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Síntesis enantioenriquecida de ciclopropenos con un estereocentro cuaternario, versátiles bloques de construcción

Misaki Uehara¹, Hidehiro Suematsu, Yoichi Yasutomi

¹Department of Chemistry, Faculty of Science, Graduate School, and Institute for Advanced Study, Kyushu University, Hakozaki, Higashi-ku, Fukuoka 812-8581, Japan.

Journal of the American Chemical Society

|November 2, 2010

Resumen

Los complejos de iridio ((salino)) catalizan eficientemente la ciclopropenación enantioselectiva utilizando varios compuestos diazo. Este método produce ciclopropenos altamente enriquecidos con enantio con carbono cuaternario funcionalizado, que sirven como versátiles bloques de construcción sintéticos.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
Catalización asimétrica por catálisis asimétrica.

Sus antecedentes:

Los ciclopropenos son valiosos intermediarios sintéticos.
El desarrollo de métodos enantioselectivos eficientes para la síntesis de ciclopropeno es crucial.

Objetivo del estudio:

Investigar la eficacia de los complejos de Iridium (salen) en la catalización de la ciclopropenación enantioselectiva.
Para explorar el uso de diversos compuestos diazo como precursores de carbenoides.

Principales métodos:

Utilizó complejos de iridio como catalizadores.
Empleó varios diazocompuestos donantes / aceptadores y aceptadores / aceptadores sustituidos (por ejemplo, α-aril-α-diazoacetatos, α-fenil-α-diazofosfonato).
Reacciones de ciclopropenación realizadas en condiciones optimizadas.

Principales resultados:

Se logró una ciclopropenación enantioselectiva eficiente.
Se obtienen ciclopropenos altamente enriquecidos con enantio (84-98% ee).
Ciclopropenos generados con un centro de carbono cuaternario funcionalizado.

Conclusiones:

Los complejos de iridio ((salina) son catalizadores efectivos para la ciclopropenación enantioselectiva.
La metodología desarrollada proporciona bloques de construcción versátiles para la síntesis orgánica.
Se observaron consistentemente altas enantioselectividades en diferentes precursores de diazo.

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