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Hidroaminación migratoria: una síntesis fácil y enantioselectiva de los benzomorfanos
1Department of Chemistry, Stanford University, Stanford, California 94305-5080, USA. bmtrost@stanford.edu
Journal of the American Chemical Society
|July 17, 2003
Resumen
Desarrollamos un nuevo y eficiente método para sintetizar benzomorfanos con altos rendimientos. Esta estrategia utiliza una nueva cicloisomerización y reacciones catalizadas por paladio para la construcción de moléculas complejas.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química sintética de la química sintética.
- Química Medicinal La Química Medicinal es el campo de la Química Medicinal.
Sus antecedentes:
- Los benzomorfanos son una clase de alcaloides con un potencial farmacológico significativo.
- Las rutas sintéticas existentes a menudo carecen de eficiencia o enantioselectividad.
- El desarrollo de síntesis enantioselectivas generales y eficientes es crucial para acceder a nuevos derivados del benzomorfano.
Objetivo del estudio:
- Establecer una estrategia general y altamente eficiente para la síntesis enantioselectiva de los benzomorfanos.
- Demostrar la utilidad de nuevas metodologías sintéticas en la síntesis de moléculas complejas.
Principales métodos:
- Síntesis enantioselectiva que utiliza la alquilación alilica asimétrica (AAA) catalizada por el paladio de los enolados de cetona.
- Una nueva cicloisomerización diastereoselectiva a través de la hidroaminación migratoria.
- El rendimiento general del 45-46% se obtiene a partir de materiales de partida disponibles en el mercado.
Principales resultados:
- Síntesis enantioselectiva exitosa de benzomorfanos con alto rendimiento general.
- Demostración de una reacción de cicloisomerización diastereoselectiva sin precedentes.
- Aplicación efectiva de AAA catalizado por paladio en síntesis compleja, estableciendo tres centros estereogénicos contiguos.
Conclusiones:
- La estrategia desarrollada ofrece un enfoque poderoso y general para la síntesis enantioselectiva de benzomorfano.
- La nueva cicloisomerización y la metodología AAA tienen una amplia aplicabilidad en la síntesis de alcaloides.
- Este trabajo proporciona una base para el descubrimiento de nuevas terapias basadas en el benzomorfano.
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