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Ciclizaciones biomiméticas de 2-Imino-Nazarov a través de la aziridinación de enealeno
Joshua R Corbin1, Devin R Ketelboeter1, Israel Fernández2
1Department of Chemistry, University of Wisconsin, 1101 University Avenue, Madison, Wisconsin 53706, United States.
Journal of the American Chemical Society
|March 7, 2020
Resumen
Los investigadores desarrollaron un nuevo método utilizando metilenaziridinas bicíclicas para crear cationes amidoalilo para sintetizar carbociclos complejos que contienen aminas a través de ciclizaciones de Nazarov.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Metodología sintética
Sus antecedentes:
- Los cationes amidoalilo son valiosos sintetones de tres carbonos para la construcción de carbociclos que contienen aminas.
- Los métodos existentes para la generación y utilización de cationes amidoalilo son limitados.
- Los cationes oxalilo han sido estudiados más extensamente que los cationes amidoalilo.
Objetivo del estudio:
- Desarrollar un método nuevo y eficiente para la generación de cationes amidoalilo.
- Explorar la utilidad de estos intermedios en las ciclizaciones de Nazarov.
- Proporcionar un enfoque bioinspirado y impulsado por la tensión para la síntesis de carbociclos.
Principales métodos:
- Apertura de anillo por tensión bioinspirada de las metilenaziridinas cíclicas.
- Generación de cationes intermedios de 2-amidopentadienilo.
- Las reacciones de ciclización de Nazarov.
- Catalización del complejo Rh2 (transferencia de nitreno y promoción del ácido de Lewis).
- Estudios experimentales y computacionales.
Principales resultados:
- Generación exitosa de los intermediarios del catión 2-amidopentadienilo.
- Estos intermedios se someten fácilmente a las ciclizaciones de Nazarov.
- El método ofrece ventajas sobre la química de cationes 3-pentadienilo existente, incluida la facilidad de generación y la reactividad mejorada.
- Se logró el control del posicionamiento de los alquenos y el potencial de alta diastereoselectividad (dr).
- Los productos pueden ser elaborados en aminociclopentanos completamente sustituidos.
- Se identificó una doble función para el complejo Rh2 (L) 4.
Conclusiones:
- Se ha establecido una nueva estrategia bioinspirada para sintetizar carbociclos que contienen aminas.
- El método desarrollado proporciona una plataforma versátil para acceder a arquitecturas moleculares complejas.
- La comprensión del papel catalítico del complejo Rh2 (L) 4 facilita el desarrollo futuro de variantes asimétricas.
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