皮林替代的皮里丁胺胺的自我结合和酸芳香诱导的脱聚
Sung Kuk Kim1, Jong Min Lim, Tuhin Pradhan
1Department of Chemistry, The University of Texas at Austin , 105 East 24th Street, Stop A5300, Austin, Texas 78712-1224, United States.
Journal of the American Chemical Society
|December 17, 2013
概括
双烯功能化的针表现出明显的自我组装行为. 子1形成超分子聚合物,而子2保持单质,两种系统都对三二 (TNB) 产生光学变化.
科学领域:
- 超分子化学 超分子化学
- 有机化学 有机化学
- 材料科学 材料科学 材料科学
背景情况:
- 研究功能化有机分子的自我组装对于设计新材料至关重要.
- 基于Pyrene的系统因其光物理特性和自我关联能力而被广泛研究.
研究的目的:
- 探索和比较两个双烯功能 (1和2) 的自组装特性和光学特性.
- 了解分子结构对溶液和固态中自我关联的影响.
- 研究这些自组装系统对外界刺激的反应,如三二 (TNB).
主要方法:
- 双烯甲基胺功能化和 tweezers (1和2) 的合成和表征.
- 在不同度的有机溶液中进行光谱研究 (UV-Vis吸收,光发射).
- 自组装结构的固态特征.
- 使用相关含和无化合物的对照实验 (3-6).
- 使用密度函数理论 (DFT) 和时间依赖 DFT (TDDFT) 的计算分析.
主要成果:
- 1表现出度依赖的自我组装,在较高度和固态下在稀释溶液和线性超分子聚合物中形成分子内接触.
- 子2没有显示分子间的自我结合,只显示烯单体排放.
- DFT/TDDFT计算表明,子1的S1状态是发射性的,最低的垂直过渡是禁止的.
- 在固体状态下,无皮伦的控制化合物 (5和6) 也形成线性超分子阵列.
- 暴露于TNB会诱导子1的超分子聚合物的脱聚,导致颜色变化和光火,在子2中观察到类似但明显的光学变化.
结论:
- 针中的甲基胺连接器1促进了显著的分子间自我组装成线性超分子聚合物,与针不同2.
- tweezers 1 和 2 之间的结构差异导致了不同的光物理特性和自我关联行为.
- 子1的自组装结构可以被TNB可逆地破坏,证明了传感器应用的潜力.
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