在单分散性宏分子的模板导向合成中具有积极的合作性
Matthew E Belowich1, Cory Valente, Ronald A Smaldone
1Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3133, United States.
Journal of the American Chemical Society
|February 7, 2012
概括
合成的寡甲因合作[π··π]堆叠相互作用而表现出增强的形成效率和刚性. 这与灵活的类似物形成鲜明对比,突出了超分子化学中一种新的自我组装机制.
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:
- 模板导向合成可以构建复杂的分子架构,如寡.
- 具有特定识别位点的寡甲可以自组装成有序结构.
- 控制形状和组装效率对于设计新型材料至关重要.
研究的目的:
- 合成和描述两系列具有不同间隔单位的寡甲 (R和R').
- 调查[π···π]堆叠相互作用对形状特性和组装效率的作用.
- 阐明模板导向自组装中积极合作的机制.
主要方法:
- 模板导向合成使用2,6-二二甲和四乙烯基甘醇二 ((2-氨基) 乙烯.
- 使用高分辨率质谱 (HR-MS) 和核磁共振 (NMR) 谱学的表征.
- 使用离子流动性质谱学 (IM-MS) 和分子力学计算分析构造性质的分析.
主要成果:
- 具有三甲桥梁的R系列的寡甲因 [π···π] 堆叠而采用了刚性,棒状的外形.
- 在R'系列中的Oligorotaxanes,具有p-phenylene链接器,表现出灵活的形状.
- R系列显示出显著更高的产量 (88-98%) 和形成中的积极合作性,特别是在更高阶的寡中.
- 归因于稳定[π··π]堆叠的R系列的积极合作性,提高了每种 imine 债券的形成效率高达99.9%.
- 没有合作的R'系列显示出更快但更低的收益率 (72-85%).
结论:
- 延长的 [π···π] 堆叠相互作用是实现的关键,杆状的形状在寡头中.
- 积极的合作性显著提高了模板导向自组装过程的效率和产量.
- R系列代表了硬,高效的超分子结构的成功设计,与灵活的R'系列形成鲜明对比.
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