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Published on: November 21, 2017
Complejos bimetálicos de anilido-aldimina y zinc para la copolimerización de epoxido y CO2
Bun Yeoul Lee1, Heon Yong Kwon, Su Yeon Lee
1Department of Molecular Science and Technology, Ajou University, Suwon 443-749 Korea. bunyeoul@ajou.ac.kr
Journal of the American Chemical Society
|March 3, 2005
Resumen
Los nuevos complejos de zinc dinuclear derivados de los ligantes acíclicos bis ((anilido-aldimine) muestran una alta actividad en la copolimización de óxido de ciclohexeno/CO ((2). La actividad más alta se observó con el complejo 32, lo que demuestra un potencial significativo para la síntesis eficiente de polímeros.
Área de la Ciencia:
- Química organometálica Química orgánica de los metales.
- Catálisis de polimerización por catálisis de polimerización.
- Coordinación Química de la Coordinación
Sus antecedentes:
- Se sintetizaron compuestos acíclicos o-fenileno-ponteados bis ((anilido-aldimina) y estructuras macrocíclicas relacionadas.
- Estos ligandos sirven como precursores para nuevos complejos dinucleares de zinc.
Objetivo del estudio:
- Para sintetizar y caracterizar complejos dinucleares de mu-metilsulfinato y zinc.
- Evaluar la actividad catalítica de estos complejos en la copolimerización de óxido de ciclohexeno/CO2 .
- Para investigar la influencia de la estructura del ligando en el rendimiento catalítico.
Principales métodos:
- Síntesis de los compuestos acíclicos bis ((anilido-aldimina) y macrocíclicos.
- Formación de complejos dinucleares de mu-metilsulfinato de zinc a través de la reacción con Me(2)Zn y SO(2).
- Evaluación catalítica en la copolimerización de óxido de ciclohexeno/CO2 en condiciones diluidas.
- Caracterización estructural por cristalografía de rayos X para los complejos 34 y 40.
Principales resultados:
- Se obtuvieron cuantitativamente complejos dinucleares de mu-metilsulfinato de zinc (30-35).
- Los complejos 30-35 mostraron una alta actividad catalítica para la copolimización de óxido de ciclohexeno/CO2 en bajas concentraciones de zinc ([Zn]/[monómero] = 1:5600).
- El complejo 32 exhibió la actividad más alta, logrando un número de rotación de 2980 y un peso molecular de hasta 284.000 en [Zn]/[monómero] = 1:17.400.
- Los análogos macrocíclicos (36-40) mostraron una actividad insignificante.
Conclusiones:
- Los complejos de zinc dinuclear derivados de bis ((anilido-aldimina) acíclicos son catalizadores altamente activos para la copolimización de CO ((2) / óxido de ciclohexeno.
- La actividad catalítica es sensible a los sustituyentes ortopédicos N-arilo, siendo el complejo 32 el más eficaz.
- Estos hallazgos resaltan el potencial de los complejos de zinc dinuclear cuidadosamente diseñados para la síntesis eficiente y selectiva de polímeros.
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