TPE核的螺旋手性

正2001年,唐本忠等基于多苯环取代的噻咯衍生物在良溶剂中不发光或发光微弱,而在聚集状态下荧光大大增强的现象,率先提出了"聚集诱导发光(aggregation-induced emission,AIE)"的概念~1,经过大量实验验证和理论模拟,他们提出了分子内运动受限是导致化合物产生AIE现象的主     

聚集诱导发光

聚集诱导发光(AIE)是唐本忠院士于2001年提出的一个科学概念,是指一类在溶液中不发光或者发光微弱的分子聚集后发光显著增强的现象。高效固态发光的AIE材料有望从根本上解决有机发光材料面临的聚集导致发光猝灭难题,具有重大的实际应用价值。从分子内旋转受限到分子内运动受限,从聚集诱导发光到聚集体科学,AIE领域已经取得了许多原创性的成果。在本综述中,我们从AIE材料的分类、机理、概念衍生、性能、应用和挑战等方面讨论了AIE领域最近取得的显著进展。希望本综述能激发更多关于分子聚集体的研究,并推动材料、化学和生物医学等学科的进一步交叉融合和更大发展。     

具有聚集诱导发光性质的近红外荧光染料

聚集诱导发光(AIE)现象的发现为解决传统有机荧光分子在高浓度和聚集形态下存在的荧光猝灭问题提供了最佳方案,并实现了在光电器件、化学传感、生物成像和靶向治疗等众多领域的广泛应用.随着对AIE 发光机理研究的不断深入,AIE 分子体系得到了极大的扩展.其中,一类具有给体-受体结构的AIE分子能够显著降低分子能隙,使发光分...     

利用Reimer-Tiemann反应合成水杨醛缩肼聚集诱导发光分子的综合实验

聚集诱导发光(Aggregation-Induced Emission,AIE)分子是一类在聚集状态下表现出强烈荧光而在分散状态下荧光较弱甚至无荧光的分子。自2001年首例AIE分子被发现以来,各类新型AIE分子如雨后春笋般相继被开发出来,并在有机光电材料、荧光探针、生物成像等领域表现出非常广泛的应用。其中,水杨醛缩肼就是一类合成简单、荧光强度高的典型AIE分子。本论文介绍了利用Reimer-Tiemann反应合成水杨醛,并通过与水合肼反应进一步得到水杨醛缩肼AIE分子的方法。在本实验中,学生不但练习了经典Reimer-Tiemann反应的操作方法,同时也学习了水杨醛缩肼分子的AIE特性及其产生机理。结合拓展阅读,可使学生进一步了解AIE分子的应用。     

聚集诱导发光体系:化合物种类、发光机制及其应用

聚集诱导发光(AIE)体系是近年来备受关注的一个研究领域,目前该领域已经积累了较为丰富的AIE化合物的分子设计理念和相应的对AIE机制的理解。AIE体系的研究为固态强发光材料特别是备受聚集发光猝灭难题困扰的有机电致发光材料提供了全新的分子设计思路。本文纵观该领域的研究进展,对AIE化合物种类、发光机制及其相关应用做出了较为详尽的综述报道。具有AIE性质的化合物主要包括多芳基取代的杂环化合物、多芳基乙烯类化合物、分子内电荷转移化合物、含有氢键的化合物、聚合物等。这些化合物的AIE发光机制也各有不同,包括分子内旋转受限、非辐射失活衰减受限、分子构象扭曲以避免形成激基缔合物以及利用特殊的分子堆积方式如J-聚集、交叉分子堆积、由分子间的C—H…π作用或特殊的氢键作用形成相应的发光聚集体等。基于其特殊的AIE性能,AIE化合物可广泛应用于化学传感、生物传感、生物标记、电致发光以及逻辑门器件等领域。     

二苯乙烯基蒽衍生物:聚集诱导发光性质、机理及应用

与传统的发光分子相比,具有聚集诱导发光(AIE)性质的分子,在聚集态或固态条件下,由于独特的分子结构和聚集态结构,表现出显著增强的荧光发射,因而在光电器件、生物化学检测等领域展现出广阔的应用前景。本文总结了二苯乙烯基蒽(DSA)及其衍生物的AIE性质,分析了DSA类分子AIE现象的机理,如分子内转动受限、扭曲的分子结构及分子间聚集结构等,同时介绍了此类分子在固态发光、刺激-响应材料,以及生物检测和生物成像等方面的应用。     

