聚酸和分子穿剂
David A Leigh1, Vanesa Marcos1, Tugrul Nalbantoglu1
1School of Chemistry, University of Manchester , Oxford Road, Manchester M13 9PL, United Kingdom.
Journal of the American Chemical Society
|May 5, 2017
概括
研究人员使用pyridyl-acyl hydrazone开发了可光/热切换的罗塔克桑. 这些分子机器展示了精确的宏观循环运动,为先进的分子穿铺平了道路.
科学领域:
- 超分子化学
- 有机化学
- 材料科学
背景情况:
- 罗塔克桑是机械互锁的分子,在分子机器中具有潜在的应用.
- 控制宏循环在轮轴上的位置对于它们的功能至关重要.
- 光/热可切换部分提供了对分子组装和功能的动态控制.
研究的目的:
- 合成和描述具有可光/热切换的酸结合点的新型罗塔.
- 根据水几何学 (E/Z异构体) 调查轮的立体选择性形成.
- 为了证明光和热诱导的宏循环在轮轴上的可控运动.
主要方法:
- 酸功能化轴的合成.
- 胺宏循环的模板导向自组装
- 使用X射线晶体学进行了鉴定.
- 使用紫外线照射进行光异构研究.
- 热交换的实验
主要成果:
- [2]使用E-hydrazone同位素作为模板,形成了高产量 (高达85%) 的rotaxanes.
- 在相似的条件下,Z-水同位素没有产生罗塔克桑.
- 在紫外线照射下,从E-到Z-rotaxane的光异构化得到98%的产量.
- 通过X射线结晶学发现了E-和Z-罗塔克桑的独特结模式.
- 分子穿显示了高位置完整性 (>95%) 和切换保真性 (98%) 的受控宏循环重新定位.
结论:
- 甲基酸部分作为一个有效的光/热可切换的结合部位,用于罗塔的形成.
- 对于定向的宏循环组件,水的E/Z几何非常重要.
- 光和热可以在分子航天器中可逆地控制宏循环位置,展示它们对纳米尺度设备的潜力.
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