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Reducción radical de la cadena de los compuestos de alquilborón con los catecolos
Giorgio Villa1, Guillaume Povie, Philippe Renaud
1Department of Chemistry and Biochemistry, University of Bern, Freiestrasse 3, 3012 Bern, Switzerland.
Journal of the American Chemical Society
|February 24, 2011
Resumen
Un nuevo método de radicales leves convierte a los organoboranos en alcanos utilizando 4-tert-butylcatechol como fuente de hidrógeno. Esta eficiente reacción en cadena ofrece una alternativa más ecológica a la tradicional protonólisis a alta temperatura para varios compuestos de organoboron.
Área de la Ciencia:
- Química orgánica es la química orgánica.
- Química Radical La Química Radical es una ciencia
- Química organometálica Química orgánica de los metales.
Sus antecedentes:
- La conversión tradicional de los alquilboranos en alcanos a través de la protonólisis requiere condiciones duras (alta temperatura, ácidos fuertes).
- Se necesita un método más suave y eficiente para la transformación de organoboranos en alcanos.
- Las reacciones radicales ofrecen potencial para rutas sintéticas más suaves.
Objetivo del estudio:
- Desarrollar un procedimiento de radicales leves para la transformación de organoboranos en alcanos.
- Para investigar el uso de 4-tert-butylcatechol como fuente de átomo de hidrógeno en esta transformación.
- Para determinar las constantes de velocidad para la transferencia de hidrógeno entre los radicales alquilo secundarios y los derivados de catecol.
Principales métodos:
- Utilizado 4-tert-butylcatechol como iniciador radical y fuente de átomos de hidrógeno.
- Estableció un mecanismo eficiente de reacción en cadena de radicales.
- Aplicó el método a varios derivados del organoboron, incluidos los B-alquilcatecolboranos, los trialquilboranos, los pinacolboronatos y los ácidos alquilborónicos.
Principales resultados:
- Convirtió con éxito una amplia gama de organoboranos en alcanos bajo condiciones suaves.
- Se ha demostrado la propagación eficiente de la cadena radical que involucra a los radicales fenoxilo.
- Constantes de velocidad determinadas experimentalmente para la transferencia de hidrógeno, que muestran que los catecolos son donantes efectivos de hidrógeno.
Conclusiones:
- Desarrolló un método radical suave y eficiente para la conversión de organoborano a alcano.
- El 4-tert-butylcatechol sirve como una fuente efectiva de átomos de hidrógeno, lo que permite una nueva vía sintética.
- Las constantes de velocidad determinadas destacan el potencial de los catecolos en las reacciones de formación de enlaces C-C mediadas por radicales.
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