共查询到20条相似文献,搜索用时 31 毫秒
1.
Hong Yang Dr. Mengqi Li Dr. Chong Li Dr. Qianfu Luo Prof. Dr. Ming-Qiang Zhu Prof. He Tian Prof. Dr. Wei-Hong Zhu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(22):8638-8648
Unprecedented dual aggregation-induced emission (AIE) behavior based on a steric-hindrance photochromic system is presented, with incorporation one or two bulky aryl groups, resulting in different flexibleness. The dual AIE behavior of open and closed isomers can be explained by restriction of intramolecular rotation (RIR), restriction of intramolecular vibration (RIV), and intermolecular stacking. The large bulky benzothiophene causes restricted rotation, enhancing the emission of open form in solution and weak π–π molecular packing, thereby efficiently enhancing the luminescence performance in the solid state. With incorporation of two large bulky benzothiophene groups, BBTE possesses the most outstanding AIE activity, undergoing highly efficient and reversible off-to-on fluorescence in film upon alternating UV and visible light irradiation along with excellent fatigue resistance. The off-to-on fluorescent photoswitch is successfully established in super resolution imaging. 相似文献
2.
Bo‐Wen Wang Kai Jiang Jian‐Xiao Li Shi‐He Luo Zhao‐Yang Wang Huan‐Feng Jiang 《Angewandte Chemie (International ed. in English)》2020,59(6):2338-2343
An efficient and readily scalable thioetherification between 1,1‐diphenylethene (DPE) and sodium arylsulfinate was developed for the synthesis of 1,1‐diphenylvinylsulfide (DPVS) with the yield up to 99 %. The photophysical properties of DPVS show that the introduction of arylsulfenyl groups onto the parent molecule DPE makes DPVS a novel type of aggregation‐induced emission (AIE) luminogen (AIEgen) with large Stoke's shift (up to 188 nm). These DPVS possess AIE properties due to restriction of intramolecular motions (RIM), as demonstrated by crystal structure analysis. Importantly, the AIE performance of DPVS can be applied to sense the nitroaromatic explosive picric acid in aqueous systems through a “turn‐off” response. 相似文献
3.
Restriction of Intramolecular Motions: The General Mechanism behind Aggregation‐Induced Emission 下载免费PDF全文
Nelson L. C. Leung Dr. Ni Xie Dr. Wangzhang Yuan Dr. Yang Liu Dr. Qunyan Wu Prof. Qian Peng Prof. Qian Miao Dr. Jacky W. Y. Lam Prof. Ben Zhong Tang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(47):15349-15353
Aggregation‐induced emission (AIE) has been harnessed in many systems through the principle of restriction of intramolecular rotations (RIR) based on mechanistic understanding from archetypal AIE molecules such as tetraphenylethene (TPE). However, as the family of AIE‐active molecules grows, the RIR model cannot fully explain some AIE phenomena. Here, we report a broadening of the AIE mechanism through analysis of 10,10′,11,11′‐tetrahydro‐5,5′‐bidibenzo[a,d][7]annulenylidene (THBDBA), and 5,5′‐bidibenzo[a,d][7]annulenylidene (BDBA). Analyses of the computational QM/MM model reveal that the novel mechanism behind the AIE of THBDBA and BDBA is the restriction of intramolecular vibration (RIV). A more generalized mechanistic understanding of AIE results by combining RIR and RIV into the principle of restriction of intramolecular motions (RIM). 相似文献
4.
Wei Zhang Jinfeng Liu Xinsheng Jin Xinggui Gu Xiao Cheng Zeng Xiao He Hui Li 《Angewandte Chemie (International ed. in English)》2020,59(28):11550-11555
Full quantum mechanical (FQM) calculation of the excited state of aggregation‐induced‐emission (AIE) materials is highly sought but still a challenging task. Herein, we employed the recently developed electrostatically embedded generalized molecular fractionation (EE‐GMF) method, a method based on the systematic fragmentation approach, to predict, for the first time, the spectra of a prototype AIE fluorophore: di(p‐methoxylphenyl)dibenzofulvene (FTPE). Compared to the single molecular or QM/MM calculations, the EE‐GMF method shows significantly improved accuracy, nearly reproducing the experimental optical spectra of FTPE in both condensed phases. Importantly, we show that the conventional restriction of the intramolecular rotation mechanism cannot fully account for AIE, whereas the two‐body intermolecular quantum mechanical interaction plays a crucial role in AIE. 相似文献
5.
