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Anulación [3+3] catalizada por oro de las iminas de azometina con ésteres de propargilo
Nathan D Shapiro1, Yun Shi, F Dean Toste
1Department of Chemistry, University of California, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|August 4, 2009
Resumen
Una nueva reacción catalizada por oro sintetiza eficientemente tetrahidropiridazinas sustituidas a partir de precursores simples. Este método ofrece una vía rápida a diversos compuestos heterocíclicos a través de un intermediario oro-carbenoide propuesto.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Química Heterocíclica La Química Heterocíclica es una de las más conocidas.
Sus antecedentes:
- Las reacciones de cicloadición son fundamentales en la síntesis orgánica para la construcción de moléculas cíclicas.
- La catálisis del oro ha surgido como una poderosa herramienta para activar enlaces insaturados y facilitar nuevas transformaciones.
- Las tetrahidropiridazinas sustituidas son importantes andamios en la química medicinal y la ciencia de los materiales.
Objetivo del estudio:
- Para desarrollar una nueva reacción de [3+3]-cicloadición catalizada por oro.
- Para sintetizar una amplia gama de derivados sustituidos de tetrahidropiridazina.
- Para dilucidar el mecanismo de reacción.
Principales métodos:
- Utilizando catalizadores de oro para la reacción de cicloadición.
- Utilizando ésteres de propargilo y iminas de azometina como materiales de partida.
- Caracterización de los productos de tetrahidropiridazina resultantes.
Principales resultados:
- Desarrollo exitoso de la reacción de cicloadición [3+3] catalizada por oro.
- Síntesis rápida de varios derivados sustituidos de la tetrahidropiridazina.
- Evidencia que apoya un mecanismo escalonado que involucra un intermediario oro-carbenoide y adición de 1,3 dipolos.
Conclusiones:
- La reacción catalizada por oro desarrollada proporciona una ruta eficiente a las tetrahidropiridazinas sustituidas.
- La reacción ofrece un método versátil para acceder a estructuras heterocíclicas complejas a partir de materiales de partida simples.
- Un mecanismo propuesto que involucra intermediarios de carbenoides de oro mejora la comprensión de la vía de reacción.
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