基因衍生子单元在充电的捐赠者-接受者 [2]链中具有的结构和共构效应
Ognjen S Miljanić1, William R Dichtel, Saeed I Khan
1California NanoSystems Institute and Department of Chemistry and Biochemistry, University of California, Los Angeles, Los Angeles, CA 90095, USA.
Journal of the American Chemical Society
|June 15, 2007
概括
通过点击化学和合反应合成了新的捐赠者-接受者 [2]链. 它们的机械互锁结构通过pi-pi和C-H...pi相互作用稳定,具有量化的旋转障碍.
科学领域:
- 超分子化学 超分子化学
- 有机合成 有机合成
- 材料科学 材料科学 材料科学
背景情况:
- 捐赠者-接受者链是机械互锁的分子,在分子机器中具有潜在的应用.
- 复杂联体的合成通常需要精确控制分子结构和非对应相互作用.
研究的目的:
- 为了合成新型的捐赠受体 [2] 连锁物,其中包括环 (CBPQT4+) 和1,5-二氧化纳 (DNP) 单位.
- 研究这些连锁链中控制机械互锁的结构特征和动态过程.
主要方法:
- 通过使用Cu+催化Huisgen 1,3-双极循环添加和Cu2+介导埃格林顿合,通过模板定向循环化合成 [2]catenanes的 [2]pseudorotaxanes.
- 使用X射线晶体学进行固态结构分析,以确认机械互锁性质并确定稳定相互作用.
- 可变温度1HNMR光谱法用于量化环系统和环旋障碍的旋转障碍.
主要成果:
- 成功合成了四种捐赠者-接受者 [2] 链,成功的循环化取决于链长度.
- 在X射线晶体学中,通过[pi...pi],[C-H...pi],[C-H...Omicron]相互作用,包括二次非对应接触,发现了稳定.
- 对/双旋转和CBPQT4+环旋转的障碍被量化,范围为13.1至17.5千卡的mol-1.
结论:
- 这项研究表明,一种可行的合成途径,使复杂的捐赠者-接受者 [2]catenanes.
- 非共价相互作用在稳定机械互锁架构方面发挥着至关重要的作用.
- 旋转障碍的趋势与供体宏循环的大小和硬质障碍相关.
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