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Published on: March 20, 2017
La activación de los enlaces C(sp3) -C(sp3) y C(sp3) -H de 1,1-ciclopentano disubstituido
Chisato Mukai1, Yuu Ohta, Yuki Oura
1Division of Pharmaceutical Sciences, Graduate School of Medical Sciences, Kanazawa University, Kakuma-machi, Kanazawa 920-1192, Japan. mukai@p.kanazawa-u.ac.jp
Journal of the American Chemical Society
|November 14, 2012
Resumen
Este estudio demuestra una escisión sin precedentes de los enlaces C(sp(3)) -C(sp(3)) en el ciclopentano no activado utilizando catálisis con rodio. Se sintetizaron nuevos compuestos bicíclicos y espirocíclicos a través de nuevas reacciones de cicloadición.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis es la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- C(sp(3)) -C(sp(3)) la escisión de enlaces es un desafío, especialmente en los alcanos cíclicos no activados.
- La catálisis de Rhodium (I) ofrece potencial para nuevas activaciones y transformaciones de enlaces.
Objetivo del estudio:
- Para lograr una escisión sin precedentes de los enlaces C(sp(3)) -C(sp(3)) del ciclopentano no activado.
- Desarrollar nuevas rutas sintéticas para complejas estructuras policíclicas.
Principales métodos:
- Cícloadición catalizada por el rodio (I) de todos los alquinos de ciclociclopentano.
- Generación in situ de rhodabicyclo[4.3.0]nona-1,6-diene intermedios. en el mismo lugar.
- [7+2] cicloadición a través de la eliminación de β-C.
- La activación selectiva del enlace Cγ-H en el sitio mediante la alteración del catalizador Rh (I).
Principales resultados:
- Escisión exitosa de los enlaces no activados de ciclopentano C (((sp (((3)) -C (((sp ((3)).
- Formación de derivados de biciclo[7.4.0]tridecatrieno en buenos rendimientos.
- Síntesis de nuevos esqueletos de espiro[2.4]heptano a través de la activación selectiva del sitio Cγ-H.
Conclusiones:
- La catálisis del rodio permite una escisión sin precedentes de los enlaces C (sp) -C (sp) en el ciclopentano.
- Se ha establecido una nueva estrategia sintética para esqueletos de biciclo[7.4.0]tridecatrieno y espiro[2.4]heptano.
- La modificación del catalizador permite la activación selectiva del sitio C-H, expandiendo la utilidad sintética.
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