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

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Alquilaminación enantioselectiva de alquenos no activados bajo catálisis de cobre

Zibo Bai¹, Heng Zhang¹, Hao Wang¹

¹State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China.

Journal of the American Chemical Society

|December 30, 2020

Resumen

Una nueva reacción catalizada por cobre permite la adición de grupos alquilo enantioselectivos a los alquenos. Este método sintetiza eficientemente β-lactamas quirales con dos estereocentros, cruciales para el desarrollo de fármacos.

Área de la Ciencia:

Química orgánica
Catálisis
Síntesis asimétrica

Sus antecedentes:

El desarrollo de métodos enantioselectivos para crear moléculas orgánicas complejas es crucial en la química medicinal.
Los alquenos internos no activados son sustratos desafiantes para la funcionalización directa.

Objetivo del estudio:

Desarrollar un nuevo método de alquilación enantioselectiva para alquenos internos no activados.
Para sintetizar β-lactamas quirales con un alto control estereoquímico.

Principales métodos:

Catalización del cobre utilizando un grupo directivo de aminoquinolina ligado a la amida.
El uso de ésteres de 4-alquilo Hantzsch como donantes de radicales de alquilo.
Utilizando un óxido de biarilo difosfina como un ligando quiral.

Principales resultados:

Adición enantioselectiva exitosa de varios grupos alquilo a los alquenos internos.
Alto rendimiento y excelente enantioselectividad en la síntesis de β-lactamas.
Formación de dos estereocentros contiguos en Cβ y el β-sustituto.

Conclusiones:

El método desarrollado proporciona un acceso eficiente a los valiosos β-lactamas quirales.
Los estudios mecanicistas identificaron la adición de radicales alquilo a un alqueno coordinado por Cu (II) como el paso enantioselectivo.

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