多芳基吡咯衍生物的发光性质及其应用

荧光分子在良溶剂中基本不发光或发光较弱,而在聚集状态下发光较强的现象,称为聚集诱导发光(Aggregation-induced emission,AIE)现象,这与传统的聚集导致猝灭(Aggregation-caused quenching,ACQ)现象相反。本文研究了多苯基吡咯衍生物的结构与发光性能的关系。通过比较吡咯衍生物的单晶结构和发光性质发现扭曲的结构可以限制共轭发光基团的分子内旋转(RIR),这是产生AIE现象的主要原因。羧酸化的吡咯衍生物可以对Al³⁺实时、选择性检测。由DMF诱导的三苯基吡咯羧酸衍生物(TPPA)重结晶在固态时出现可控的荧光发射,它具备很好的温度选择性,响应迅速,并可以循环利用,这证明TPPA可以作为一种热响应材料用于温度监控设备中。     

聚集诱导发光应用研究进展

传统的荧光化合物在聚集态时,会导致荧光猝灭;而聚集诱导发光(AIE)化合物在溶液中单分子状态时呈现弱的荧光,但当形成聚集态时发出强的荧光,这是由于分子内旋转受阻(RIR)和聚集形态的改变所致.综述了2008年以来聚集诱导发光最新应用研究进展,如用以检测离子、气体、有机小分子、爆炸物、蛋白、酶等化学/生物传感器;向传统的聚集引起猝灭化合物引入AIE单元,制备高效固态发光器件等;通过压力、热、溶剂蒸汽等调控聚集态,构建可逆的刺激性多重响应材料;发展与生物体具有良好兼容性的聚集体杂化纳米颗粒(如荧光硅纳米颗粒、聚合物胶束、电解质等),以用于生物体内成像、结构解析及检测等.     

基于分子内旋转受限原理的线性共轭小分子的AIE性能研究

研究了6个线性共轭化合物4-丁基联苯(L1)、4,4’-二异丙基联苯(L2)、5,5’-二甲基-2,2’-联吡啶(L3)、2-([1,1’-联苯]-4-)噻吩(L4)、1,1’-联萘(L5)和5-苯基-2,2’-联噻吩(L6)的紫外-可见光谱和荧光发射光谱。结果表明,化合物L1、L2和L3均具有聚集诱导发光(AIE)性能,化合物L4、L5和L6则不具有AIE性能。该研究结果表明,二联苯(或两个简单芳杂环相连)系列化合物具有AIE性能,分子内旋转受限(RIR)是该系化合物产生AIE现象的机理。但是在二联苯的结构基础上继续增加链的长度,或者引入体积更大的芳环(萘环),化合物不再具有AIE性能。     

具有聚集诱导发光(AIE)性能的水杨醛希夫碱的合成与性能研究综合实验

介绍了一种基于水杨醛希夫碱结构的荧光分子的合成方法及其聚集诱导发光(Aggregation-Induced Emission,AIE)性能研究。本实验中,学生将掌握希夫碱类化合物的制备方法、荧光的基本原理和应用,并直观了解AIE现象和传统荧光分子聚集诱导淬灭(Aggregation-Caused Quenching,ACQ)现象的差别。结合课堂教学和拓展阅读,使学生进一步了解AIE分子的结构特点和设计思路。     

Recent Advances of AIE-Active Conjugated Polymers: Synthesis and Application

Conjugated polymers (CPs) have long been recognized as an important class of materials. The highly conjugated backbone of the CPs will facilitate the rapid exciton migration and result in amplification of fluorescence signals. However, CPs are likely to aggregate and form excimers in solid states, directly leading to the fluorescence quenching, namely aggregation-caused quenching (ACQ), hence inhibiting their prospective utilizations in a large degree. Since the effect of aggregation-induced emission (AIE) is opposite to that of notorious ACQ, the AIE has raised great attention from scientists. CPs with AIE or aggregation-enhanced emission (AEE) features may help to solve the ACQ problem and meanwhile impart polymers with new properties and practical applications. In this review, we summarize the recent progress on the preparation of CPs with AIE or AEE characteristics, where AIE-active luminogens are located at polymer backbones or pendants. Their potential applications including fluorescent sensors, biological probes, and active layers for the fabrication of light-emitting diodes are also described.     

