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Epimerización de los centros de carbono terciario a través de la escisión radical reversible de los enlaces C3H no
Yaxin Wang1, Xiafei Hu1, Cristian A Morales-Rivera2
1State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry , Nankai University , Tianjin 300071 , China.
Journal of the American Chemical Society
|July 10, 2018
Resumen
Este estudio introduce un nuevo método para la edición estereoquímica a través de la escisión reversible de enlaces terciarios C-H no activados. El nuevo protocolo utiliza un reactivo de yodo hipervalente para la epimerización eficiente de andamios de carbono desafiantes.
Área de la Ciencia:
- Química orgánica
- Estereoquímica
- Metodología sintética
Sus antecedentes:
- La epimerización es crucial para modificar la estereoquímica en los compuestos orgánicos.
- Los métodos existentes se dirigen principalmente a los enlaces ácidos C ((sp3) -H, lo que hace que los enlaces terciarios C-H no activados sean un desafío.
- El desarrollo de métodos para la epimerización de enlaces C-H terciarios no activados es sintéticamente importante.
Objetivo del estudio:
- Desarrollar un protocolo práctico para la epimerización de carbonos terciarios con enlaces C ((sp3) -H no activados.
- Para permitir la edición estereoquímica de andamios de carbono complejos.
- Para superar las limitaciones de los métodos de epimerización existentes.
Principales métodos:
- Utilizó un reactivo de yodo hipervalente, el benziodoxole azida.
- H2O empleado en condiciones de reacción suaves.
- Se ha investigado la escisión de radicales reversibles de enlaces C ((sp3) -H no activados.
Principales resultados:
- Logró el primer protocolo sintéticamente útil para la epimerización de carbonos terciarios a través de la escisión de enlaces C ((sp3) -H no activados.
- Se ha demostrado una excelente reactividad y selectividad para enlaces 3°C-H no activados en varios cicloalcanos.
- Proporcionó una poderosa estrategia para editar la estereoquímica en andamios de carbono previamente intratables.
Conclusiones:
- El método desarrollado ofrece un nuevo enfoque para el control estereoquímico en la síntesis orgánica.
- El papel catalítico único del N3• como transporte del átomo de hidrógeno es clave para la eficiencia y la selectividad de la reacción.
- Este trabajo amplía el conjunto de herramientas para manipular arquitecturas moleculares complejas.
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