Department of Chemistry, Indian Institute of Engineering Science and Technology, Howrah-, 711103, India.
Department of Chemistry, Jadavpur University, Kolkata, 700032, India.
Chemistry. 2019 Mar 27;25(18):4856-4863. doi: 10.1002/chem.201900312. Epub 2019 Mar 8.
In the present study, the carbazole and 2,3,3-triphenylacrylonitrile (TPAN) nanostructures (2-CTPAN and 2,2'-CTPAN) have been designed and synthesized by Pd-catalyzed Sonogashira cross-coupling reaction. CTPAN exhibit aggregation-induced emission enhancement (AIEE) behavior in water with high fluorescence quantum yield. Both the compounds show tunable self-assembly in water as well as in N,N-dimethylformamide (DMF) by extended π-π stacking interactions. CTPAN can be self-assembled into spherical particles in water and the structures of these self-assemblies have been investigated using X-ray diffraction. Interestingly, 2-CTPAN and 2,2'-CTPAN form organogels with a critical gelation concentration (CGC) of 11 and 15 mg mL , respectively, in DMF and exhibit acicular and rod shaped morphology, respectively. The single-crystal structure of 2-CTPAN shows that the intermolecular C-H⋅⋅⋅π interactions lock the molecular conformation into a staircase-shaped supramolecular assembly. These AIEE active compounds reveal high water dispersibility, strong yellow fluorescence with high quantum yield, promising photostability and excellent biocompatibility, which make them potential bioimaging agents.
在本研究中，咔唑和 2,3,3-三苯基丙烯腈（TPAN）纳米结构（2-CTPAN 和 2,2'-CTPAN）通过钯催化的 Sonogashira 交叉偶联反应设计和合成。CTPAN 在水中表现出聚集诱导发射增强（AIEE）行为，具有高荧光量子产率。这两种化合物通过扩展的 π-π 堆积相互作用在水中以及 N,N-二甲基甲酰胺（DMF）中均表现出可调的自组装。CTPAN 可以在水中自组装成球形颗粒，并且使用 X 射线衍射研究了这些自组装体的结构。有趣的是，2-CTPAN 和 2,2'-CTPAN 在 DMF 中分别以 11 和 15mg·mL-1 的临界凝胶浓度（CGC）形成有机凝胶，分别呈现针状和棒状形态。2-CTPAN 的单晶结构表明，分子间的 C-H···π 相互作用将分子构象锁定为阶梯状超分子组装。这些 AIEE 活性化合物具有高水分散性、高量子产率的强黄色荧光、良好的光稳定性和优异的生物相容性，使其成为潜在的生物成像剂。
