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Síntesis total de (+) -ileabetoxazol a través de una carbociclización Pauson-Khand [2 + 2 + 1] mediada por el hierro
David R Williams1, Akshay A Shah
1Department of Chemistry, Indiana University , Bloomington, Indiana 47405, United States.
Journal of the American Chemical Society
|May 24, 2014
Resumen
Los investigadores lograron la síntesis total de (+) -ileabetoxazol utilizando el acoplamiento de Stille y la carbociclado mediado por hierro. Este estudio presenta nuevos métodos para construir moléculas complejas que contienen oxazol y sus núcleos aromáticos.
Área de la Ciencia:
- Síntesis orgánica La síntesis orgánica.
- Química Medicinal La Química Medicinal es el campo de la Química Medicinal.
- Química Heterocíclica La Química Heterocíclica es una de las más conocidas.
Sus antecedentes:
- (+) -Ileabetoxazol es un producto natural complejo con actividad biológica potencial.
- Las rutas sintéticas eficientes para los oxazoles sustituidos son valiosas para el descubrimiento de fármacos.
- Las síntesis anteriores pueden carecer de pasos clave o control regioquímico.
Objetivo del estudio:
- Desarrollar una nueva y eficiente síntesis total de (+) -ileabetoxazol.
- Explorar nuevas metodologías para la construcción de alenos 1,1-disubstituidos y ciclopentenonas.
- Para investigar la funcionalización regioselectiva de los heterociclos de oxazol.
Principales métodos:
- Acoplamiento cruzado silencioso de estananos propargílicos con 5-iodo-1,3-oxazoles para formar alenos.
- Carbociclización [2+2+1] mediada por hierro para la síntesis de ciclopentenona.
- Reacciones de inserción de paladio para la sustitución de heterociclos regiocontrolada.
- Reducciones asimétricas de hidruro de cobre.
Principales resultados:
- El éxito de la síntesis total de (+) -ileabetoxazol (1).
- Generación de alenos 1,1-disubstituidos (11) a través del acoplamiento Stille.
- Formación de un nuevo intermediario de ciclopentenona.
- Se han demostrado sustituciones regioselectivas catalizadas por paladio en el anillo de oxazol.
Conclusiones:
- La estrategia sintética desarrollada proporciona una ruta eficiente hacia el (+) -ileabetoxazol.
- El estudio destaca la utilidad del acoplamiento de Stille y la carbociclización mediada por hierro en la síntesis de moléculas complejas.
- Se establecieron nuevos métodos para la funcionalización del oxazol y la construcción del anillo aromático.
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