通过Cy3PCuMe和 (Bipy) 2FeEt2Fe2Et2进行烯二烯聚合
Frank Schaper1, Stephen R Foley, Richard F Jordan
1Department of Chemistry, The University of Chicago, 5735 S. Ellis Avenue, Chicago, Illinois 60637, USA.
Journal of the American Chemical Society
|February 20, 2004
概括
在低温下,PCuMe经历可逆的连接物再分配,形成离子对. 这种复合物与自由三环基啡 (PCy(3) 一起,通过阴离子机制启动了烯烯聚合.
科学领域:
- 有机金属化学 有机金属化学
- 聚合物化学 聚合物化学
背景情况:
- 有机铜复合物是众所周知的各种化学转换的催化剂.
- 配体再分配和离子对形成可以显著影响反应性.
研究的目的:
- 为了研究Cy(3) PCuMe的低温行为.
- 为了阐明由有机铜复合体启动的烯烯聚合的机制.
主要方法:
- 核磁共振 (NMR) 光谱学以表征离子对.
- 对平衡的稳定度分析.
- 反向合成以确认离子对结构.
- 聚合实验用于研究启动机制.
主要成果:
- 在低温下,Cy(3) PCuMe会重新分布,形成离子对[Cu(PCy(3)) ((2)][CuMe(2) ].
- 离子对结构通过NMR和合成得到证实.
- 复合体1,自由的PCy(3) 和一个铁复合体启动了烯二聚合.
- 聚合过程是通过阴离子机制进行的,PCy(3) 是复合物1的主要发起物.
结论:
- 在Cy(3) PCuMe中低温联体的再分配导致离子对的形成.
- 三环化 (PCy(3)) 是烯酸聚合的关键启动剂,可以自由或从铜复合体中释放.
- 对于这些启动系统来说,阳离子聚合机制得到了证实.
相关概念视频
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The radical dimerization of ketones or aldehydes gives vicinal diols through a pinacol coupling reaction. However, the behavior of titanium metals used for the reaction as a source of electrons is unusual. When the reaction is carried out in the presence of titanium, diols can be isolated at low temperatures. Else titanium further reacts with diols, forming alkenes through the McMurry reaction.
Olefin Metathesis Polymerization: Acyclic Diene Metathesis (ADMET)
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