Anion‐Coordination‐Induced Turn‐On Fluorescence of an Oligourea‐Functionalized Tetraphenylethene in a Wide Concentration Range 下载免费PDF全文
Jie Zhao Dong Yang Dr. Yanxia Zhao Prof. Xiao‐Juan Yang Prof. Yao‐Yu Wang Prof. Biao Wu 《Angewandte Chemie (International ed. in English)》2014,53(26):6632-6636
A tetrakis(bisurea)‐decorated tetraphenylethene (TPE) ligand ( L2 ) was designed, which, upon coordination with phosphate ions, displays fluorescence “turn‐on” over a wide concentration range, from dilute to concentrated solutions and to the solid state. The fluorescence enhancement can be attributed to the restriction of the intramolecular rotation of TPE by anion coordination. The crystal structure of the A4L2 (A=anion) complex of L2 with monohydrogen phosphate provides direct evidence for the coordination mode of the anion. This “anion‐coordination‐induced emission” (ACIE) is another approach for fluorescence turn‐on in addition to aggregation‐induced emission (AIE). 相似文献
6.
Synthesis and Design of Aggregation‐Induced Emission Surfactants: Direct Observation of Micelle Transitions and Microemulsion Droplets 下载免费PDF全文
Dr. Weijiang Guan Dr. Wenjuan Zhou Prof. Dr. Chao Lu Prof. Dr. Ben Zhong Tang 《Angewandte Chemie (International ed. in English)》2015,54(50):15160-15164
The direct visualization of micelle transitions is a long‐standing challenge owing to the intractable aggregation‐caused quenching of light emission in the micelle solution. Herein, we report the synthesis of a surfactant with a tetraphenylethene (TPE) core and aggregation‐induced emission (AIE) characteristics. The transition processes of surfactant micelles and the microemulsion droplets (MEDs) formed by the surfactant with a TPE core were clearly visualized by a high‐contrast fluorescence imaging method. The fluorescence intensity of the MEDs decreased as the size of MEDs increased as a result of weakening of the restriction of intramolecular rotation (RIR). The results of this study deepen our understanding of micelle‐transition processes and provide solid evidence in favor of the hypothesis that the AIE phenomenon has its origin in the RIR of fluorophores in the aggregate state. 相似文献
7.
Yujie Tu Junkai Liu Haoke Zhang Qian Peng Jacky W. Y. Lam Ben Zhong Tang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(42):15053-15056
Restriction of intramolecular motion (RIM), as the working mechanism of aggregation‐induced emission (AIE), cannot fully explain some heteroatom‐containing systems. Now, two excited states are taken into account and a mechanism, restriction of access to dark state (RADS), is specified to elaborate RIM and complete the picture of AIE mechanism. A nitrogen‐containing molecule named APA is chosen as a model compound; its weak fluorescence in solution is ascribed to the easy access from the bright (π,π*) state to the close‐lying dark (n,π*) state. By either metal complexation or aggregation, the dark state is less accessible due to restriction of the molecular motion leading to the dark state and elevation of the dark state energy, thus the bright state emission is restored. RADS is powerful in elucidating the AIE effect of molecules with excited states favoring non‐radiative decay, including overlap‐forbidden states such as (n,π*) and CT states, spin‐forbidden triplet states, and so on. 相似文献
8.
Guangfeng Li Zhixuan Zhou Chang Yuan Zhewen Guo Yuhang Liu Dong Zhao Kai Liu Jun Zhao Hongwei Tan Xuzhou Yan 《Angewandte Chemie (International ed. in English)》2020,59(25):10013-10017
Herein, the trackable supramolecular transformation of a two‐component molecular cage to a three‐component cage through supramolecular fusion with another two‐component molecular square is described. The use of tetraphenylethene (TPE), a chromophore with aggregation‐induced emission (AIE) character, as a component for the molecular cages enables facile fluorescence monitoring of the transformation process: while both cages exhibit fluorescence emission via the restriction of intramolecular motion of the TPE motif, the interactions between TPE and 4,4′‐bipyridine introduced in the supramolecular fusion process result in partial fluorescence quenching and shifts in the emission maximum. This study provides a simple and efficient approach towards complex supramolecular cages with emergent functions and demonstrates that AIE features could provide unique opportunities for the characterization of complex, dynamic supramolecular transformation processes. 相似文献
9.
