具有特皮里丁单元的形状持久宏循环:结晶中的合成,表征和结构
Christian Grave1, Dieter Lentz, Andreas Schäfer
1Institut für Chemie, Freie Universität Berlin, Takustrasse 3, D-14195 Berlin, Germany.
Journal of the American Chemical Society
|June 5, 2003
概括
研究人员通过交叉合反应合成了大,形状持久的宏循环,其二单元宽度高达2纳米. 这些分子具有灵活的侧链,通过各种光谱和衍射方法进行了鉴定.
科学领域:
- 超分子化学 超分子化学
- 有机合成 有机合成
- 材料科学 材料科学 材料科学
背景情况:
- 形状持久的宏循环是超分子化学中至关重要的构建块.
- 氨酸单元是构建金属有机框架和协调聚合物的有价值的配体.
- 控制宏循环的大小和特性对于先进的材料设计至关重要.
研究的目的:
- 合成新型形状持久的宏循环,其中包含一个或两个特皮里丁单元.
- 为了实现大内部直径 (高达2 nm) 的宏循环.
- 研究侧链对溶解度,加工和晶体包装的影响.
主要方法:
- 对于宏观循环组件的过渡金属催化交叉合反应.
- 用灵活的hexyloxy或hexyloxymethyl侧链装饰前体.
- 使用MALDI-TOF质谱,2DNMR光谱和单晶X射线衍射进行了表征.
- 扫描道显微镜 (STM) 用于接口研究.
主要成果:
- 成功合成了具有一个或两个特皮里丁单元和内径高达2纳米的宏循环.
- 整体产量在8%至27%之间,制成量高达290毫克.
- 侧链工程改善了溶解性和加工.
- 晶体包装分析显示了对侧链数量和长度的依赖.
- 通过STM,通过溶液-HOPG接口观察到一个宏循环的有序物理吸收.
结论:
- 这项研究证明了一条可行的合成途径,以大,形状持久的含特皮里丁的宏循环.
- 灵活的侧链是提高加工能力和控制固态结构的有效方法.
- 合成的宏循环显示出在超分子化学和材料科学中的应用潜力.
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