通过溶剂控制的和土保证的库库尔比图里尔/客 trimers 的形成
Doroteja Lončarić1,2, Fahimeh Movahedifar3, Jakub Radek Štoček1,2
1Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences Flemingovo nám. 2 160 00 Prague 6 Czech Republic jiri.kaleta@uochb.cas.cz.
Chemical science
|September 15, 2023
概括
当特定的离子存在时,黄[7]uril (CB[7]) 在DMSO中形成三元体,但只有当一个客分子占据CB[7]腔时. 由于溶解效应,这种子介导的三分化在DMSO中比水更受青.
科学领域:
- 超分子化学 超分子化学
- 主机和客人的化学反应
- 物理化学 物理化学
背景情况:
- 黄瓜[7]uril (CB[7]) 是一种宏环宿主,以封装各种客人而闻名.
- 溶剂极性显著影响宿主-客座综合体的行为和组装.
- 阴离子模板自组合是超分子化学的一个关键策略.
研究的目的:
- 为了研究不同溶剂中的Cucurbit[7]uril (CB[7]) 阴离子介导的自我组装.
- 阐明CB[7]三元体形成的结构特征和驱动力.
- 为了确定客人占用和阴离子大小在CB[7]三元化中的作用.
主要方法:
- 核磁共振 (NMR) 谱学用于监测三元化动力学.
- 计算化学,包括半经验和密度函数理论 (DFT) 方法.
- 连续溶解模型模拟溶剂效应.
主要成果:
- 特定的和土离子 (例如Na+,K+,Ca2+) 在DMSO中触发CB[7]三元化,但不是Li+或更大的离子.
- 三元化需要由客分子 (例如,阿达曼,三甲基) 占据CB[7]腔.
- 广泛的CH-O相互作用稳定了三元体结构,CB[7]边缘之间嵌入了阴离子.
结论:
- 乙基介导的三元化CB[7]是一个客体依赖的过程,在DMSO中比在水中更受青.
- 在DMSO中的CB[7]门户处的较低的溶解处罚促进了三元体的形成.
- 这项研究揭示了CB的新的自我组装行为[7],由特定的阴离子-客体相互作用和溶剂特性驱动.
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