伪[1]Catenane型柱[5]thiacrown 其平面螺旋倒置由金属触发并由阴离子控制
Eunji Lee1, Huiyeong Ju1, In-Hyeok Park1
1Department of Chemistry and Research Institute of Natural Science , Gyeongsang National University , Jinju 52828 , S. Korea.
Journal of the American Chemical Society
|July 6, 2018
概括
研究人员使用金属离子和离子实现了单个分子的第一个奇拉反转. 在超分子化学的突破提供了对控制分子结构和功能的新见解.
科学领域:
- 超分子化学
- 有机化学
- 协调化学
背景情况:
- 性对于分子结构和功能至关重要,影响从纳米结构到生物学的领域.
- 控制和逆转分子性,特别是在单个分子中,仍然是一个重要的科学挑战.
- 柱体[n]及其衍生物是具有可调节性质的多功能宏循环宿主.
研究的目的:
- 在单个分子中进行金属离子和离子控制的奇拉反转.
- 调查阴离子在指导协调模式和影响奇拉逆转中的作用.
- 探索支柱[5]冠衍生物的超分子协调化学.
主要方法:
- 合成支柱[5]thiacrown (rac-L),一个伪[1]catenane型分子.
- 使用循环二元化和X射线晶体学分离和表征平面 - 奇拉类体 (in-pS-L和in-pR-L).
- 在各种离子 (ClO4-, NO3-, I-) 存在时,研究由Hg2+触发的奇拉逆转.
- 涉及离子交换和金属离子去除的可逆性研究.
- 晶体分析以阐明阴离子在指导内外协调模式中的作用.
主要成果:
- 通过Hg2+成功地诱导了in-pS-L向out-pR-L的平面性反转,特别是在ClO4-或NO3-等弱协调的离子的存在下.
- 通过指导Hg2+的外协调,强烈协调的阳离子,如I-阻止了奇拉逆转.
- 观察到的性反转归因于离子导向协调模式 (内对外协调) 的金属离子在冠腔内.
- 该系统在离子交换或金属离子去除时证明了可逆性.
结论:
- 这项研究提供了第一个由金属离子和离子协同作用的例子.
- 阴离子作为协调几何学的关键指导者,决定了性逆转所需的形状变化.
- 这些发现为超分子协调化学提供了新的视角,并为控制分子性提供了新的策略.
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