配平双核组4后金属代复合体,由化μ-(σ2-aryl) 连接体支持:表征和烯聚合催化
Yufang Li1, Qian Liu1, Junhui Bao1
1Department of Chemistry and Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China. mcwchan@cityu.edu.hk.
Dalton transactions (Cambridge, England : 2003)
|December 5, 2023
概括
具有锁定"syn"方向的新双金属催化剂显示了提高效率和聚合物特性. 这些刚性组件允许预先确定的金属-金属距离在聚合过程中进行合作反应.
科学领域:
- 有机金属化学 有机金属化学
- 催化剂是一种催化剂.
- 聚合物科学 聚合物科学
背景情况:
- 之前开发的M-[O,N,C] [皮里丁-2-烯酸-6-(σ-aryl) ]催化剂系统.
- 需要刚性,共平面双金属组件,可控制金属对金属的距离和基板接入.
研究的目的:
- 将催化剂系统扩展为刚性,共平面双金属组件.
- 研究合作反应性和催化性能.
主要方法:
- 双核复合物的区域选择性合成.
- 使用多核核核磁共振光谱学和X射线晶体学进行表征.
- 乙烯和乙烯/1-烯的聚合反应.
主要成果:
- 合成和表征了Ti,Zr和Hf的六种合成型双金属衍生物,其金属与金属的分离值为6.3-6.7 Å.
- 与反和单一Ti同类相比,Syn-Ti2催化剂表现出更高的效率和更高的分子量聚合物.
- 证明了有利的连锁相互作用和合作反应性.
结论:
- 刚性,同源导向的双金属催化剂在聚合过程中具有优势.
- 预先确定的金属对金属的距离和锁定基板的访问有助于合作效应.
- 开发高效的聚合催化剂的潜力.
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