スピロ炭素戦略を用いた立体規則性共役系高分子の創製

使用螺碳策略创建有规立构共轭聚合物

• 批准号: 15J05745
• 负责人: 徐 錦嘉
• 金额: $ 1.09万
• 依托单位: National Institute for Materials Science (2016)University of Tsukuba (2015)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for JSPS Fellows
• 财政年份: 2015
• 资助国家: 日本
• 起止时间: 2015-04-24 至 2017-03-31
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15J05745/
• 关键词: macrocyclization; bifluorenyldene; electron acceptors; twisted but conjugated; 立体規則性; 共役系高分子; ヘリシティ

a) I successfully established a straightforward approach to synthesize the highly strained 9,9’-bifluorenylidene cyclic dimer (CBF) from 9,9’-bifluorenylidene (BF) by unexpected intramolecular cyclization via typical Yamamoto coupling reaction conditions. Sequential Yamamoto coupling reactions potentially allowed us to obtain well-defined and highly twisted but conjugated 9,9'-BF ladder tetramer (LBF).b) The photophysical and electrochemical properties of BF and CBF were systematically investigated by using UV-vis absorption and CV measurements. The BF and CBF were demonstrated to have ability to accept two electrons, probably favored by release of steric hindrance from proximal aromatic rings and development of a 14- electron system.c) The thermal behavior and phase transition processes of BF and CBF was determined by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Characterization by DSC reveals no phase transitions between 25°C and 200°C for CBF, presumedly due to the existence of enantiomeric mixture namely (P, P) and (M, M), yielding CBF more amorphous than crystalline. In stark contrast, BF showed the broadening melting point at around 153°C in the second heating process, probably attributable to multi-conformations from BF. Surprisingly, in the cooling process, one sharp peak at 150°C in additional to one small peak at 154°C was observed, thus we infer that multiple phase transitions occur sequentially by alternating the conformation of BF.

a）我成功地建立了一种直接的方法，通过典型的Yamamoto偶联反应条件，通过意想不到的分子内环化，从9，9 '-二芴亚基（BF）合成高度应变的9，9'-二芴亚基环状二聚体（CBF）。顺序的Yamamoto偶联反应可能使我们能够获得结构明确且高度扭曲但共轭的9，9 '-BF梯形四聚体（LBF）。B）通过紫外-可见吸收和CV测量系统地研究了BF和CBF的物理和电化学性质。 结果表明，BF和CBF具有接受两个电子的能力，这可能是由于近端芳环空间位阻的释放和14电子体系的形成。c）通过热重分析（TGA）和差示扫描量热（DSC）研究了BF和CBF的热行为和相变过程。 通过DSC的表征揭示CBF在25°C和200°C之间没有相变，这可能是由于存在对映体混合物，即（P，P）和（M，M），产生比结晶更无定形的CBF。与此形成鲜明对比的是，BF在第二次加热过程中显示出约153°C的增宽熔点，这可能归因于BF的多构象。令人惊讶的是，在冷却过程中，除了在154°C处观察到一个小峰外，还在150°C处观察到一个尖锐峰，因此我们推断通过改变BF的构象而顺序发生多个相变。

项目成果

Multiple emissions from indenofluorenedione in solution and polymer films

• DOI: 10.1039/c6ra17765d
• 发表时间: 2016-08
• 期刊: RSC Advances
• 影响因子: 3.9
• 作者: Jinjia Xu;Atsuro Takai;M. Takeuchi

Full Color Fluorescence From RGB Trichromophoric Nanoparticle System Assisted by Dual-FRET in Aqueous Medium Towards Visual Bio-sensing

水介质中双 FRET 辅助下 RGB 三色纳米粒子系统的全色荧光迈向视觉生物传感

• 发表时间: 2015
• 作者: J. Xu;A. Takai;M. Takeuchi
• 通讯作者: M. Takeuchi