ABSTRACTTetraphenylethylene (TPE) related (supra)molecules have been intensively investigated due to their aggregation-induced emission (AIE) effect based on the restriction of intramolecular rotation (RIR). Meanwhile, boron-dipyrromethene (BODIPY) tends to emit intense fluorescence with high quantum yields. Herein, we combined TPE, BODIPY and terpyridine (TPY) into one system to study the emissive behaviour of organic building block as well as a self-assembled metallo-supramolecule. The TPY and BODIPY substituents with bulky sizes provide strong hindrance to restrict the rotation of the phenyl groups on TPE, leading to enhancement of emissive properties in both solution and aggregation states. Furthermore, the BODIPY-TPE-TPY ligand (L) was assembled with Zn (II) through coordination-driven self-assembly to form a cyclic dimer (D) with typical AIE characteristics. 相似文献
10.
Chao Chen Xiang Ni Han‐Wen Tian Qian Liu Dong‐Sheng Guo Dan Ding 《Angewandte Chemie (International ed. in English)》2020,59(25):10008-10012
Host–guest complexation between calix[5]arene and aggregation‐induced emission luminogen (AIEgen) can significantly turn off both the energy dissipation pathways of intersystem crossing and thermal deactivation, enabling the absorbed excitation energy to mostly focus on fluorescence emission. The co‐assembly of calix[5]arene amphiphiles and AIEgens affords highly emissive supramolecular AIE nanodots thanks to their interaction severely restricting the intramolecular motion of AIEgens, which also show negligible generation of cytotoxic reactive oxygen species. In vivo studies with a peritoneal carcinomatosis‐bearing mouse model indicate that such supramolecular AIE dots have rather low in vivo side toxicity and can serve as a superior fluorescent bioprobe for ultrasensitive fluorescence image‐guided cancer surgery. 相似文献
11.
Dr. Jie Li Dr. Yang Zhang Dr. Ju Mei Dr. Jacky W. Y. Lam Prof. Jianhua Hao Prof. Ben Zhong Tang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(2):907-914
A novel molecular design strategy is provided to rationally tune the stimuli response of luminescent materials with aggregation‐induced emission (AIE) characteristics. A series of new AIE‐active molecules (AIE rotors) are prepared by covalently linking different numbers of tetraphenylethene moieties together. Upon gradually increasing the number of rotatable phenyl rings, the sensitivity of the response of the AIE rotors to viscosity and temperature is significantly enhanced. Although the molecular size is further enlarged, the performance is only slightly improved due to slightly increased effective rotors, but with largely increased rotational barriers. Such molecular engineering and experimental results offer more in‐depth insight into the AIE mechanism, namely, restriction of intramolecular rotations. Notably, through this rational design, the AIE rotor with the largest molecular size turns out to be the most viscosensitive luminogen with a viscosity factor of up to 0.98. 相似文献
12.
Hong Y Häussler M Lam JW Li Z Sin KK Dong Y Tong H Liu J Qin A Renneberg R Tang BZ 《Chemistry (Weinheim an der Bergstrasse, Germany)》2008,14(21):6428-6437
Biosensing processes such as molecular beacons require non-trivial effort to covalently label or mark biomolecules. We report here a label-free DNA assay system with a simple dye with aggregation-induced emission (AIE) characteristics as the fluorescent bioprobe. 1,1,2,2-Tetrakis[4-(2-bromoethoxy)phenyl]ethene is nonemissive in solution but becomes highly emissive when aggregated. This AIE effect is caused by restriction of intramolecular rotation, as verified by a large increase in the emission intensity by increasing viscosity and decreasing temperature of the aqueous buffer solution of 1,1,2,2-tetrakis[4-(2-triethylammonioethoxy)phenyl]ethene tetrabromide (TTAPE). When TTAPE is bound to a guanine-rich DNA strand (G1) via electrostatic attraction, its intramolecular rotation is restricted and its emission is turned on. When a competitive cation is added to the G1 solution, TTAPE is detached and its emission is turned off. TTAPE works as a sensitive poststaining agent for poly(acrylamide) gel electrophoresis (PAGE) visualization of G1. The dye is highly affinitive to a secondary structure of G1 called the G-quadruplex. The bathochromic shift involved in the G1 folding process allows spectral discrimination of the G-quadruplex from other DNA structures. The strong affinity of TTAPE dye to the G-quadruplex structure is associated with a geometric fit aided by the electrostatic attraction. The distinct AIE feature of TTAPE enables real-time monitoring of folding process of G1 in the absence of any pre-attached fluorogenic labels on the DNA strand. TTAPE can be used as a K+ ion biosensor because of its specificity to K+-induced and -stabilized quadruplex structure. 相似文献
13.
