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Síntesis asimétrica catalítica de ésteres aleloicos quirales

Jeffrey S Cannon¹, Stefan F Kirsch, Larry E Overman

¹Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, California 92697-2025, USA.

Journal of the American Chemical Society

|October 15, 2010

Resumen

Un nuevo método catalítico permite la síntesis enantioselectiva de ésteres alilicos ramificados a partir de alcoholes alilicos. Este enfoque utiliza un catalizador de paladio (II) para una esterificación alilica asimétrica eficiente.

Área de la Ciencia:

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

Sus antecedentes:

Los ésteres alilicos son valiosos intermediarios sintéticos.
La síntesis enantioselectiva de ésteres alelicos ramificados sigue siendo un desafío.

Objetivo del estudio:

Desarrollar una síntesis catalítica enantioselectiva ampliamente útil de ésteres alelicos ramificados.
Para utilizar el prociral (Z) -2-alqueno-1-ols como materiales de partida.

Principales métodos:

Conversión del alcohol alílico en el intermedio tricloroacetimidato utilizando el tricloroacetonitrilo.
Enantioselectivo S(N) 2' sustitución del intermediario con ácidos carboxílicos.
La catálisis utiliza un complejo específico de paladio (II), (R) - (COP-OAc) o su enantiómero.

Principales resultados:

Desarrollo exitoso de una síntesis catalítica enantioselectiva ampliamente útil.
Demostración de la sustitución enantioselectiva limpia de S(N) 2' por varios ácidos carboxílicos.
Definir el alcance y las limitaciones de la metodología desarrollada.

Conclusiones:

El método desarrollado proporciona una ruta eficiente a los ésteres alelicos ramificados enriquecidos enantioméricamente.
Esta esterificación alilica asimétrica catalítica es una valiosa adición a la química orgánica sintética.
La metodología ofrece un enfoque práctico para acceder a los bloques de construcción de éster alelico quiral.

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