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Mizoroki-Heck Cross-coupling Reactions Catalyzed by Dichloro{bis[1,1',1''-(phosphinetriyl)tripiperidine]}palladium Under Mild Reaction Conditions
Published on: March 20, 2014
Catalizadores neutros de níquel (II) poliolefina de un solo componente que toleran los heteroátomos
1Arnold and Mabel Beckman Laboratories for Chemical Synthesis, California Institute of Technology, Pasadena, CA 91125, USA.
Science (New York, N.Y.)
|January 22, 2000
Resumen
Los nuevos catalizadores toleran las impurezas en la producción de polímeros. Estos sistemas avanzados permiten la síntesis eficiente de polietileno de alto peso molecular y olefinas funcionalizadas sin necesidad de cocatalizadores.
Área de la Ciencia:
- Química y catálisis de polímeros.
- Ciencia e ingeniería de materiales.
Sus antecedentes:
- Las poliolefinas constituyen más de la mitad de los 170 millones de toneladas métricas de polímeros producidos anualmente.
- Los catalizadores catiónicos convencionales para la síntesis de poliolefinas son sensibles a los heteroátomos (oxígeno, nitrógeno, azufre) y requieren materiales de partida y cocatalizadores de alta pureza.
Objetivo del estudio:
- Desarrollar nuevos catalizadores que sean tolerantes a los heteroátomos y materiales de partida menos puros para la síntesis de poliolefinas.
- Investigar la actividad y el rendimiento de estos nuevos catalizadores en la producción de polietileno de alto peso molecular y la polimerización de olefinas funcionalizadas.
Principales métodos:
- Desarrollo de una nueva familia de complejos neutros de metales de transición tardía.
- Probar la actividad catalítica y la tolerancia de estos complejos hacia heteroátomos y sustratos impuros.
- Caracterización de los polímeros resultantes, incluyendo el peso molecular y la funcionalidad.
Principales resultados:
- Los catalizadores desarrollados exhiben tolerancia a los heteroátomos y a los materiales de partida menos puros.
- Estos sistemas demuestran una alta actividad, produciendo polietileno de alto peso molecular.
- Los catalizadores polimerizan con éxito las olefinas funcionalizadas.
- No se requiere cocatalizador para estas reacciones.
Conclusiones:
- Se ha desarrollado con éxito una nueva clase de catalizadores de metales de transición tardía neutrales y tolerantes al heteroatomo.
- Estos catalizadores ofrecen un avance significativo con respecto a los sistemas catiónicos tradicionales, simplificando los requisitos de materia prima y ampliando el alcance de la polimerización de olefinas.
- La tecnología permite la producción eficiente de poliolefinas de alta calidad y polímeros funcionalizados.
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