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Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
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Síntesis de alcoholes y éteres alilicos Z- o E-Trisubstituidos por metástasis cruzada controlada cinéticamente con un
Chaofan Xu1, Zhenxing Liu1, Sebastian Torker1
1Department of Chemistry, Merkert Chemistry Center, Boston College , Chestnut Hill, Massachusetts 02467, United States.
Journal of the American Chemical Society
|October 26, 2017
Resumen
Este estudio introduce las primeras reacciones de metástasis cruzada controladas cinéticamente para crear alquenos Z- o E-trisubstituidos. Utilizando un catalizador de rutenio, este método produce eficientemente alcoholes y éteres alelicos de alta pureza estereoisomérica.
Área de la Ciencia:
- Química orgánica
- Catálisis
- Síntesis estereoselectiva
Sus antecedentes:
- Las reacciones de metástasis cruzada son cruciales para la síntesis de alquenos.
- El control de la estereoquímica en la formación de alceno trisubstituido sigue siendo un desafío.
Objetivo del estudio:
- Desarrollar las primeras reacciones de metástasis cruzada controladas cinéticamente para alquenos Z o E-trisubstituidos.
- Para lograr altos rendimientos y pureza estereoisomérica en la síntesis de alcoholes y éteres alílicos.
Principales métodos:
- Se utilizó un complejo de catecotiolato de rutenio (Ru) como catalizador (≤ 6,0 mol %).
- Se emplean condiciones controladas cinéticamente para la metástasis cruzada.
- Se han realizado estudios DFT (Teoría Funcional de la Densidad) para obtener conocimientos mecanicistas.
Principales resultados:
- Se ha logrado la síntesis de alquenos Z o E-trisubstituidos.
- Se obtienen alcoholes y éteres alilicos trisubstituidos con un rendimiento de hasta el 81%.
- Se ha demostrado una alta pureza estereoisomérica (> 98%).
- Muestra una amplia gama de sustratos, incluidas las olefinas con alcohol, aldehído, epóxido, ácido carboxílico o grupos alquenílicos.
Conclusiones:
- El método desarrollado proporciona una ruta novedosa para los alquenos trisubstituidos estereodefinidos.
- El sistema catalítico ofrece eficiencia y amplia aplicabilidad en la síntesis orgánica.
- La comprensión mecanicista apoya el control estereoquímico observado y la eficiencia de la reacción.
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