La activación reversible del enlace C-C permite el estereocontrol en las cicloadiciones carbonilativas catalizadas por Rh de aminociclopropanatos
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Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy
Published on: November 9, 2019
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Megan H Shaw1, Niall G McCreanor, William G Whittingham
1School of Chemistry, University of Bristol , Bristol, BS8 1TS, United Kingdom.
Journal of the American Chemical Society
|December 25, 2014
Resumen
Los ciclopropanos sustituidos por aminoácidos forman complejos N-heterociclos a través de la cicloadición carbonilativa catalizada por el rodio. Esta reacción ofrece una nueva estrategia de estereocontrol para la síntesis de moléculas complejas.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Química sintética de la química sintética.
Sus antecedentes:
- Las reacciones catalizadas por el rodio (Rh) son cruciales en la síntesis orgánica.
- Las cicloadiciones carbonilativas ofrecen rutas eficientes a los compuestos heterocíclicos.
Objetivo del estudio:
- Para investigar la cicloadición carbonilativa de los ciclopropanos sustituidos por aminoácidos utilizando sistemas de catalizador Rh (I).
- Explorar el mecanismo y los resultados estereoquímicos de estas reacciones.
- Desarrollar una nueva estrategia de estereocontrol para la síntesis de andamios N-heterocíclicos.
Principales métodos:
- Se utilizaron sistemas de catalizadores neutros y catiónicos de Rh (I).
- Se emplean ciclopropanos sustituidos por aminoácidos con alquenos atados.
- Investigar los mecanismos de reacción a través de estudios sintéticos y mecanicistas.
- Se analizaron los resultados estereoquímicos y la diastereoselectividad.
Principales resultados:
- Sintetizó con éxito andamios N-heterocíclicos complejos estereoquímicamente.
- Se identificó la inserción regioselectiva de Rh y CO en enlaces C-C, formando los intermediarios de la rodcyclopentanona.
- Se demostró que la formación de rodiciclopentanona es reversible con los sistemas catiónicos de Rh (I).
- Mostró altos niveles de estereocontrol influenciado por sustitutos de alqueno.
Conclusiones:
- Desarrolló una nueva cicloadición carbonilativa catalizada por rodio para la síntesis N-heterocíclica.
- Se estableció una vía dinámica de formación de rodcyclopentanona que permite el control estereoquímico.
- Destacó el potencial de esta metodología como estrategia de estereocontrolamiento en la catálisis.
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