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Sustitución nucleofílica en los estereocentros cuaternarios de carbono

Veeranjaneyulu Lanke¹, Ilan Marek¹

¹Schulich Faculty of Chemistry, Technion - Israel Institute of Technology, Technion City 3200009, Haifa, Israel.

Journal of the American Chemical Society

|March 7, 2020

Resumen

Los derivados del ciclopropil carbinol se transforman eficientemente en compuestos acíclicos mediante la sustitución nucleofílica. Este proceso produce diastereómeros individuales con alta regioselectividad y estereoselectividad, ofreciendo una nueva ruta sintética.

Área de la Ciencia:

Química orgánica
Síntesis estereoselectiva
Mecanismos de reacción

Sus antecedentes:

Los derivados del ciclopropilcarbinol son productos intermedios sintéticos muy valiosos.
El control de la regioselectividad y la estereoselectividad en las reacciones de sustitución nucleofílica es un desafío persistente.

Objetivo del estudio:

Investigar la sustitución nucleofílica regio y estereoselectiva de los derivados del ciclopropilcarbinol.
Desarrollar un método eficaz para la preparación de compuestos acíclicos enriquecidos enantioméricamente.

Principales métodos:

Utilizando como materiales de partida los derivados del ciclopropilcarbinol.
Empleando reacciones de sustitución nucleofílicas dirigidas al centro de carbono cuaternario.
Pasos de reacción catalítica de las alquinas disponibles en el mercado.

Principales resultados:

Se ha conseguido una sustitución nucleofílica regio- y estereoselectiva en el carbono cuaternario.
Se ha demostrado la inversión pura de la configuración, dando como resultado un solo diastereómero.
Se han sintetizado con éxito haluros y ésteres terciarios diastereoméricamente puros y enriquecidos enantioméricamente.

Conclusiones:

La selectividad observada se atribuye a un intermediario de ciclobutonio propuesto.
Este método facilita el acceso a productos acíclicos valiosos en un número limitado de pasos.
Permite la preparación de diversos compuestos acíclicos funcionalizados a partir de precursores simples.

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