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Reacciones de alquilación catalítica enantio- y diastereoselectivas con las aziridinas

Thomas A Moss¹, David R Fenwick, Darren J Dixon

¹School of Chemistry, The University of Manchester, Oxford Road, Manchester M13 9PL, UK.

Journal of the American Chemical Society

|July 12, 2008

Resumen

Este estudio introduce la primera alquilación catalizada por transferencia de fase asimétrica utilizando N-sulfonilo aziridinas. Este método produce de manera eficiente productos valiosos de aminoetileno con alta enantioselectividad, lo que hace avanzar la síntesis asimétrica.

Área de la Ciencia:

Química orgánica es la química orgánica.
Catalización asimétrica por catálisis asimétrica.
Metodología sintética de la metodología sintética.

Sus antecedentes:

La catálisis de transferencia de fase (PTC) es una técnica poderosa para permitir reacciones entre fases inmiscibles.
La síntesis asimétrica tiene como objetivo crear moléculas quirales con un alto control estereoquímico.
Las N-sulfonil aziridinas son versátiles intermedios sintéticos.

Objetivo del estudio:

Desarrollar la primera reacción de alquilación catalizada por transferencia de fase asimétrica de ácidos de carbono con N-sulfonilo aziridinas.
Para lograr altos rendimientos y enantioselectividades en la síntesis de derivados de aminoetileno.

Principales métodos:

Se utilizan sales cuaternarias de amonio derivadas de la cinchona como catalizadores de transferencia de fase quiral.
Empleado N-o- ((trifluorometano) benzenosulfonil aziridina como el electrófilo.
Reacciones llevadas a cabo bajo condiciones básicas suaves con varios ácidos de carbono (pronucleófilos).

Principales resultados:

Se logró una apertura eficiente del anillo de las N-sulfonil aziridinas para obtener productos de aminoetileno.
Se obtienen altos rendimientos y enantioselectividades (hasta 97% ee) utilizando un catalizador de 10 mol %.
Produjo productos de alquilación de enantiopuro con altos rendimientos y diastereoselectividades (hasta 30:1 dr) a partir de aziridinas enantiopuro.

Conclusiones:

Estableció una nueva y eficiente alquilación catalizada por transferencia de fase asimétrica para las N-sulfonil aziridinas.
Demostró la utilidad de este método para sintetizar compuestos de aminoetileno enriquecidos enantioméricamente.
Destacó el potencial para acceder a moléculas quirales complejas a través de este enfoque catalítico.

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