Las alquilaciones Negishi catalizadas por níquel de las aziridinas de estirenilo
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A Direct, Regioselective and Atom-Economical Synthesis of 3-Aroyl-N-hydroxy-5-nitroindoles by Cycloaddition of 4-Nitronitrosobenzene with Alkynones
Published on: January 21, 2020
Chung-Yang Huang1, Abigail G Doyle
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA.
Journal of the American Chemical Society
|March 15, 2012
Resumen
Una nueva reacción catalizada por níquel permite la síntesis de aminas sustituidas por beta a partir de N-sulfonilo aziridinas y reactivos organozinc. Este método ofrece condiciones suaves y una alta tolerancia del grupo funcional para una síntesis eficiente de aminas.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis de la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- Las reacciones de acoplamiento cruzado son vitales para la formación de enlaces C-C.
- La catálisis de níquel ofrece una alternativa rentable a los catalizadores de metales preciosos.
- Las aziridinas son versátiles heterociclos de tres miembros para la síntesis orgánica.
Objetivo del estudio:
- Para desarrollar una nueva reacción de acoplamiento cruzado catalizada por níquel.
- Para sintetizar aminas sustituidas por beta regioselectivamente.
- Para investigar el mecanismo de reacción y la estereoselectividad.
Principales métodos:
- Acoplamiento cruzado catalizado por níquel de N-sulfonilo aziridinas con reactivos organozinc.
- Utilizó una fuente de Ni (II) barata y un ligando de fumarato de dimetilo.
- Exploró condiciones de reacción leves y tolerantes al grupo funcional.
Principales resultados:
- Logró la síntesis regioselectiva de aminas sustituidas por beta.
- Demostró la eficiencia del sistema catalítico de níquel/dimetilfumarato.
- Se observó una vía de reacción estereoconvergente guiada por el grupo sulfonamida.
Conclusiones:
- Se estableció un método robusto y eficiente catalizado por níquel para la síntesis de aminas sustituidas por beta.
- La reacción se produce en condiciones suaves, tolerando varios grupos funcionales.
- El resultado estereoquímico está dictado por un mecanismo que involucra la formación de enlaces C-C dirigidos por sulfamida.
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