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La diaminación enantioselectiva catalizada por el paladio de alquenos mediante el uso de N-fluorobenzenosulfonimida

Erica L Ingalls¹, Paul A Sibbald, Werner Kaminsky

¹Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195-1700, USA.

Journal of the American Chemical Society

|June 6, 2013

Resumen

Este estudio introduce una diaminación encinal enantioselectiva catalizada por el paladio de alquenos. Produce de manera eficiente las diaminas vicinales diferencialmente protegidas con alta enantioselectividad utilizando N-fluorobenzenesulfonimida.

Área de la Ciencia:

Química orgánica es la química orgánica.
La catálisis de la catálisis.
Síntesis asimétrica de síntesis.

Sus antecedentes:

La diaminación vicina de alquenos es una transformación crucial en la síntesis orgánica.
El desarrollo de métodos enantioselectivos para esta reacción sigue siendo un desafío significativo.
La catálisis de paladio ofrece una poderosa plataforma para la formación de enlaces C-N.

Objetivo del estudio:

Para reportar una nueva diaminación encinal enantioselectiva catalizada por el paladio de alquenos no activados.
Para utilizar N-fluorobenzenesulfonimida como oxidante y fuente de nitrógeno.
Para lograr altos rendimientos y enantioselectividades para las diaminas vicinales diferencialmente protegidas.

Principales métodos:

Reacción catalizada por el paladio enantioselectiva utilizando ligandos Ph-pybox y Ph-quinox.
Utilizando N-fluorobenzenesulfonimida como oxidante y fuente de nitrógeno.
Estudios mecanicistas que incluyen cristalografía de rayos X del complejo intermedio.

Principales resultados:

Diaminación exitosa de alquenos no activados con buenos rendimientos y altas enantioselectividades.
Formación de diaminas vicinales diferencialmente protegidas.
Conocimientos mecánicos que indican la formación selectiva de un solo producto de aminopaladación diastereomérica.

Conclusiones:

Se ha desarrollado un método nuevo, eficiente y enantioselectivo para la diaminación vicinal.
La metodología proporciona acceso a valiosos bloques de construcción de diamina vicinal quiral.
La alta enantioselectividad observada se atribuye al control estereoquímico durante el paso de aminopaladación.

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