皇冠结的寡二甲基作为分子执行的模型化合物
Bruno Jousselme1, Philippe Blanchard, Eric Levillain
1Groupe Systèmes Conjugués Linéaires, UMR CNRS 6501, Université d'Angers, 2 Boulevard Lavoisier, 49045 Angers, France.
Journal of the American Chemical Society
|January 30, 2003
概括
皇冠结合的寡质被合成并与金属酸复杂化. 阴离子结合诱导了构造变化,改变了联系统的电子性质和氧化还原潜力.
科学领域:
- 有机化学 有机化学
- 超分子化学 超分子化学
- 材料科学 材料科学 材料科学
背景情况:
- 基是有机合材料,在电子行业有潜在的应用.
- 宏观环形结构可以设计为结合特定的金属.
- 对于设计功能性材料来说,了解-系统的相互作用至关重要.
研究的目的:
- 用氧乙烯链合成新型冠结四 (4T) 和六 (6T).
- 调查阴离子结合特性及其对这些宏循环的电子结构的影响.
- 为了探索静电相互作用和离子复合后的形状变化之间的相互作用.
主要方法:
- 合成冠状结的四和六二.
- 使用 (1) H NMR 和紫外线对光谱学进行阴离子结合分析.
- 使用密度函数方法进行理论计算.
- 通过循环电压计进行电化学表征.
主要成果:
- 成功合成了4T和6T宏循环与氧乙烯链.
- 形成1:1复合体,其中含有Ba(2+),Sr(2+) 和Pb(2+) 电离子.
- 阴离子复合诱导了pi结合系统中的构造过渡.
- 理论预测显示了缩小了最高占成-最低未占用分子轨道间隙和减少了氧化还原潜力.
- 实验结果表明,氧化还原潜力 (E(0) ((1) 和E(0) ((2)) 的变化取决于阴离子结合常数和相互作用.
结论:
- 皇冠结合的寡基可以有效地结合特定的金属.
- 阴离子结合会引发显著的结构变化,影响结合系统的电子和氧化还原特性.
- 观察到的不寻常的氧化还原电位转移突显了这些超分子系统中静电力和结构重组之间的复杂相互作用.
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