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Diseño, síntesis y reactividad de 1-hidrazinodienos para su uso en síntesis orgánica

Glenn M Sammis¹, Eric M Flamme, Hao Xie

¹Department of Chemistry, Princeton University, Princeton, New Jersey 08544-1009, USA.

Journal of the American Chemical Society

|June 16, 2005

Resumen

Un nuevo 1-hidrazinodieno permite las reacciones de Diels-Alder catalizadas por el ácido de Lewis. Esta estrategia sintética produce complejos derivados de ciclohexeno y decalina a través de un intermediario diazeno y un desplazamiento sigmatrópico.

Área de la Ciencia:

Química orgánica es la química orgánica.
Química sintética de la química sintética.

Sus antecedentes:

Las reacciones de Diels-Alder son cruciales para la formación de anillos de seis miembros.
El desarrollo de nuevas dienas puede ampliar el alcance de las cicloadiciones de Diels-Alder.
La síntesis estereoselectiva de moléculas policíclicas complejas sigue siendo un desafío.

Objetivo del estudio:

Introducir un nuevo 1-hidrazinodieno como un bloque de construcción versátil.
Para explorar su aplicación en el ácido de Lewis catalizó las reacciones intermoleculares Diels-Alder.
Demostrar una nueva ruta sintética para los complejos estereocímicos de los ciclohexenos y derivados de la decalina.

Principales métodos:

Síntesis de un nuevo 1-hidrazinodieno.
El ácido de Lewis catalizó las reacciones intermoleculares de Diels-Alder con alquenos con déficit de electrones.
Desprotección y eliminación para formar un intermediario diazeno.
Cambio superficial 1,5-sigmatrópico para la formación de ciclohexeno.

Principales resultados:

El nuevo 1-hidrazinodieno participó con éxito en las reacciones de Diels-Alder.
Una secuencia fácil de desprotección y eliminación generó un intermediario de diazeno.
El intermedio se sometió a una reorganización sigmatrópica espontánea para producir complejos ciclohexenos.
La metodología se aplicó para sintetizar un complejo derivado de la decalina.

Conclusiones:

Se ha desarrollado un nuevo y eficiente método sintético para los ciclohexenos complejos.
El 1-hidrazinodieno sirve como un valioso sintón para las cicloadiciones estereoselectivas.
Este enfoque ofrece una nueva vía para las intrincadas estructuras policíclicas.

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