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Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units

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Una cascada de expansión de anillos arilativos de ciclobutenos fusionados a través de intermediarios de corta vida

Norihito Arichi¹, Ken-ichi Yamada¹, Yousuke Yamaoka¹

¹Graduate School of Pharmaceutical Sciences, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501, Japan.

Journal of the American Chemical Society

|July 21, 2015

Resumen

Una nueva cascada de expansión de anillos arilativos sintetiza carbociclos de tamaño mediano a partir de ciclobutenos fusionados. Este proceso implica un intermediario de cicloalcadino transitorio, confirmado por experimentos de transferencia de quiralidad.

Área de la Ciencia:

Química orgánica
Química sintética

Sus antecedentes:

Los carbociclos de tamaño medio son motivos estructurales importantes en productos naturales y farmacéuticos.
Las rutas sintéticas eficientes para los carbociclos de tamaño medio siguen siendo un desafío en la síntesis orgánica.

Objetivo del estudio:

Desarrollar una nueva metodología sintética para la construcción de carbociclos de tamaño medio.
Para investigar el mecanismo de la cascada de expansión del anillo arilativo.

Principales métodos:

Apertura térmica del anillo electrocíclico 4π de los ciclobutenes fundidos.
Reacción en cascada arilativa.
Experimentos de transferencia de quiralidad para la detección de reacciones intermedias.

Principales resultados:

Síntesis exitosa de carbociclos de tamaño mediano a partir de ciclobutenos fundidos.
Demostración de una cascada de expansión de anillos arilativos.
Pruebas para la generación transitoria de un intermediario cis, trans-cicloalcadieno.

Conclusiones:

La cascada de expansión de anillos arilativos desarrollada proporciona una ruta eficiente a los carbociclos de tamaño medio.
La reacción se produce a través de un intermediario de cicloalcadieno generado térmicamente.
La transferencia de quiralidad confirma el carácter transitorio del intermediario propuesto.

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