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La cicloadición intra e intermolecular [5 + 2] catalizada por el rodio de 3-aciloxi-1,4-enino y alquino con migración
Xing-Zhong Shu1, Xiaoxun Li, Dongxu Shu
1School of Pharmacy, University of Wisconsin, Madison, Wisconsin 53705, United States.
Journal of the American Chemical Society
|February 28, 2012
Resumen
Una nueva reacción de cicloadición [5 + 2] catalizada por rodio sintetiza eficientemente diversos anillos de siete miembros. Este método involucra 3-aciloxi-1,4-eninas (ACE) y alquinas, que presentan una migración única de 1,2-aciloxi.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- Los anillos de siete miembros son importantes andamios en la química medicinal y la ciencia de los materiales.
- Rutas sintéticas eficientes para anillos funcionales de siete miembros siguen siendo un desafío.
- La catálisis del rodio ofrece vías únicas para la construcción de moléculas complejas.
Objetivo del estudio:
- Para desarrollar una nueva reacción de cicloadición [5 + 2] catalizada por rodio.
- Para sintetizar diversos anillos de siete miembros con una migración 1,2-aciloxi.
- Para explorar las vías de reacción intramolecular e intermolecular.
Principales métodos:
- Se utilizan catalizadores de rodio, incluidos los complejos catiónicos y neutros.
- Empleó 3-aciloxi-1,4-eninas (ACE) como el componente de cinco carbonos y alquinas como el componente de dos carbonos.
- Investigó el efecto de los ligandos de fosfito y fosfina pobres en electrones en la eficiencia de la reacción.
Principales resultados:
- Se desarrolló con éxito una reacción de cicloadición [5 + 2] catalizada por rodio.
- Logró una síntesis eficiente de anillos de siete miembros a través de vías intramoleculares e intermoleculares.
- Demostró la versatilidad de la reacción con varios ACE y alquinas.
- Se observó una migración de 1,2-aciloxi acompañando la formación de anillos.
- Productos generados con tres dobles enlaces susceptibles a la funcionalización selectiva.
Conclusiones:
- Estableció una nueva y eficiente cicloadición catalizada por rodio [5 + 2] para la síntesis de anillos de siete miembros.
- La reacción procede con una migración 1,2-aciloxi única, que ofrece acceso a estructuras complejas.
- La metodología desarrollada proporciona una plataforma versátil para la construcción de anillos funcionales de siete miembros con aplicaciones potenciales en diversos campos químicos.
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