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Una estrategia de hidrosilación-oxidación de alquinos para la instalación selectiva de la funcionalidad de oxígeno
Barry M Trost1, Zachary T Ball, Kai M Laemmerhold
1Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA. bmtrost@stanford.edu
Journal of the American Chemical Society
|July 14, 2005
Resumen
Este estudio introduce un nuevo método sintético que utiliza alquinas con hidroxilo para crear cetonas y cetonas alfa-hidroxi. El proceso utiliza intermediarios de vinilsilano para la síntesis estereoselectiva, incluido un objetivo alcaloide.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Metodología sintética de la metodología sintética.
- La catálisis es la catálisis.
Sus antecedentes:
- Las alquinas con hidroxilo son versátiles bloques de construcción en la síntesis orgánica.
- El desarrollo de métodos eficientes para la síntesis de cetonas y alfa-hidroxicetonas es crucial.
- Las transformaciones estereoselectivas son clave para la síntesis de moléculas complejas.
Objetivo del estudio:
- Desarrollar una nueva ruta sintética para las cetonas y las alfa-hidroxicetonas a partir de alquinas hidroxilo-portadoras.
- Para explorar la utilidad de los intermediarios de vinilsilano generados a través de la hidrosilación.
- Demostrar la aplicación de esta metodología en la síntesis de productos naturales.
Principales métodos:
- Hidrosilación regioselectiva de alquinas catalizadas por [Cp*Ru(MeCN) 3PF6 para formar vinilsilanos.
- Oxidación de vinilsilanos lineales y cíclicos.
- Epoxidación diastereoselectiva de los vinilsilanos cíclicos.
Principales resultados:
- Las alquinas con hidroxilo fueron convertidas con éxito en cetonas o alfa-hidroxicetonas.
- Los intermediarios de vinilsilano se generaron de manera eficiente y se utilizaron en las posteriores transformaciones oxidativas.
- Se lograron equivalentes estereoselectivos de aldol, homo-aldol y bishomo-aldol.
- El método se aplicó a una síntesis concisa del alcaloide de piperidina espectalina.
Conclusiones:
- El método desarrollado proporciona una poderosa nueva estrategia para sintetizar valiosos compuestos oxigenados.
- Este enfoque ofrece una vía estereoselectiva para arquitecturas moleculares complejas.
- La aplicación a la espectalina pone de relieve la utilidad práctica de esta estrategia sintética.
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