基结合宏循环和 [2]用于阳离子识别的罗塔克桑
Jason Y C Lim1, Igor Marques, Amber L Thompson1
1Chemistry Research Laboratory, Department of Chemistry, University of Oxford , Mansfield Road, Oxford OX1 3TA, U.K.
Journal of the American Chemical Society
|February 1, 2017
概括
这项研究引入了新的宏循环宿主,利用基键 (ChB) 进行离子识别. 这些系统在溶液和水性混合物中表现出有效的离子结合,为高级超分子化学应用铺平了道路.
科学领域:
- 超分子化学
- 有机化学
- 材料科学
背景情况:
- 缺电子的重原子与易斯基形成基键 (ChB),使得超分子相互作用成为可能.
- ChB在溶液相离子结合中的应用正在出现,特别是在非循环系统中.
- 将CHB供体纳入宏循环结构为宿主-客化学提供了更多的可能性.
研究的目的:
- 探索5- ((methylchalcogeno) -1,2,3-triazole基因作为在宏循环宿主中结合阴离子的新型ChB供体.
- 合成和表征具有 ChB 捐赠组的机械互锁 [2] 罗塔xanes.
- 研究这些新系统在有机和水性环境中的离子结合能力,阐明 ChB 的作用.
主要方法:
- 合成含有宏循环和罗塔克桑的5-甲基) -1,2,3-.
- H 核磁共振光谱用于结构特征和离子结合研究.
- 密度功能理论 (DFT) 计算和分子动力学模拟以了解结合机制和选择性.
- 在子识别过程中探测原子的电子环境的Se和TeNMR光谱.
主要成果:
- 成功地将5-甲基基-1,2,3-基基因组合到强大的宏环结构中.
- 通过宏循环腔内的石化原子证明铜的内位化.
- 使用活性金属模板策略制备第一种机械互锁 [2]的rotaxanes.
- H 核磁共振和分子建模证实了 ChB 在轮宿主的离子结合中的主导作用.
- 在水性混合物中观察到前所未有的电荷辅助ChB介导的离子结合,与无素类型相比具有不同的识别行为.
- DFT和分子动力学模拟显示,在水性介质中的离子选择性是由离子水友性和结合单元的水合性决定的.
- 和125NMR直接显示了离子结合如何影响原子的局部电子环境.
结论:
- 甲基基) -1,2,3-基基因为构建复杂的宏循环和机械互锁宿主系统的多功能基因供体.
- 即使在水性环境中,ChB在溶液相离子识别中也起着至关重要的作用.
- 开发的罗塔xane 系统具有可调的离子结合选择性,受 ChB 相互作用和溶剂作用的影响.
- 异核核磁共振光谱提供了ChB介导的离子识别及其对捐赠原子电子性质的影响的直接证据.
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