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Adición de conjugados alquinos enantioselectivos habilitados por ligandos P,N atropisoméricos fácilmente sintonizados
Sourabh Mishra1, Ji Liu1, Aaron Aponick1
1Center for Heterocyclic Compounds, Department of Chemistry, University of Florida , Gainesville, Florida 32611, United States.
Journal of the American Chemical Society
|February 17, 2017
Resumen
Un nuevo ligando heterocíclico biarílico quiral, Me-StackPhos, permite la alquinización conjugada enantioselectiva catalizada por cobre de los aceptores ácidos de Meldrum. Este método sintetiza eficientemente bloques de construcción quirales valiosos, incluido un agente preclínico.
Área de la Ciencia:
- Química orgánica
- Catálisis asimétrica
- Química medicinal
Sus antecedentes:
- Los ligandos P,N tradicionales de 6 miembros presentan limitaciones en la selectividad y la reactividad de afinación.
- Los andamios heterocíclicos biarílicos quirales de 5 miembros ofrecen una alternativa prometedora para la evolución del ligando.
- El desarrollo de métodos eficientes para la síntesis de bloques quirales es crucial para el descubrimiento de fármacos.
Objetivo del estudio:
- Informar sobre una nueva reacción de alquinización de conjugado enantioselectivo catalizado por cobre utilizando un nuevo ligando heterocíclico biarílico quiral de 5 miembros.
- Demostrar la utilidad de esta reacción en la síntesis de valiosos bloques de construcción de ácido quiral β-alquinilo de Meldrum.
- Mostrar la aplicación de esta metodología en la síntesis de un agente preclínico.
Principales métodos:
- Utilizó un ligando heterocíclico quiral de 5 miembros, Me-StackPhos, en reacciones catalizadas por cobre.
- Se realizó una alquinización conjugada enantioselectiva de los aceptores ácidos de Meldrum con varios alquinos.
- Se emplean principios de catálisis asimétrica para lograr una alta enantioselectividad.
Principales resultados:
- El ligando Me-StackPhos desarrollado facilitó altos rendimientos y una excelente enantioselectividad en la alquinilación conjugada.
- La reacción demostró un amplio alcance del sustrato, tolerando una amplia gama de socios de acoplamiento de alquinos.
- Con éxito sintetizado bloques de construcción de ácido quiral β-alkynyl Meldrum con una alta eficiencia.
Conclusiones:
- El nuevo ligando Me-StackPhos representa un avance significativo en el diseño de ligandos para catálisis asimétrica.
- La alquinización cu-catalizada reportada ofrece una vía versátil y eficiente a valiosos intermediarios quirales.
- Esta metodología permite la síntesis simplificada de moléculas complejas, incluidos los agentes farmacéuticos como OPC 51803.
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