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Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium Under Mild Reaction Conditions
Published on: March 20, 2014
Acoplamiento deshidrogenativo cruzado asimétrico habilitado por el diseño y la aplicación de ácidos fósforicos
Andrew J Neel1, Jörg P Hehn, Pascal F Tripet
1Department of Chemistry, University of California , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|September 13, 2013
Resumen
Los investigadores desarrollaron una nueva reacción enantioselectiva de formación de enlaces C-N utilizando aniones quirales de fosfato. Este método crea eficientemente aminas cíclicas a partir de 1,2,3,4-tetrahidroisoquinolina, ofreciendo un nuevo enfoque catalítico.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Síntesis asimétrica de síntesis.
Sus antecedentes:
- La síntesis enantioselectiva de aminas cíclicas es crucial para los productos farmacéuticos.
- Los métodos convencionales para mejorar la enantioselectividad en la catálisis del ácido fosfórico derivado de BINOL a menudo se basan en el aumento de la masa estérica.
- El desarrollo de nuevos sistemas catalíticos es esencial para la formación eficiente de enlaces C-N.
Objetivo del estudio:
- Desarrollar una nueva reacción enantioselectiva formadora de enlaces C-N para la síntesis de aminoácidos cíclicos derivados de 1,2,3,4-tetrahidroisoquinolina.
- Diseñar y utilizar aniones quirales de fosfato como catalizadores para esta transformación.
- Explorar el uso de las interacciones de enlace de hidrógeno para mejorar la enantioselectividad.
Principales métodos:
- Desarrollo de una biblioteca de ácidos fosfóricos derivados del 3,3'-triazolyl BINOL.
- Formación catalítica asimétrica de enlaces C-N utilizando los ácidos fosfóricos diseñados.
- Optimización de las condiciones de reacción para maximizar el rendimiento y la enantioselectividad.
Principales resultados:
- Desarrollo exitoso de una reacción formadora de enlaces C-N enantioselectiva.
- Síntesis eficiente de aminoácidos cíclicos derivados de la 1,2,3,4-tetrahidroisoquinolina.
- Demostración de las interacciones de enlace de hidrógeno que juegan un papel clave en el logro de una alta enantioselectividad.
Conclusiones:
- La catálisis de aniones quirales de fosfato desarrollada ofrece una alternativa efectiva para la formación de enlaces C-N enantioselectivos.
- Este enfoque proporciona una nueva estrategia para controlar la enantioselectividad, yendo más allá de simplemente aumentar el volumen estérico del catalizador.
- Los hallazgos abren nuevas vías para la síntesis de aminos cíclicos quirales con potenciales aplicaciones farmacéuticas.
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