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Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
Published on: July 28, 2022
Reacciones asimétricas en tándem de Aza-Darzens y apertura de anillos: doble funcionalidad del ácido silano-lewis
S Corey Valdez1, James L Leighton
1Department of Chemistry, Columbia University, New York, New York 10027, USA.
Journal of the American Chemical Society
|September 26, 2009
Resumen
Este estudio presenta un nuevo método para sintetizar moléculas orgánicas complejas. Un ácido de Lewis silano quiral facilita reacciones altamente selectivas, produciendo valiosos ésteres beta-cloro-alfa-hidrazido y derivados de diarylalanina.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Síntesis asimétrica de síntesis.
- La catálisis de la catálisis.
Sus antecedentes:
- Los ilidos de azufre son reactivos versátiles en la síntesis orgánica.
- Las N-acilhidrazonas son importantes intermediarios sintéticos.
- La catálisis con ácido de Lewis quiral permite transformaciones enantioselectivas.
Objetivo del estudio:
- Desarrollar una síntesis altamente diastereoselectiva y enantioselectiva de los ésteres beta-cloro-alfa-hidrazido.
- Para lograr una síntesis de una sola olla de derivados de diarylalanina utilizando un ácido de Lewis silano quiral.
- Para explorar el doble papel del ácido de Lewis silano en la activación de los intermediarios.
Principales métodos:
- Generación catalizada por el rodio de un yiloide de azufre estabilizado a partir de Ph ((2) S y diazoacetato de etilo.
- La adición del ylide de azufre a las N-acilhidrazonas promovida por un ácido de Lewis silano quiral.
- Reacción de una sola olla que involucra arenas ricas en electrones y ZnCl(2) para la síntesis de diarilalanina.
Principales resultados:
- Logró una síntesis altamente diastereoselectiva y enantioselectiva de ésteres beta-cloro-alfa-hidrazido.
- Con éxito sintetizó derivados de diarylalanina en una sola olla, de manera altamente selectiva.
- Demostró la actividad catalítica del ácido Lewis silano en la activación de los intermediarios de la aziridina.
Conclusiones:
- El método desarrollado ofrece una ruta eficiente a moléculas quirales complejas.
- El silano quiral ácido de Lewis juega un papel crucial en el ciclo catalítico.
- Este enfoque proporciona una poderosa herramienta para la síntesis asimétrica de valiosos compuestos orgánicos.
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