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Catálisis asimétrica de las reacciones de hetero-eno con complejos tridentados de Schiff con base de cromo (III)

Rebecca T Ruck¹, Eric N Jacobsen

¹Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA.

Journal of the American Chemical Society

|March 21, 2002

Resumen

Un nuevo complejo de cromo (III) cataliza eficientemente las reacciones asimétricas de hetero-enos. Este catalizador produce altos rendimientos de éteres beta-hidroxyenol con una excelente enantioselectividad, avanzando la síntesis quiral.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
Catalización asimétrica por catálisis asimétrica.
Síntesis orgánica La síntesis orgánica.

Sus antecedentes:

Los ligandos de base de Schiff son versátiles en la coordinación de iones metálicos.
Los complejos de cromo (III) han demostrado potencial para catalizar transformaciones orgánicas.
Las reacciones asimétricas de hetero-enos son cruciales para la síntesis de moléculas quirales.

Objetivo del estudio:

Desarrollar un nuevo complejo tridentado de Schiff con base de cromo ((III) para la catálisis asimétrica.
Para investigar la actividad catalítica del complejo en la reacción hetero-ene.
Para aclarar el mecanismo del proceso catalítico.

Principales métodos:

Síntesis y caracterización de un complejo tridentado de Schiff con base de cromo (III).
Reacciones asimétricas de hetero-enos utilizando aldehídos de arilo y derivados de propeno.
Cristalografía de rayos X para el análisis estructural de un complejo de cromo relacionado.
Estudios mecanicistas que involucran desecantes químicos.

Principales resultados:

El complejo de cromo ((III) catalizó la reacción asimétrica de hetero-eno con altos rendimientos.
Se lograron excelentes enantioselectividades para los productos de éter beta-hidroxyenol.
La cristalografía de rayos X reveló una estructura dimérica puenteada con centros de seis coordenadas Cr (III).
Se propuso un mecanismo que involucra la disociación del agua facilitada por un desecante.

Conclusiones:

El complejo de cromo (III) desarrollado es un catalizador eficaz para las reacciones asimétricas de hetero-eno.
El estudio proporciona información sobre los aspectos estructurales y mecánicos del sistema catalítico.
Este trabajo contribuye al avance de la síntesis enantioselectiva de valiosos compuestos orgánicos.

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