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Metátesis de apertura de anillo / reordenamiento de oxicopa: una nueva estrategia para la síntesis de compuestos que
Brian H White1, Marc L Snapper
1Eugene F. Merkert Chemistry Center, Boston College, Chestnut Hill, MA 02467, USA.
Journal of the American Chemical Society
|December 4, 2003
Resumen
La metátesis de apertura y cierre de anillos crea dienes clave para el reordenamiento de oxy-Cope. Este método sintetiza estereoselectivamente sistemas bicíclicos de anillo medio, aunque el sistema de biciclo[7,3,0]dodecano produce isómeros mixtos.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química sintética de la química sintética.
Sus antecedentes:
- Las reacciones de metástasis son cruciales para la formación de enlaces carbono-carbono.
- Los reordenamientos de Oxy-Cope permiten la síntesis de sistemas complejos de anillos.
Objetivo del estudio:
- Para desarrollar una síntesis estereoselectiva de 1,5-bis-dienes.
- Para utilizar estos dienes en reorganizaciones de oxy-Cope aceleradas por aniones para sistemas cíclicos.
Principales métodos:
- Metátesis de apertura y cierre de anillos en sustratos de ciclobuteno.
- Empleando sustratos con funcionalidad de oxígeno angular.
- Reorganización de oxicopio acelerado por aniones.
Principales resultados:
- Introducción estereospecífica de los 1,5-bis-dienes. también en el estereo.
- Preparación controlada por estéreo de sistemas de bicicletas de anillo medio.
- Formación de isómeros olefinos mixtos en el sistema de biciclo[7,3,0]dodecano.
Conclusiones:
- La secuencia de reacción descrita es efectiva para la síntesis estereocontrolada de compuestos bicíclicos.
- El paso de reordenamiento de oxy-Cope puede conducir a mezclas isoméricas dependiendo del sistema objetivo.
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