Photoactivatable Aggregation‐Induced Emission Fluorophores with Multiple‐Color Fluorescence and Wavelength‐Selective Activation

Photoactivatable (caged) fluorophores are widely used in chemistry, materials, and biology. However, the development of such molecules exhibiting photoactivable solid‐state fluorescence is still challenging due to the aggregation‐caused quenching (ACQ) effect of most fluorophores in their aggregate or solid states. In this work, we developed caged salicylaldehyde hydrazone derivatives, which are of aggregation‐induced emission (AIE) characteristics upon light irradiation, as efficient photoactivatable solid‐state fluorophores. These compounds displayed multiple‐color emissions and ratiometric (photochromic) fluorescence switches upon wavelength‐selective photoactivation, and were successfully applied for photopatterning and photoactivatable cell imaging in a multiple‐color and stepwise manner.     

喹喔啉酮类JNK3抗肿瘤抑制剂的绿色合成——推荐一个综合化学实验

介绍了一个荧光光谱方面新的实验项目:以苝和六苯基噻咯作为发光物质的特征分子,通过测定其不同聚集状态下的荧光光谱,观察聚集荧光淬灭ACQ(aggregation-causedquenching)和聚集诱导发光AIE(aggregationinduced emission)两种不同的发光现象;利用晶体学数据库CCDC (Cambridge Crystallographic Data Centre)检索特征分子的晶体结构,从分子晶体结构层面分析AIE和ACQ发光现象产生的原因,在此基础上探讨不同发光机制和分子状态的关系。论文详细描述了实验的设计思想、实验内容和实验结论,并结合教学过程,分析了该实验在开阔学生视野、提高认知水平及培养科研素养等方面所取得的教学效果。     

Recent Process of Photo-responsive Materials with Aggregation-induced Emission

The research of photo-responsive materials, with changed absorption and emission under light stimulus, has drawn more and more attention due to their wide applications. However, most of them suffered from the notorious aggregation-caused quenching(ACQ) effect, which often led to the unconspicuous luminescent change in photo-responsive process. To solve this problem, the strategy of combining aggregation-induced emission(AIE) and photochromic properties was utilized, which largely enriched the phenomenon and application of photo-responsive materials. This short review summarized the recent progress of photo-responsive AIE materials with changed UV absorbance or PL phenomenon under UV-irradiation, including the types of molecular structures, internal mechanisms and the practical applications. Also, some outlooks were given on the further exploration of this field at the end of this paper.     

Aggregation-induced emission luminogens and tunable multicolor polymer networks modulated by dynamic covalent chemistry

Aggregation-induced emission(AIE) based luminescent materials are generating intensive interest due to their unique fluorescence in the aggregation state. Herein we report a strategy of dynamic covalent chemistry(DCC) controlled AIE luminogens for the regulation of multicolor emission in reversible covalent polymer networks. Tetraphenylethene derived ring-chain tautomers were prepared, and the emission was readily controlled through multimode, such as changing the solvent, adding the base, and d...     

Zinc (II) and AIEgens: The “Clip Approach” for a Novel Fluorophore Family. A Review

Aggregation-induced emission (AIE) compounds display a photophysical phenomenon in which the aggregate state exhibits stronger emission than the isolated units. The common term of “AIEgens” was coined to describe compounds undergoing the AIE effect. Due to the recent interest in AIEgens, the search for novel hybrid organic–inorganic compounds with unique luminescence properties in the aggregate phase is a relevant goal. In this perspective, the abundant, inexpensive, and nontoxic d¹⁰ zinc cation offers unique opportunities for building AIE active fluorophores, sensing probes, and bioimaging tools. Considering the novelty of the topic, relevant examples collected in the last 5 years (2016–2021) through scientific production can be considered fully representative of the state-of-the-art. Starting from the simple phenomenological approach and considering different typological and chemical units and structures, we focused on zinc-based AIEgens offering synthetic novelty, research completeness, and relevant applications. A special section was devoted to Zn(II)-based AIEgens for living cell imaging as the novel technological frontier in biology and medicine.     

