通过立体选择性CH-π相互作用控制多芳香协调囊的螺旋性控制
Natsuki Kishida1, Hayate Sasafuchi1, Tomohisa Sawada1
1Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology 4259 Nagatsuta, Midori-ku Yokohama 226-8503 Japan yoshizawa.m.ac@m.titech.ac.jp.
Chemical science
|August 26, 2024
概括
纳米结构的性和螺旋性是通过多芳香囊和单糖之间的立体选择性CH-π相互作用来控制的. 这使得水中的选择性结合和可调的螺旋形状成为可能.
科学领域:
- 超分子化学 超分子化学
- 协调化学 协调化学
- 基拉尔识别 基拉尔识别 基拉尔识别
背景情况:
- 方形平面ML4单元是协调子的关键,但控制纳米结构的性和螺旋性是具有挑战性的.
- 非共价相互作用对于设计复杂的超分子架构至关重要.
研究的目的:
- 使用立体选择性CH-π相互作用,在M2L4多芳香囊中实现螺旋性控制.
- 为了研究这些囊中的单糖的选择性结合.
- 为了将单糖的配置与囊螺旋形状相关联.
主要方法:
- 从金属离子和曲的比斯皮里丁连接物中合成M2L4多芳香囊.
- 用水中的各种甲基化单糖体进行宿主-客体复合研究.
- 谱分析 (CD,NMR) 和理论计算以确定结构和相互作用.
- 镜光谱检测诱导螺旋性的探测.
主要成果:
- 单糖的定量结合 (Ka高达>10^8 M^-1) 通过宿主-客人CH-π相互作用.
- 从α/β混合物 (>80:20比) 中通过赤道异构组结合选择性地识别β-葡萄糖.
- 对于银河糖衍生物也观察到立体选择性结合.
- 单糖的轴/赤道配置决定了囊的螺旋形状.
- α-葡萄糖封装诱导强烈的单手宿主螺旋性,由强烈的棉花效应证明.
- 结合β-银糖会诱导相反的囊螺旋性.
结论:
- 立体选择性CH-π相互作用为控制多芳香囊的螺旋性提供了一个强大的策略.
- M2L4囊充当一种能够区分单糖异常物之间的性宿主.
- 这项工作展示了一种创新的方法,用于在溶液中创建可调整的性纳米结构.
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