在协调聚合物中双核金属循环的立体选择性结合
Andrei N Khlobystov1, Matthew T Brett, Alexander J Blake
1School of Chemistry, The University of Nottingham, University Park, Nottingham NG7 2RD, U.K.
Journal of the American Chemical Society
|May 29, 2003
概括
研究人员合成了金属循环,并研究了它们组装成聚合物的过程. 立体选择性聚合产生螺旋或非螺旋结构,受组装条件和连接体性质的影响,而同体性协会在能量上不那么有利.
科学领域:
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
背景情况:
- 具有协调不和的性金属中心的双核金属循环对于构建复杂架构具有兴趣.
- 了解这些金属循环的自我组装成聚合物框架对于设计新型材料至关重要.
研究的目的:
- 通过使用角形的外位联体,合成结构相关的双核金属循环.
- 首次系统地研究这些金属循环的自我组装到聚合物框架结构.
- 研究立体选择性聚合对螺旋和非螺旋协调聚合物的形成的影响.
主要方法:
- 合成双核金属循环[Cd(NO(3)) ((2) L](2) ,其中L是一个角形的外双联体.
- 在不同的条件下 (温度,带功能) 进行受控的自我组装实验.
- 螺旋和非螺旋聚合物复合物的隔离和特征.
- 理论计算晶格能量,以确认热力学有利性.
主要成果:
- 一系列双核金属循环的成功合成.
- 证明立体选择性同体结合会导致螺旋协调聚合物,而中联结合会产生非螺旋链.
- 特定条件 (温度) 的识别,有利于在[Cd(NO(3)) ((2) ((2,4'-pyacph) ](2) 金属循环中支持同体性与中体性协会.
- 通过理论计算证实,在能量方面,同体性协会比中体性协会更不利.
结论:
- 双核金属循环的立体选择性聚合是可控制的,导致不同的螺旋或非螺旋聚合物结构.
- 连接体设计和自我组装条件是指导特定超分子结构形成的关键因素.
- 在这些金属循环系统中,充满活力的景观更倾向于介质协会而不是同体协会.
相关概念视频
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