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La polimerización catalizada por boro del dimetilsulfoxonio metilido. Una síntesis de polimetileno con vida
Brett B Busch1, Manuel M Paz, Kenneth J Shea
1Department of Chemistry, University of California Irvine, Irvine, California 92697-2025, USA.
Journal of the American Chemical Society
|April 4, 2002
Resumen
Los organoboranos catalizan la polimerización del dimetilsulfoxonio metilido para producir polimetileno. Este método permite pesos moleculares de polímeros controlados y altas frecuencias de rotación, lo que permite la síntesis de organoboranos estelares.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- La ciencia de los polímeros es la ciencia de los polímeros.
Sus antecedentes:
- Los organoboranos son catalizadores versátiles en la síntesis orgánica.
- El metiluro de dimetilsulfoxonio es un ylide reactivo con potencial para la polimerización.
Objetivo del estudio:
- Para investigar la polimerización catalítica del dimetilsulfoxonio metilido mediante el uso de organoboranos.
- Para caracterizar los productos de polimetileno resultantes y el mecanismo de reacción.
Principales métodos:
- La polimerización catalítica del dimetilsulfoxonio metilido con trialquilo y organoboranos arilo.
- Análisis del peso molecular del polímero, la polidispersidad y la estructura.
- Estudios cinéticos para elucidar el mecanismo de reacción.
Principales resultados:
- Se lograron pesos moleculares de polímeros controlados proporcionales a la proporción de ylide/borano.
- Sintetizó organoboranos estelares con pesos moleculares de hasta 1,5 millones.
- Se determinó una alta frecuencia de rotación (>6 x 10^6 g/mol/h) y un mecanismo de reacción que involucra un complejo zwitteriónico y la migración de grupos 1,2-alquilo.
Conclusiones:
- La polihomologación catalizada por organoborano ofrece una ruta controlada para la síntesis de polimetileno.
- El método es eficiente, produciendo polímeros con baja polidispersidad y permitiendo la creación de complejas arquitecturas poliméricas.
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