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Published on: January 3, 2018
Sustitución directa de las aminas alilicas primarias por sales de sulfinato
Xue-Song Wu1, Yan Chen, Man-Bo Li
1Joint Laboratory of Green Synthetic Chemistry, Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.
Journal of the American Chemical Society
|August 30, 2012
Resumen
Este estudio introduce una nueva reacción catalizada por el paladio para crear sulfonos alílicos a partir de aminas alílicas primarias y sales de sulfinato. El método ofrece un excelente control sobre la regionalidad y la estereoselectividad, dando como resultado productos diversos y ópticamente puros.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- Las sulfonas alilicas son valiosos intermediarios sintéticos.
- La funcionalización directa de las aminas alilicas sigue siendo un desafío.
- Los métodos existentes para la síntesis asimétrica de sulfones alilicos asimétricos tienen limitaciones en el alcance del sustrato.
Objetivo del estudio:
- Desarrollar un nuevo método catalítico para la síntesis directa de sulfonas alilicos.
- Para lograr una alta regioselectividad y estereoselectividad en la sustitución de aminas alilicas primarias.
- Ampliar el alcance del sustrato para la síntesis asimétrica de sulfonas alilicas quirales.
Principales métodos:
- Sustitución directa catalizada por paladio del grupo NH (((2) en aminas alilicas primarias con sales de sulfinato.
- Se utilizó el catalizador [Pd(allilo) Cl](2) con el ligando 1,4-bis(difenilfosfino) butano (dppb) para la sustitución α-selectiva.
- Empleado 1,1'-bi-2-naftol (BINOL) ligando para la síntesis asimétrica con aminas quirales.
Principales resultados:
- Se ha logrado una excelente regioselectividad y estereoselectividad en la formación de sulfonas alílicas.
- Sintetizó estructuralmente diversas sulfonas alilicas en buenos a excelentes rendimientos con exclusiva selectividad E.
- Se obtienen sulfonas alilicas quirales con alta pureza óptica y excelente retención del exceso enantiomérico (ee) de aminas alilicas no simétricas.
Conclusiones:
- El sistema catalítico desarrollado proporciona una ruta eficiente a los sulfonos alilicos alfa ramificados y quirales.
- Este método complementa las estrategias asimétricas existentes al permitir el uso de electrófilos alilicos asimétricos.
- La reacción ofrece una herramienta valiosa para la construcción de moléculas complejas con un alto control estereoquímico.
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01:28Preparation of 1° Amines: Gabriel Synthesis
Direct alkylation is not a suitable method for synthesizing amines because it produces polyalkylated products. Gabriel synthesis is the most preferred method to exclusively make primary amines. The method uses phthalimide, which contains a protected form of nitrogen that participates in alkylation only once to predominantly give primary amines.
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