Laboratory for Molecular Electronics and Photonics, Katholieke Universiteit Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium.
J Am Chem Soc. 2011 Feb 9;133(5):1317-27. doi: 10.1021/ja104978t. Epub 2011 Jan 6.
A concept of chiral, X-type organized π-conjugated oligomers, linked by means of a binaphthalene pincer, is presented. NMR spectroscopy and cyclic and differential pulse voltammetry indicate that these oligomers are in close proximity and influence each other in a through-space manner in their neutral as well as in their oxidized states. The interaction between the oligomers was also confirmed by UV-vis, CD, and emission spectroscopy. The synthetic versatility of this design also enables the development of heterocoupled binaphthalene derivatives BN1-2 and BN1-3, consisting of an electron-neutral oligothiophene or electron-rich oligomer and an electron-poor oligothiazole. Hyper-Rayleigh scattering data show a significant enhancement of the second-order nonlinear hyperpolarizability β for BN1-3 and BN1-2, in contrast with the homocoupled binaphthalene derivatives (BN1-1, BN2-2, and BN3-3). This enhancement provides direct proof for the through-space charge-transfer interaction between the p-type and the n-type oligomers within BN1-3 and BN1-2.
提出了一种手性 X 型组织的π共轭寡聚物的概念，通过联萘钳连接。NMR 光谱、循环伏安法和差分脉冲伏安法表明，这些寡聚物在中性和氧化态下非常接近，并且以通过空间的方式相互影响。寡聚物之间的相互作用也通过紫外可见光谱、圆二色光谱和发射光谱得到证实。这种设计的合成多功能性还使电子中性寡噻吩或富电子寡聚物与缺电子寡噻唑组成的杂耦合联萘衍生物 BN1-2 和 BN1-3 的开发成为可能。超瑞利散射数据表明，BN1-3 和 BN1-2 的二阶非线性超极化率β显著增强，与同偶联联萘衍生物（BN1-1、BN2-2 和 BN3-3）形成对比。这种增强为 BN1-3 和 BN1-2 内 p 型和 n 型寡聚物之间的通过空间电荷转移相互作用提供了直接证据。
