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Hidrazinas y azidas a través de la hidrohidrazinación y hidroazidación catalizadas por el metal de las olefinas
Jérôme Waser1, Boris Gaspar, Hisanori Nambu
1Laboratorium für Organische Chemie, ETH Zürich, Hönggerberg HCI-H335, 8093 Zürich, Switzerland.
Journal of the American Chemical Society
|August 31, 2006
Resumen
El cobalto y el manganeso catalizan nuevas reacciones de hidrohidrazinación e hidroazidación para las olefinas. Estos métodos ofrecen vías eficientes hacia aminas funcionalizadas y versátiles intermediarios azidas.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis es la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- La hidroaminación de las olefinas es una transformación crucial en la síntesis orgánica.
- Los métodos existentes a menudo requieren sustratos pre-funcionalizados o condiciones duras.
Objetivo del estudio:
- Desarrollar nuevas reacciones de hidrohidrazinación y hidroazidación de olefinas catalizadas por Co y Mn.
- Establecer rutas sintéticas eficientes y versátiles para aminas funcionalizadas y compuestos relacionados.
Principales métodos:
- Utilizados catalizadores de cobalto (Co) y manganeso (Mn) para la funcionalización de las olefinas.
- Se emplean silanos como fuente de hidrógeno y azodicarboxilatos o sulfoniloazidos como fuentes de nitrógeno.
- Investigó la hidrohidrazinación de varias olefinas utilizando el di-tert-butilo azodicarboxilato.
- Desarrolló la hidroazidación de las olefinas utilizando azidas de sulfonilo y hidroperoxido de tert-butilo.
Principales resultados:
- Se ha logrado una hidrohidrazinación eficiente de una amplia gama de olefinas (mono-, di-, tri- y tetrasubstituidas) con una excelente tolerancia al grupo funcional.
- Implementó con éxito la hidroazidación de las olefinas mono-, di- y trisubstituidas, produciendo versátiles intermedios de alquilo azido.
- Se demostró que los azidos de alquilo obtenidos pueden convertirse fácilmente en aminas o triazoles libres.
- Los estudios mecanicistas preliminares sugieren una hidrocobaltación que limita la velocidad seguida de una aminación, con la posible participación de radicales intermedios.
Conclusiones:
- Las reacciones catalizadas por Co y Mn desarrolladas proporcionan nuevos y poderosos métodos para la funcionalización de las olefinas.
- Estas reacciones ofrecen ventajas claras en términos de alcance, tolerancia del grupo funcional y facilidad de uso.
- Los intermediarios de azida generados sirven como valiosos precursores para la síntesis de aminas y triazol.
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