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电化学和光化学驱动的圆环运动在不对称的铜 [2]-链酸盐中
Aude Livoreil1, Jean-Pierre Sauvage1, Nicola Armaroli1
1Contribution from the Laboratoire de Chimie Organo-Minérale, URA 422 du CNRS, Institut Le Bel, Université Louis Pasteur, 4 rue Blaise Pascal, 67070 Strasbourg, France, Dipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, 40126 Bologna, Italy, and Istituto FRAE/CNR, Via Gobetti 101, 40129 Bologna, Italy.
Journal of the American Chemical Society
|October 8, 2016
概括
研究人员使用铜模创建了一种新型不对称的 [2] - 链酸盐,具有两种不同的互锁环. 这种分子机器在协调状态之间表现出可切换的特性和可控的运动,在超分子化学中提供了新的可能性.
科学领域:
- 超分子化学
- 协调化学
- 材料科学
背景情况:
- 铜的三维模板效应在合成复杂的互锁环系统中发挥了重要作用.
- 在超分子化学中,设计具有明显的相互关联的分子是关键的挑战.
- 通过外部刺激控制分子运动和形状对于开发先进的分子机器至关重要.
研究的目的:
- 合成一种新的不对称的 [2]-catenate,其中包含 2,9-diphenyl-1,10-phenanthroline (dpp) 和 2,2',6',2''-terpyridine (terpy) 单位.
- 调查酸盐与铜I) 和铜II) 离子的双重协调模式.
- 探索不同协调状态之间的触发分子运动和形状变化.
主要方法:
- 使用铜 (I) 模板效应合成不对称的 [2]-链酸盐.
- 与铜 (I) 和铜 (II) 离子复合,形成不同的协调复合物.
- 电化学研究和紫外线光谱分析氧化还原行为和分子运动.
- 对分子重组速度的对比效应的研究.
主要成果:
- 一种由两种不同的互锁环组成的新型不对称[2]-酸盐成功合成.
- 观察到两种不同的协调模式:铜 (I) 协调到dpp单位,使得terpy自由,铜 (II) 协调到terpy,dpp处于外围.
- 通过改变铜的氧化状态来触发四,五坐标状态之间的分子运动,从而导致不同的分子形状和特性.
- 环运动的速度可以控制,在某些条件下观察到缓慢的重新排列,并通过化物等协调对象诱导快速的重新排列.
结论:
- 合成的不对称 [2] - 酸盐作为一种基于铜的氧化状态的可切换性质的分子机器.
- 这项研究证明了在复杂的超分子系统中精确控制分子运动和形状转变.
- 这项工作为设计响应性材料和先进的分子装置开辟了道路.
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