Estudios mecanicistas, incluida la identificación intermedia.
Principales resultados:
- Se logró una adición asimétrica eficiente de reactivos de arilborón a las enonas acíclicas.
- Se observó una rara inserción de especies de arilcobre (I).
- Los enolados de cobre unidos a O se formaron directamente a través de esta nueva vía.
Conclusiones:
- Los complejos de cobre-fosforamidita son catalizadores efectivos para la adición asimétrica de arilborón.
- Un nuevo mecanismo de inserción de 1,4, distinto de las vías clásicas, opera en estas reacciones.
- Este descubrimiento proporciona nuevos conocimientos mecanicistas sobre la reactividad del organocobre con las enonas.
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