Jonathan M. Wong Ruizhong Zhang Peidong Xie Liuqing Yang Minlin Zhang Ruixue Zhou Ruiyao Wang Yue Shen Bing Yang Hong‐Bo Wang Zhifeng Ding 《Angewandte Chemie (International ed. in English)》2020,59(40):17461-17466
Elucidating the effects of crystallization‐induced blue‐shift emission of a newly synthesized di‐boron complex (DBC) by enhanced photoluminescence (PL) and electrochemiluminescence (ECL) in the annihilation pathway was realized for the first time. The 57 nm blue‐shift and great enhancement in the crystalline lattice relative to the DBC solution were attributed to the restriction of intramolecular rotation (RIR) and confirmed by PL imaging, X‐ray diffraction, as well as DFT calculations. It was discovered that ECL at crystalline film/solution interfaces can be further enhanced by means of both co‐reactant route and RIR. The RIR contributions with co‐reactant increased ECL up to 5 times more. Very interestingly, the co‐reactant system was found to give off a red‐shifted light emission. Mechanistic studies reveal that a difference between location of the ECL in the co‐reactant route and that in the annihilation pathway leads to an alternative emission wavelength. 相似文献
14.
Bimetallic Au2Cu6 Nanoclusters: Strong Luminescence Induced by the Aggregation of Copper(I) Complexes with Gold(0) Species 下载免费PDF全文
Xi Kang Shuxin Wang Yongbo Song Shan Jin Guodong Sun Prof. Haizhu Yu Prof. Manzhou Zhu 《Angewandte Chemie (International ed. in English)》2016,55(11):3611-3614
The concept of aggregation‐induced emission (AIE) has been exploited to render non‐luminescent CuISR complexes strongly luminescent. The CuISR complexes underwent controlled aggregation with Au0. Unlike previous AIE methods, our strategy does not require insoluble solutions or cations. X‐ray crystallography validated the structure of this highly fluorescent nanocluster: Six thiolated Cu atoms are aggregated by two Au atoms (Au2Cu6 nanoclusters). The quantum yield of this nanocluster is 11.7 %. DFT calculations imply that the fluorescence originates from ligand (aryl groups on the phosphine) to metal (CuI) charge transfer (LMCT). Furthermore, the aggregation is affected by the restriction of intramolecular rotation (RIR), and the high rigidity of the outer ligands enhances the fluorescence of the Au2Cu6 nanoclusters. This study thus presents a novel strategy for enhancing the luminescence of metal nanoclusters (by the aggregation of active metal complexes with inert metal atoms), and also provides fundamental insights into the controllable synthesis of highly luminescent metal nanoclusters. 相似文献
15.
Hexaphenylbenzene‐Based, π‐Conjugated Snowflake‐Shaped Luminophores: Tunable Aggregation‐Induced Emission Effect and Piezofluorochromism 下载免费PDF全文
Zheng‐Feng Chang Ling‐Min Jing Cong Wei Prof. Yu‐Ping Dong Prof. Yan‐Chun Ye Prof. Yong Sheng Zhao Prof. Jin‐Liang Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(23):8504-8510
In this work, two rigid, multiple tetraphenylethene (TPE)‐substituted, π‐conjugated, snowflake‐shaped luminophores BT and BPT were facilely synthesized by using a 6‐fold Suzuki coupling reaction. These molecules are constructed based on the nonplanar structure of propeller‐shaped hexaphenylbenzene (HPB) or benzene as core groups and TPE as end groups. As a result, they reserve the intrinsic aggregation‐induced emission (AIE) property of the TPE moiety. Meanwhile, both fluorescence quantum yield and piezochromic behavior in the solid state can be tuned or switched by inserting the phenyl bridges through changing the twisting conformation. The more extended structure BPT showed a much stronger AIE effect and higher ΦF,f in the solid state in comparison with that of BT. Furthermore, an excellent optical waveguide application of these molecules was achieved. However, the revisable piezofluorochromic behavior has only appeared when BT was ground using a pestle and treated with solvent. 相似文献
16.
