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Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
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Fragmentación mediada por Zn de oxalatos alquilo terciarios que permite la formación de centros de carbono
Yang Ye1, Haifeng Chen1, Jonathan L Sessler1
1School of Materials Science and Engineering, Center for Supramolecular Chemistry and Catalysis and Department of Chemistry , Shanghai University , Shanghai , China 200444.
Journal of the American Chemical Society
|December 21, 2018
Resumen
La reducción mediada por zinc de los oxalatos de dialquilo fragmenta eficientemente los enlaces C-O, formando radicales de alquilo. Estos radicales son atrapados para crear centros cuaternarios de carbono, útiles en la síntesis orgánica.
Área de la Ciencia:
- Química orgánica
- Química sintética
Sus antecedentes:
- La escisión del enlace carbono-oxígeno es crucial para sintetizar moléculas orgánicas complejas.
- Los alcoholes terciarios son precursores comunes, pero su activación de enlaces CO puede ser un desafío.
Objetivo del estudio:
- Desarrollar un método eficiente para la fragmentación de enlaces C-O en dialquilo-oxalatos derivados de alcoholes terciarios.
- Para utilizar los radicales alquilo generados para la construcción de centros cuaternarios de carbono.
Principales métodos:
- Utilizando la reducción mediada por zinc de los oxalatos de dialquilo.
- Utilizando cloruro de magnesio (MgCl2) como aditivo y níquel (Ni) como promotor.
- Captura de radicales alquilo con alquenos activados y productos intermedios de aril-níquel.
Principales resultados:
- Se ha demostrado una fragmentación eficiente del enlace C-O de los oxalatos de dialquilo.
- Se generaron con éxito radicales alquilo en las condiciones de reacción.
- Logró la formación de centros cuaternarios alquilados y arilados de todo el carbono.
Conclusiones:
- El método desarrollado proporciona una vía eficaz para la escisión de enlaces C-O y la generación de radicales alquilo.
- Esta estrategia permite la síntesis de valiosos centros cuaternarios de todo el carbono.
- El uso de oxalatos de dialquilo fácilmente disponibles hace que este enfoque sea sintéticamente práctico.
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