合成,结构研究和计算评价的含有伊米达-2-塞隆的循环
Ahmed Hassoon Mageed1, Karrar Al-Ameed1
1Department of Chemistry, Faculty of Science, The University of Kufa P. O. Box 21 Najaf 54001 Iraq ahmedh.alameri@uokufa.edu.iq.
RSC advances
|June 16, 2023
概括
合成和结构性表征了具有意达-2-基的新型环素. 它们的构造受烯连接器的影响,在固体和溶液状态下进行了分析,揭示了syn和anti的安排.
科学领域:
- 超分子化学 超分子化学
- 有机合成 有机合成
- 结构化学 结构化学
背景情况:
- 环素是具有独特结构性质的宏环化合物.
- 伊米达-2-氨酸部分在分子设计中提供了新的功能.
- 了解构造性行为对于宿主-客体化学和材料科学至关重要.
研究的目的:
- 为了合成新型的循环含有意达-2-塞隆组.
- 为了研究这些新型旋的结构和构造特性.
- 为了阐明烯链接剂对旋风形状的影响.
主要方法:
- 通过伊米达和的反应合成伊米达-2-旋.
- 使用核磁共振 (NMR) 光谱 (1H和13C) 的结构阐明.
- 用于固态结构分析的X射线衍射研究.
- 密度函数理论 (DFT) 分析稳定性和能量解释.
主要成果:
- 通过各种西利烯单元连接的成功合成的伊米达-2-塞隆环.
- 在固体和溶液状态下观察到不同的形状偏好 (syn,anti,部分),取决于烯链接器 (o-, m-, p-xylylene, mesitylene).
- 确定了o-xylylene和mesitylene-m-cyclophane衍生物的稳定syn构造,类似于calix[4]arene圆构造.
- 在溶液中检测到多个p-xylylene和m-xylylene链接的环素的syn和anti conformations,在NMR时间表上没有观察到相互转换.
- 在固体状态下对p-xylylene链接的cyclophanes特征有三种构造 (syn,anti,部分圆),对于m-xylylene链接的cyclophanes特征只有anti.
结论:
- 伊米达-2-塞隆环的构造性行为在很大程度上取决于烯链接器的性质.
- 观察到的形状与DFT能源偏好分析相一致.
- 这些发现有助于理解宏循环结构动力学,并为设计新型超分子结构提供基础.
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