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Conversión enantiodivergente de los alcoholes secundarios quirales en alcoholes terciarios
Jake L Stymiest1, Viktor Bagutski, Rosalind M French
1School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
Nature
|December 17, 2008
Resumen
La síntesis de moléculas quirales con centros estereogénicos cuaternarios es un reto. Este nuevo método de dos pasos convierte de manera eficiente los alcoholes secundarios en los alcoholes terciarios deseados con un alto control estéreo.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La estereoquímica es la estereoquímica.
- Síntesis asimétrica de síntesis.
Sus antecedentes:
- Las moléculas quirales existen como formas de imagen especular (enantiómeros) con distintas actividades biológicas.
- La síntesis selectiva de enantiómeros individuales es crucial en la química y la medicina.
- La creación de moléculas con centros estereogénicos cuaternarios, particularmente alcoholes terciarios, sigue siendo un desafío sintético significativo.
Objetivo del estudio:
- Desarrollar un método general y altamente selectivo para sintetizar alcoholes terciarios con centros estereogénicos cuaternarios.
- Proporcionar una solución para un desafío de larga data en la síntesis asimétrica.
Principales métodos:
- Una secuencia sintética de dos pasos que comienza con los alcoholes secundarios quirales fácilmente disponibles.
- Conversión del grupo hidroxilo del alcohol secundario y el hidrógeno adyacente a un centro estereogénico cuaternario mediante la introducción de grupos alquilo, alquenilo o arilo.
- Utilizando ésteres borónicos terciarios intermedios para una posible funcionalización adicional.
Principales resultados:
- Logró una síntesis eficiente y altamente estereoselectiva de alcoholes terciarios a partir de alcoholes secundarios.
- Demostró la capacidad de producir cualquiera de los enantiómeros del alcohol terciario con alto estereocontrol.
- Estableció una solución general para acceder a los centros estereogénicos quaternales quirales.
Conclusiones:
- La metodología presentada ofrece una ruta versátil y eficaz a una amplia gama de alcoholes terciarios quirales.
- Este enfoque supera un obstáculo importante en la síntesis estereoselectiva.
- Se espera que el método desarrollado tenga amplias aplicaciones en síntesis orgánica y descubrimiento de fármacos.
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