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La aminohidroxilación intramolecular catalizada por el hierro (II) de las olefinas con hidroxilaminas funcionalizadas
Guan-Sai Liu1, Yong-Qiang Zhang, Yong-An Yuan
1Department of Chemistry, Georgia State University, 100 Piedmont Avenue SE, Atlanta, Georgia 30303, United States.
Journal of the American Chemical Society
|February 14, 2013
Resumen
Los nuevos catalizadores de hierro (II) permiten una eficiente diastereo-selectiva aminohidroxilación de las olefinas. Este proceso produce valiosos aminoalcoholes de alta selectividad, que ofrecen un control a través de la elección de ligandos y contraaniones.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- La catálisis es la catálisis.
- Metodología sintética de la metodología sintética.
Sus antecedentes:
- La aminohidroxilación es una transformación clave para la síntesis de aminoalcoholes.
- Desarrollar métodos catalíticos eficientes y selectivos sigue siendo un desafío.
Objetivo del estudio:
- Desarrollar nuevos catalizadores de hierro para la aminohidroxilación diastereoselectiva de las olefinas.
- Para investigar el mecanismo y el control de la selectividad en esta transformación.
Principales métodos:
- Catálisis utilizando nuevos complejos de hierro (II) con hidroxilaminas funcionalizadas.
- Catálisis asimétrica que emplea complejos quirales de hierro (II).
- Estudios mecanicistas preliminares.
Principales resultados:
- Se logró una eficiente aminohidroxilación intramolecular de las olefinas.
- Se observó una alta diastereoselectividad (hasta > 20:1).
- Se propuso un intermediario de nitrenoide de hierro, capaz de someterse a la aminohidroxilación o aziridinación.
Conclusiones:
- Los nuevos complejos de hierro ((II) son catalizadores efectivos para la aminohidroxilación diastereoselectiva.
- La selectividad se puede ajustar modificando las combinaciones de contraaniones y ligandos.
- Los hallazgos proporcionan una nueva ruta a los aminoalcoholes sintéticamente útiles.
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