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Los complejos de iridio Cp* dan lugar a la hidroxilación catalítica de alcano con la retención de la estereoquímica

Meng Zhou¹, Nathan D Schley, Robert H Crabtree

¹Chemistry Department, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, USA.

Journal of the American Chemical Society

|August 25, 2010

Resumen

Los complejos Cp*Ir catalizan la oxidación C-H utilizando el agua como fuente de oxígeno. Este proceso logra la hidroxilación estereospecífica, incorporando oxígeno-18 en el producto alcohólico.

Área de la Ciencia:

Química organometálica Química orgánica de los metales.
La catálisis de la catálisis.
Síntesis orgánica La síntesis orgánica.

Sus antecedentes:

La oxidación C-H es una transformación fundamental en la química orgánica.
El desarrollo de sistemas catalíticos eficientes y selectivos para la oxidación de C-H sigue siendo un desafío significativo.
Es muy deseable utilizar el agua como fuente verde de oxígeno para las reacciones de oxidación.

Objetivo del estudio:

Para investigar la actividad catalítica de los complejos Cp*Ir en reacciones de oxidación C-H.
Explorar el uso del agua como fuente de oxígeno en estas oxidaciones catalíticas.
Para determinar el resultado estereocímico y el mecanismo del proceso de hidroxilación.

Principales métodos:

Síntesis y caracterización de varios complejos Cp*Ir.
Reacciones de oxidación catalítica C-H utilizando nitrato de amonio cerico como el oxidante terminal.
Análisis estereoquímico de los productos de hidroxilación.
Estudios de etiquetado isotópico utilizando H(2) O(18).

Principales resultados:

Los complejos Cp*Ir catalizan efectivamente la oxidación C-H.
La hidroxilación de la cis-decalina y el 1,4-dimetilciclohexano se produce con la retención de la estereoquímica.
La incorporación de oxígeno-18 de H(2) O(18) en el producto cis-decalol confirma que el agua es la fuente de oxígeno.

Conclusiones:

Los complejos Cp*Ir representan un nuevo sistema catalítico para la hidroxilación estereospecífica de C-H.
El agua se puede utilizar de manera eficiente como fuente de oxígeno en estas transformaciones catalíticas.
La retención observada de la estereoquímica proporciona información sobre el mecanismo de reacción.

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