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Alquilación selectiva de C-H de arenas complejas por una secuencia de alquilación reductora de tiantrenación de arilo
Beatrice Lansbergen1, Paola Granatino1, Tobias Ritter1
1Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm Platz 1, D-45470 Mülheim an der Ruhr, Germany.
Journal of the American Chemical Society
|May 24, 2021
Resumen
Desarrollamos un nuevo método de alquilación C-H en dos pasos para arenas complejas. Este enfoque permite la funcionalización selectiva en etapa tardía, creando diversas arenas alquiladas anteriormente inaccesibles.
Área de la Ciencia:
- Química orgánica
- Química sintética
- Catálisis
Sus antecedentes:
- La funcionalidad de las arenas en etapa tardía es crucial para el descubrimiento de fármacos y la ciencia de los materiales.
- Los métodos existentes a menudo carecen de selectividad o requieren sustratos prefuncionalizados.
- El desarrollo de estrategias eficientes y selectivas de activación de C-H sigue siendo un desafío clave.
Objetivo del estudio:
- Presentar una nueva alquilación para-selectiva de dos pasos C-H de arenas complejas.
- Permitir la funcionalización en etapas tardías con una alta selectividad y diversidad.
- Demostrar la viabilidad y solidez del método desarrollado.
Principales métodos:
- Tiantrenación de C-H selectiva en el sitio de las arenas.
- El acoplamiento cruzado reductor electrofilo catalizado por paladio.
- Utilizando reactivos basados en tiantenio para el acoplamiento de fragmentos.
Principales resultados:
- Se ha logrado la alquilación para-selectiva no dirigida de C-H de arenas complejas.
- Obtuvo acceso a una amplia gama de arenas alquiladas sintéticamente útiles.
- Demostró la robustez de la transformación a través del acoplamiento de fragmentos complejos.
Conclusiones:
- El método presentado ofrece una vía práctica y selectiva para la funcionalización en etapas tardías.
- Esta estrategia de alquilación C-H expande la caja de herramientas sintéticas para acceder a arquitecturas moleculares complejas.
- El enfoque basado en el tiantreno es prometedor para el acoplamiento de fragmentos complejos.
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