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La escisión del dióxido de carbono por un carbono de Fischer soportado por iridio. Una investigación sobre el DFT
Nigel J Brookes1, Alireza Ariafard, Robert Stranger
1School of Chemistry, University of Tasmania, Private Bag 75, Hobart, Tasmania 7001, Australia.
Journal of the American Chemical Society
|April 3, 2009
Resumen
La teoría funcional de la densidad investigó las reacciones catalizadas por iridio. Este estudio racionaliza la escisión selectiva de enlaces en OCS y PhNCO, prediciendo la escisión preferencial de enlaces CS en MeNCS y descubriendo un mecanismo de formación de carbenos autocatalíticos.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Química computacional es la química computacional.
- La catálisis de la catálisis.
Sus antecedentes:
- Los complejos de alcoxicarbenos de Fischer soportados por iridio son catalizadores clave.
- La comprensión de los mecanismos de reacción es crucial para el diseño de catalizadores.
Objetivo del estudio:
- Investigar los mecanismos de reacción de CO2, OCS y PhNCO con un Fischer alkoxycarbene soportado con iridio.
- Racionalizar la escisión selectiva de los bonos CS y CN.
- Predecir la reactividad del tiocianato de metilo (MeNCS).
- Elucidar el mecanismo de formación del carbeno soportado por iridio.
Principales métodos:
- Se emplearon cálculos de la teoría funcional de la densidad (DFT).
- El modelado computacional se utilizó para analizar las vías de reacción.
Principales resultados:
- Se confirmó el mecanismo de la reacción de CO2 .
- Se racionalizó la escisión selectiva de bonos CS y CN en OCS y PhNCO.
- Se predice que el sistema de iridio escindirá preferentemente el enlace CS en MeNCS.
- Se descubrió un nuevo mecanismo autocatalítico para la formación de carbenos.
Conclusiones:
- El estudio proporciona conocimientos mecanicistas sobre las reacciones catalizadas por iridio.
- Los hallazgos apoyan el desarrollo de catalizadores selectivos.
- El mecanismo autocatalítico descubierto explica las observaciones experimentales.
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