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Síntesis enantioselectiva de los [6]carbohelicenos

Elisa González-Fernández¹, Leo D M Nicholls¹, Lukas D Schaaf¹

¹Institut für Organische und Biomolekulare Chemie, Georg-August-Universität Göttingen , Tammannstraße 2, 37077 Göttingen, Germany.

Journal of the American Chemical Society

|January 24, 2017

Resumen

Los investigadores desarrollaron un nuevo método para sintetizar carbohelicenos sustituidos [6] utilizando ligandos de fosfonita derivados de TADDOL. Este enfoque permite una síntesis altamente regioselectiva y enantioselectiva a través de reacciones catalizadas por oro.

Área de la Ciencia:

Química orgánica
Síntesis asimétrica
Catálisis

Sus antecedentes:

Los carbohelicenos son hidrocarburos aromáticos policíclicos complejos con propiedades estructurales y electrónicas únicas.
El desarrollo de rutas sintéticas eficientes y selectivas para los carbohelicenos sustituidos sigue siendo un desafío en la química orgánica.

Objetivo del estudio:

Desarrollar un método nuevo y altamente selectivo para la síntesis de carbohelicenos sustituidos [6].
Para explorar la utilidad de los ligandos de fosfonita α-catiónica derivados de TADDOL en la catálisis asimétrica.

Principales métodos:

Hidroariación intramolecular secuencial catalizada por oro de las diinas.
Se utilizan ligandos modulares de fosfonita α-catiónica derivados de TADDOL como ligandos auxiliares para la catálisis del oro.

Principales resultados:

Logró una síntesis altamente regio y enantioselectiva de carbohelicenos sustituidos [6].
Se demostró la eficacia de los ligandos de fosfonita derivados de TADDOL en el control de la selectividad.
La naturaleza modular de los ligandos y su capacidad para mejorar la reactividad del centro de oro fueron clave para el éxito.

Conclusiones:

Los fosfonitos α-catiónicos derivados de TADDOL son ligandos auxiliares efectivos para la catálisis asimétrica del oro.
Esta metodología proporciona una herramienta poderosa para acceder a los carbohelicenos complejos sustituidos [6] con un alto control estereoquímico.

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