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Transformaciones estereospecíficas de ésteres alquilborónicos habilitadas por la transmetalización directa de boro a
1Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, United States.
Journal of the American Chemical Society
|May 1, 2023
Resumen
Los ésteres organoborónicos quirales se transforman eficientemente en reactivos organozincos quirales estables a través de la transmitación estereorretente. Estos reactivos permiten reacciones estereospecíficas de difluorocarbeno, acoplamientos cruzados y trifluorometilación.
Área de la Ciencia:
- Química orgánica
- Química organometálica
- Estereoquímica
Sus antecedentes:
- Los ésteres organobóricos secundarios quirales son valiosos intermedios sintéticos.
- El desarrollo de métodos para su funcionalización estereoselectiva es crucial.
Objetivo del estudio:
- Desarrollar un método estereoretente para la síntesis de reactivos quirales orgánicos secundarios.
- Para explorar la utilidad sintética de estos nuevos compuestos organozinc.
Principales métodos:
- Activación de los ésteres organobóricos secundarios quirales con el tert-butilitio.
- Transmetación estereorretente con acetato de zinc o cloruro de zinc.
- Reacciones posteriores de los reactivos organozinc con electrófilos y en reacciones de acoplamiento cruzado.
Principales resultados:
- Síntesis eficiente de reactivos quirales secundarios de alquilzinco de configuración estable.
- Se han demostrado reacciones estereospecíficas con el difluorocarbeno.
- Aplicación exitosa en el acoplamiento cruzado catalizado por el paladio y la trifluorometilación mediada por el cobre.
- Los estudios mecánicos y computacionales aclararon el proceso de transmitación.
Conclusiones:
- La transmisión estereorretente de ésteres organobóricos proporciona una ruta confiable hacia los reactivos quirales organozinc.
- Estos compuestos organozinc son versátiles bloques de construcción para la síntesis asimétrica.
- La metodología desarrollada amplía el conjunto de herramientas para crear moléculas quirales complejas.
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