一种双[4]醇酶模拟剂,可以将两个离子紧密地约束在一起
Qing He1, Michael Kelliher1, Steffen Bähring1,2
1Department of Chemistry, The University of Texas at Austin , 105 East 24th Street-A5300, Austin, Texas 78712-1224, United States.
Journal of the American Chemical Society
|May 12, 2017
概括
一个新的囊状分子,bis-calix[4]pyrrole 1,可以同时结合两个离子,包括二酸盐,硫酸盐和酸盐. 这种双离子识别通过各种光谱和晶体学方法得到证实.
科学领域:
- 超分子化学
- 主机与客户之间的化学反应
- 离子识别
背景情况:
- 卡利克斯皮罗尔宏循环是分子识别的多功能平台.
- 设计可同时结合多个离子的受体是一个重大挑战.
研究的目的:
- 合成和描述一个大囊状的bis-calix[4]pyrrole受体.
- 调查受体同时接收多个阴离子的能力.
- 探索双离子结合的结构和电子基础.
主要方法:
- 双酸[4]醇受体的合成 1.
- 光谱分析 (1H NMR,紫外线).
- 异热定位热量计 (ITC).
- 一个单晶X射线衍射.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 受体1成功地在溶液中接收了两个二酸离子.
- 该受体还结合了两个硫酸盐离子,在固态和溶液中形成二聚体.
- 检测结果显示,受体1具有容纳2个三酸阳离子的能力.
- 结构和计算研究阐明了绑定模式和相互作用.
结论:
- 双[4]pyrrole 1 具有与双离子结合的显著能力.
- 接收器的大腔和结构特征有助于识别各种多离子.
- 这项工作推进了复杂的宿主分子的设计,
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