电离四核宏环CaCo3复合物作为氧化和二氧化碳交替共聚的高度活性催化剂
Haruki Nagae1, Saki Matsushiro1, Jun Okuda2
1Department of Chemistry, Graduate School of Engineering Science, Osaka University Toyonaka Osaka 560-8531 Japan mashima@chem.es.osaka-u.ac.jp.
Chemical science
|August 11, 2023
概括
一种新型的阴阳性 - 复合物有效催化了氧化物和二氧化碳的共聚合. 这种催化剂保持了聚合物选择性和碳酸盐结合,即使在高CO2压力下.
科学领域:
- 催化剂是一种催化剂.
- 聚合物化学 聚合物化学
- 有机金属化学 有机金属化学
背景情况:
- 开发高效的催化剂,以共聚氧化物和二氧化碳的共聚合,对于可持续的聚合物生产至关重要.
- 氧化物 (PO) 和二氧化碳 (CO2) 的交替共聚化产生具有理想性质的聚碳酸盐.
研究的目的:
- 为了研究PO和CO2的交替共聚合的cationic异质四核复合体.
- 确定最佳条件和添加剂,以实现高催化活性和选择性.
主要方法:
- 合成和表征一个阴离子异质四核核-复合体.
- 对PO/CO2共聚合复合物的催化试验.
- 反应条件的优化,包括使用诸如三级anilinium盐之类的添加剂.
- 密度函数理论 (DFT) 计算以阐明反应机制.
主要成果:
- 含有和三种离子的阴离子异质四核复合体表现出高的催化活性.
- 第三级阿尼盐[PhNMe2H][B(C6F5) [4]被证明是最佳的添加剂,确保了聚合物选择性和碳酸盐结合.
- 即使在1.0 MPa的CO2压力下,也可以实现有效的催化.
- 与中性对应物相比,DFT的计算表明,阴离子复合物的反应途径更有利.
- 在Ca和Co离子之间灵活的配体交换被确定为平滑的共聚合的关键.
结论:
- 阴阳性-复合体是氧化物和二氧化碳交替共聚的高效催化剂.
- 使用特定的添加剂和了解连接物交换动态是优化这种催化过程的关键.
- 这项研究为从二氧化碳合成聚碳酸盐提供了一个有前途的途径.
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