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Synthesis of Hypervalent Iodonium Alkynyl Triflates for the Application of Generating Cyanocarbenes
Published on: September 8, 2013
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Parámetros de nucleofilicidad de los ílidos de yodo estabilizados para caracterizar su potencial sintético
Saloua Chelli1, Konstantin Troshin1, Peter Mayer1
1Department Chemie, Ludwig-Maximilians-Universität München , Butenandtstrasse 5-13, 81377 München, Germany.
Journal of the American Chemical Society
|July 19, 2016
Resumen
Este estudio investiga la reacción de los ylidos de yodo con los iones de carbenio e iminio. Estos ylidos muestran nucleophilicidad única, demostrando ser efectivos en las reacciones de ciclopropanación activadas por iminio.
Área de la Ciencia:
- Química orgánica
- Mecanismos de reacción
- Catálisis asimétrica
Sus antecedentes:
- Los ylidos de yodo sustituidos por β-dicarbonilo son nucleófilos nuevos.
- Comprender su reactividad con iones electrófilos es crucial para las aplicaciones sintéticas.
Objetivo del estudio:
- Investigar la cinética y los mecanismos de las reacciones de yeloide de yodo con iones de carbenio e iminio.
- Determinar la nucleofilicidad de estos ylidos y su idoneidad para reacciones activadas por iminio.
- Para demostrar la utilidad de los ylidos de yodo en la ciclopropanación asimétrica.
Principales métodos:
- Estudios cinéticos con constantes de velocidad de segundo orden (k2).
- Análisis de la relación de energía libre lineal (log k = sN(N + E)).
- Ciclopropanación asimétrica con el catalizador de MacMillan.
Principales resultados:
- Las reacciones proceden a través del ataque nucleofílico determinante de la ylide.
- Los ylidos de yodo exhiben nucleofilicidad comparable a las pirrolas e indoles.
- Se logró una ciclopropanación asimétrica exitosa de cinnamaldehyde.
Conclusiones:
- Los ylidos de yodo son nucleófilos versátiles adecuados para las transformaciones activadas por iminio.
- La metodología desarrollada permite una ciclopropanación asimétrica eficiente.
- Este trabajo amplía el alcance de los sustratos nucleófilos en la organocatálisis.
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