π-共轭稠环骨架的高效构筑及超分子识别、自组装与光电性能研究

In this proposal, highly efficient synthetic strategies to access π-conjugated polycyclic scaffolds will be developed through chelation-assisted C–H bond direct (hetero)arylation/cyclization reaction. A large library of polycyclic arenes and polycyclic heteroarenes will be rapidly constructed through these synthetic methods. Polycyclic (hetero)aromatic hydrocarbons modified by electron-donor, such as triarylamine, carbazole, phenothiazine, phenoxazine, 5,10-dihydrophenazine and 9,10-dihydroacridine, as well as electron-acceptor, such as cyano group, malononitrile and thiadiazole, will be designed and prepared. The corresponding relationship between the spatial configuration and push-pull electronic effects of target compounds and their emitting properties will be investigated systematically for screening excellent luminescent materials. We will focus on the design and preparation of two kinds of luminescent materials with highly hybridized local and charge transfer (HLCT) excited state character and thermally activated delayed fluorescence (TADF), respectively. High performance organic electroluminescent devices based on these materials will be fabricated and the comparative study on the luminescence mechanism of the two kinds of materials will be performed. The supramolecular self-assembly and aggregation form of these polycyclic (hetero)aromatic hydrocarbons will also be investigated. The fluorescent probes based on polycyclic (hetero)aromatic hydrocarbons will be designed and prepared, the new supramolecular recognition systems based on these fluorescent probes will be developed, the host-guest recognition capabilities for various guests, such as anions, cations, amino acids, nucleic acids, peptides, proteins, will be investigated, and highly specific targeting reagents of cell organelles will be developed.

本申请拟以螯合导向的C–H键直接芳基化/环化反应为基础，发展若干类构建π-共轭稠环骨架的高效合成策略，快速构筑一系列稠环芳烃和稠杂芳烃化合物库。构筑三芳基胺、咔唑、吩噻嗪、吩噁嗪、5,10-二氢吩嗪、9,10-二氢吖啶等电子供体以及氰基、丙二腈、噻二唑等电子受体功能化的稠(杂)芳环化合物，探索化合物空间构型以及推-拉电子效应等对光电性能的影响，筛选高性能发光材料。重点发展具有杂化局域-电荷转移(HLCT)激发态特征以及热激活延迟荧光(TADF)特征的两类发光材料，制作相应的电致发光器件，并对二者的发光机制进行对比研究。研究稠(杂)芳环化合物的超分子自组装与聚集形态。构筑基于稠(杂)芳环化合物的荧光探针，发展新型超分子识别体系。研究它们对于阴、阳离子、氨基酸、核酸、肽、蛋白质等客体分子的识别作用，并进一步探索它们在高度专一性生物靶向试剂等方面的重要应用。

按照申请书的研究计划，本课题在发展C–H键活化新策略、探索π-共轭稠环化合物合成新方法、开发有机发光二极管(OLED)、有机场效应晶体管(OFET)新材料以及细胞器靶向新试剂方面取得了一系列创新性结果，在Angew. Chem. Int. Ed.、ACS Catal.、Chem. Sci.等学术期刊上发表学术论文16篇，申请发明专利2项。相关的研究工作主要包括：在芳基化/环化反应构筑稠环结构方面，发展了高效的RhCl3/AgTFA催化体系，实现了从廉价易得的原料出发快速构筑氧族元素掺杂的蒽嵌蒽骨架，通过硫原子氧化首次实现了从p型到n型硫杂蒽嵌蒽半导体材料的转化；通过铱催化体系，首次实现了苯甲酸的双芳基化/环化反应，开发了性能优异的磷光OLED主体材料，充分展现了C–H活化策略在发展有机光电材料上的优势；通过邻位C–H芳基化和芳基季铵化反应将偶氮芳烃与芳环稠合，发展了基于近红外发射的5,6-菲啰啉鎓的线粒体靶向荧光探针；发展了铑催化下异丁酰吲哚的杂芳基化及铜促进的分子内串联环化，成功构筑了菲酮型稠杂环骨架。通过Pd(II)催化区域选择性α-萘酰胺C8−H活化，一锅法合成了全碳骨架的[4]螺烯、[4,4]双螺烯和[4,5,4]三螺烯；通过极性反转策略快速构筑了基于吩嗪的热活化延迟荧光材料；实现了铱催化卡宾导向的四重C–H活化反应，快速构筑了咪唑并[1,2-f]菲啶鎓盐骨架；通过铑催化的亚砜亚胺与噻吩的C–H/C–H交叉偶联，发展了苯并噻吩并苯并噻吩及苯并噻嗪衍生物的新合成方法；通过瞬态导向策略，构筑了联芳基及稠环结构。在炔加成/环化反应构筑稠环结构方面，通过Rh催化的连续C‒H活化/炔加成环化反应，构筑了一类新的π+稠合吡咯骨架，实现了pH控制的细胞内选择性荧光成像；实现了联炔与二茂铁硫代酰胺的区域选择性加成/硫转移环化反应，开发了具有发光特性的拓展π-共轭的二茂铁稠环化合物。此外，还开发了铑催化下酚与芳胺的C−H/C−H交叉氧化偶联、苄硫醚与噻吩的C−H/C−H交叉氧化偶联、三唑并嘧啶与吲哚的C–H/C–H交叉氧化偶联以及铜催化下稠环芳烃的远程C–H键直接芳基化，用于构建联芳基结构。