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Síntesis estereoselectiva de ciclohexanos mediante una estrategia de anulación catalizada por iridio (5 + 1)
Wasim M Akhtar1, Roly J Armstrong1, James R Frost1
1Department of Chemistry, Chemical Research Laboratory , University of Oxford , Oxford , OX1 3TA , United Kingdom.
Journal of the American Chemical Society
|September 14, 2018
Resumen
Este estudio introduce una síntesis catalizada por iridio de ciclohexanos funcionalizados utilizando cetonas de metilo y 1,5-diolos. El nuevo método emplea el préstamo secuencial de hidrógeno para la construcción estereoselectiva de compuestos cíclicos multisubstituidos.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Metodología sintética
Sus antecedentes:
- Los derivados del ciclohexano son frecuentes en los productos farmacéuticos y naturales.
- La síntesis eficiente y estereoselectiva de ciclohexanos sustituidos sigue siendo un desafío.
Objetivo del estudio:
- Desarrollar un nuevo método catalizado por iridio para sintetizar ciclohexanos funcionalizados.
- Establecer una estrategia estereoselectiva (5 + 1) para la construcción de núcleos de ciclohexano.
Principales métodos:
- Utilizó un catalizador de iridio para la reacción.
- Se emplean reacciones secuenciales de préstamo de hidrógeno.
- Las cetonas de metilo reaccionadas con 1,5-diol.
Principales resultados:
- Se ha logrado un acceso directo a productos cíclicos multisubstituidos.
- Se ha demostrado un alto nivel de control estéreo en la síntesis.
- Se han sintetizado con éxito ciclohexanos funcionalizados.
Conclusiones:
- El método desarrollado catalizado por iridio ofrece una nueva ruta para los ciclohexanos funcionalizados.
- La estrategia de préstamo secuencial de hidrógeno permite la construcción estereoselectiva del núcleo de ciclohexano.
- Esta metodología proporciona una herramienta poderosa para acceder a moléculas cíclicas complejas.
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