High-Performance Quinoline-Malononitrile Core as a Building Block for the Diversity-Oriented Synthesis of AIEgens

In vivo fluorescent monitoring of physiological processes with high-fidelity is essential in disease diagnosis and biological research, but faces extreme challenges due to aggregation-caused quenching (ACQ) and short-wavelength fluorescence. The development of high-performance and long-wavelength aggregation-induced emission (AIE) fluorophores is in high demand for precise optical bioimaging. The chromophore quinoline-malononitrile (QM) has recently emerged as a new class of AIE building block that possesses several notable features, such as red to near-infrared (NIR) emission, high brightness, marked photostability, and good biocompatibility. In this minireview, we summarize some recent advances of our established AIE building block of QM, focusing on the AIE mechanism, regulation of emission wavelength and morphology, the facile scale-up and fast preparation for AIE nanoparticles, as well as potential biomedical imaging applications.     

A Novel L-Shaped Fluorescent Probe for AIE Sensing of Zinc (II) Ion by a DR/NIR Response

In the field of optical sensors, small molecules responsive to metal cations are of current interest. Probes displaying aggregation-induced emission (AIE) can solve the problems due to the aggregation-caused quenching (ACQ) molecules, scarcely emissive as aggregates in aqueous media and in tissues. The addition of a metal cation to an AIE ligand dissolved in solution can cause a “turn-on” of the fluorescence emission. Half-cruciform-shaped molecules can be a winning strategy to build specific AIE probes. Herein, we report the synthesis and characterization of a novel L-shaped fluorophore containing a benzofuran core condensed with 3-hydroxy-2-naphthaldehyde crossed with a nitrobenzene moiety. The novel AIE probe produces a fast colorimetric and fluorescence response toward zinc (II) in both in neutral and basic conditions. Acting as a tridentate ligand, it produces a complex with enhanced and red-shifted emission in the DR/NIR spectral range. The AIE nature of both compounds was examined on the basis of X-ray crystallography and DFT analysis.     

High‐Performance Quinoline‐Malononitrile Core as a Building Block for the Diversity‐Oriented Synthesis of AIEgens

In vivo fluorescent monitoring of physiological processes with high‐fidelity is essential in disease diagnosis and biological research, but faces extreme challenges due to aggregation‐caused quenching (ACQ) and short‐wavelength fluorescence. The development of high‐performance and long‐wavelength aggregation‐induced emission (AIE) fluorophores is in high demand for precise optical bioimaging. The chromophore quinoline‐malononitrile (QM) has recently emerged as a new class of AIE building block that possesses several notable features, such as red to near‐infrared (NIR) emission, high brightness, marked photostability, and good biocompatibility. In this minireview, we summarize some recent advances of our established AIE building block of QM, focusing on the AIE mechanism, regulation of emission wavelength and morphology, the facile scale‐up and fast preparation for AIE nanoparticles, as well as potential biomedical imaging applications.     

Recent Advances in Aggregation-Induced Emission Active Materials for Sensing of Biologically Important Molecules and Drug Delivery System

The emergence and development of aggregation induced emission (AIE) have attracted worldwide attention due to its unique photophysical phenomenon and for removing the obstacle of aggregation-caused quenching (ACQ) which is the most detrimental process thereby making AIE an important and promising aspect in various fields of fluorescent material, sensing, bioimaging, optoelectronics, drug delivery system, and theranostics. In this review, we have discussed insights and explored recent advances that are being made in AIE active materials and their application in sensing, biological cell imaging, and drug delivery systems, and, furthermore, we explored AIE active fluorescent material as a building block in supramolecular chemistry. Herein, we focus on various AIE active molecules such as tetraphenylethylene, AIE-active polymer, quantum dots, AIE active metal-organic framework and triphenylamine, not only in terms of their synthetic routes but also we outline their applications. Finally, we summarize our view of the construction and application of AIE-active molecules, which thus inspiring young researchers to explore new ideas, innovations, and develop the field of supramolecular chemistry in years to come.