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Las adiciones fotociclointermoleculares [2+2] enantioselectivas de isoquinolona mediadas por una plantilla quiral de

Susannah C Coote¹, Thorsten Bach

¹Lehrstuhl für Organische Chemie I and Catalysis Research Center, Technische Universität München , Lichtenbergstrasse 4, 85747 Garching, Germany.

Journal of the American Chemical Society

|October 2, 2013

Resumen

Los investigadores desarrollaron las primeras adiciones fotociclointermoleculares [2+2] enantioselectivas de isoquinolona y alquenos. Este método utiliza una plantilla quiral de enlace de hidrógeno para lograr altos rendimientos y selectividades para los productos de ciclobutano.

Área de la Ciencia:

Química orgánica es la química orgánica.
La fotoquímica es la fotoquímica.
Química supramolecular de las moléculas.

Sus antecedentes:

La síntesis enantioselectiva es crucial para los productos farmacéuticos y los materiales.
Las adiciones fotocicloofrecen vías únicas a estructuras cíclicas complejas.
El control de la estereoquímica en las fotocicloadiciones intermoleculares sigue siendo un desafío.

Objetivo del estudio:

Para reportar la primera fotocicloadición [2+2] intermolecular enantioselectiva de isoquinolona con alceno.
Desarrollar un método para crear productos funcionalizados de ciclobutano con alto control estéreo.
Para investigar el uso de plantillas quirales de enlace de hidrógeno en reacciones de fotocicloadición.

Principales métodos:

Se emplearon fotorreacciones a baja temperatura.
Se utilizó una plantilla quiral de enlace de hidrógeno para formar complejos supramoleculares.
La isoquinolona y varios alquenos se utilizaron como sustratos.

Principales resultados:

Se lograron excelentes rendimientos (86-98%) de productos funcionalizados de ciclobutanos.
Se observó una destacada regio-, diastereoselectividad y enantioselectividad (88-99% ee).
La plantilla quiral protegía efectivamente una cara del sustrato de la isoquinolona.

Conclusiones:

Este estudio presenta un método novedoso y altamente efectivo para la fotocicloadición intermolecular [2+2] enantioselectiva.
La estrategia desarrollada proporciona acceso a valiosos derivados de ciclobutano con un preciso control estereoquímico.
Las plantillas quirales de enlace de hidrógeno son potentes herramientas para la fotocatálisis asimétrica.

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