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Eterificación propargílica enantioselectiva catalizada por el cobre de ésteres propargílicos con alcoholes

Kazunari Nakajima¹, Masashi Shibata, Yoshiaki Nishibayashi

¹Institute of Engineering Innovation, School of Engineering, The University of Tokyo , Yayoi, Bunkyo-ku, Tokyo, 113-8656, Japan.

Journal of the American Chemical Society

|February 7, 2015

Resumen

Este estudio introduce el primer método de eterificación propargílica enantioselectiva. La catálisis Copper-Pybox produce eficientemente éteres propargílicos quirales a partir de ésteres y alcoholes o fenoles con altos rendimientos y enantioselectividad.

Área de la Ciencia:

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

Sus antecedentes:

Los éteres propargílicos son valiosos intermediarios sintéticos.
El desarrollo de métodos enantioselectivos para su síntesis es crucial para acceder a las moléculas quirales.

Objetivo del estudio:

Desarrollar un nuevo método enantioselectivo para la eterificación propargílica.
Para utilizar ésteres propargílicos fácilmente disponibles y varios alcoholes/fenoles como sustratos.

Principales métodos:

Empleando una cantidad catalítica de un complejo cobre-Pybox.
Reaccionando ésteres propargílicos con alcoholes alifáticos y fenoles.

Principales resultados:

Logró buenos a altos rendimientos de éteres propargílicos.
Se obtiene una enantioselectividad de alta a excelente, de hasta el 99% ee.
Demostró la primera éterificación propargílica enantioselectiva exitosa.

Conclusiones:

El método desarrollado catalizado por cobre es efectivo para la eterificación propargílica enantioselectiva.
Esto proporciona una nueva ruta a los éteres propargílicos enriquecidos enantioméricamente.

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