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Inducción asimétrica remota con vinilketeno silil n,o-acetal

Shin-Ichi Shirokawa¹, Masato Kamiyama, Tomoaki Nakamura

¹Faculty of Pharmaceutical Sciences, Tokyo University of Science (RIKADAI), 2641 Yamazaki, Nodashi, Chiba 278-8510, Japan.

Journal of the American Chemical Society

|October 21, 2004

Resumen

Una nueva reacción de aldol Mukaiyama ofrece un control preciso sobre la estereoquímica. Este método crea eficientemente estructuras moleculares complejas que se encuentran en productos naturales.

Área de la Ciencia:

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

Sus antecedentes:

La reacción de Mukaiyama aldol es una reacción fundamental de formación de enlaces carbono-carbono.
El control de la estereoquímica en la síntesis de moléculas complejas, particularmente en policetidas, sigue siendo un desafío significativo.

Objetivo del estudio:

Para desarrollar una reacción de aldol Mukaiyama vinílogous altamente regio y diastereoselectiva.
Establecer un método para controlar la inducción asimétrica remota en la síntesis orgánica.

Principales métodos:

Se utilizó un vinilketeno quiral silyl N,O-acetal.
Se emplea tetracloruro de titanio (TiCl4) como catalizador del ácido de Lewis.

Principales resultados:

Se lograron altos niveles de regio- y diastereoselectividad en la reacción viníloga Mukaiyama aldol.
Demostró la importancia de un grupo alfa-metilo para una alta estereoselectividad.
Desarrolló un método de un solo paso para construir una unidad delta-hidroxi-alfa, gamma-dimetil-alfa, beta-carbonilo insaturado.

Conclusiones:

La metodología desarrollada proporciona una ruta efectiva para la síntesis asimétrica.
Esta reacción es valiosa para la construcción de los principales motivos estructurales presentes en los productos naturales de policetida.

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