基于蒂奥芬的双螺旋:合成,X射线结构和手术特性
Sheng Zhang1, Xinming Liu2, Chunli Li1
1Engineering Research Center for Nanomaterials, Henan University , Kaifeng 475004, China.
Journal of the American Chemical Society
|July 22, 2016
概括
研究人员使用循环甲基基有效合成联双螺旋梯形寡合物. 这些新型结构表现出高稳定性和强烈的光学特性,超越了类似化合物的特性.
科学领域:
- 有机化学
- 超分子化学
- 材料科学
背景情况:
- 结合的有机分子对于先进的材料至关重要.
- 开发具有可调节性质的新型螺旋结构仍然是一个挑战.
- 循环酸 (COTh) 为分子设计提供了独特的形支架.
研究的目的:
- 展示一种简单高效的方法来构造结合的双螺旋梯寡合体.
- 合成和描述基于COTh构建块的新型寡合物.
- 研究这些螺旋结构的光学特性和种族化障碍.
主要方法:
- 用n-BuLi对四[3,4]乙烯 (β,β-COTh) 进行选择性合.
- 种族前体的二重选择性合形成双螺旋梯形寡合体 (rac-DH-1,rac-DH-2,rac-DH-3).
- 用于结构阐明的X射线晶体学,用于分辨率的合性高性能液体染色学 (HPLC) 和合光学测量 (CD,光学旋转).
主要成果:
- 成功合成了三种具有不同数量的COTh单元的赛米双螺旋梯寡合体.
- 通过X射线结晶学证实了相互交织的双螺旋结构.
- 解析的DH-1-D反体表现出强烈的光学特性 (g = -0.039) 和高的种族化屏障 (ΔG‡ > 48 kcal mol−1).
结论:
- 从COTh建立了一个强大的合成路径,以结合双螺旋梯类寡合物.
- 这些寡合物具有显著的结构刚性和高反体稳定性.
- 增强的奇罗光学特性表明在奇拉材料和分子识别中的潜在应用.
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