在自组装的Fe4L6子中,高效的远程立体化学通信和合作效应
Naoki Ousaka1, Sergio Grunder, Ana M Castilla
1Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom.
Journal of the American Chemical Society
|August 25, 2012
概括
研究人员使用奇拉胺和间距器创建了大型,光学活性铁 (Fe ((4) L ((6)). 他们观察到子和螺旋体形成之间的平衡,在更大的结构中具有远程立体化学合.
科学领域:
- 协调化学 协调化学
- 超分子化学 超分子化学
- 基质材料 基质材料 基质材料
背景情况:
- 金属有机的自组装是超分子化学的一个关键领域.
- 控制这些组件的立体化学和拓学对于开发先进的功能材料至关重要.
- 光学活跃的子对在选性催化和传感中的应用很有兴趣.
研究的目的:
- 为了合成和表征大型,光学活性铁 (Fe) 协调 (Fe4) L6)).
- 为了研究连接体结构的影响,特别是奥利戈-p-xylen间距长度和奇拉氨基体积,对子形成和立体化学.
- 探索这些性超分子结构中长距离立体化学合的现象.
主要方法:
- 线性5,5'-bis(2-formylpyridines) 连接体的合成,其间隔长度不同于oligop-p-xylene间隔长度 (n=0-3).
- 铁的自组装 (II) 协调 (Fe ((4) L ((6)) 和螺旋体 (Fe ((2) L ((3)) 使用奇拉胺.
- 谱学表征 (例如,NMR,UV-Vis) 和潜在的X射线晶体学以确定结构和立体化学.
- 解决方案行为的分析,以了解不同超分子架构的共存.
主要成果:
- 成功地准备了光学活跃的Fe ((4) L ((6) ,配有可调节的连接体间隔器.
- 观察了Fe ((4) L ((6) 和Fe ((2) L ((3) 螺旋体形成之间的平衡,这取决于奇拉胺的体积和间距长度.
- 在较大的子 (n=2,3) 中,金属中心之间的长距离 (>2 nm) 立体化学合的证明,由连接体刚性介导.
- 证据表明连接体几何学,而不是轮效应,促进立体化学通信.
结论:
- 性氨基和连接体几何学的固体质量在指导铁协调复合体的自我组装方面发挥着关键作用.
- 在Fe(4) L(6) 和Fe(2) L(3) 螺旋体的形成之间存在微妙的平衡,受硬质因素的影响.
- 在扩展的超分子系统中,可以实现远程立体化学通信,这突出了设计复杂的性架构的潜力.
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