Frank Würthner 《Angewandte Chemie (International ed. in English)》2020,59(34):14192-14196
Aggregation‐induced emission (AIE) has attracted considerable interest over the last twenty years. In contrast to the large number of available reviews focusing specifically on AIE, this Essay discusses the AIE phenomenon from a broader perspective, with an emphasis on early observations related to AIE made long before the term was coined. Illustrative examples are highlighted from the 20th century where fluorescence enhancement upon rigidification of dyes in viscous or solid environments or J‐aggregate formation was studied. It is shown that these examples already include typical AIE luminogens such as tetraphenylethylene (TPE) as well as stilbenes and oligo‐ or polyphenylenevinylenes and ‐ethynylenes, which became important fluorescent solid‐state materials in OLED research in the 1990s. Further examples include cyanine dyes such as thiazole orange (TO) or its dimers (TOTOs), which have been widely applied as molecular probes in nucleic acid research. The up to 10 000‐fold fluorescence enhancement of such dyes upon intercalation into double‐stranded DNA, attributable to the restricted intramolecular motion (RIM) concept, afforded commercial products for bioimaging and fluorescence sensing applications already in the early 1990s. 相似文献
17.
Hongjun Jin Hongpeng Li Zhiyang Zhu Jianbin Huang Yunlong Xiao Yun Yan 《Angewandte Chemie (International ed. in English)》2020,59(25):10081-10086
Hydration water greatly impacts the color of inorganic crystals, but it is still unknown whether hydration water can be utilized to systematically manipulate the emission color of organic luminescent groups. Now, metal ions with different hydration ability allow fine‐tuning the emission color of a fluorescent group displaying aggregation induced emission (AIE). Because the hydration water can be removed easily by gentle heating or mechanical grinding and re‐gained by solvent fuming, rewritable materials can be fabricated both in the hot‐writing and cold‐writing modes. This hydration‐facilitated strategy will open up a new vista in fine‐tuning the emission color of AIE molecules based on one synthesis and in the design of smart luminescent devices. 相似文献
18.
Mechanochromic Behavior of Aryl‐Substituted Buta‐1,3‐Diene Derivatives with Aggregation Enhanced Emission 下载免费PDF全文
Shangzhi Gu Tianye Zhou Chuanzhen Zhao Yuexin Guo Dr. Xiao Feng Prof. Bin Tong Dr. J. Bing Jianbing Shi Prof. Junge Zhi Prof. Yuping Dong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(29):8856-8861
Three tetra‐aryl substituted 1,3‐butadiene derivatives with aggregation enhanced emission (AEE) and mechanochromic fluorescence behavior have been rationally designed and synthesized. The results suggest an effective design strategy for developing diverse materials with aggregation induced emission (AIE) and significant mechanochromic performance by employing D ‐π‐A structures with large dipole moments. 相似文献
19.
Tailoring Fluorescence Emission of Diketopyrrolopyrrole Dyes by an Aggregation‐induced Emission Coupled Excited‐state Intramolecular Proton Transfer Process 下载免费PDF全文
Dr. Fuyong Wu Prof. Lingyun Wang Prof. Hao Tang Prof. Derong Cao Prof. Xiaofang Jiang 《化学:亚洲杂志》2018,13(8):950-954
Two diketopyrrolopyrrole derivatives ( DPP1 and DPP2 ) are used for generating multiple luminescent colors (yellow–orange–red–deep red) in solution, nanoparticle, aggregate and solid states through an aggregation‐induced emission (AIE) coupled excited‐state intramolecular proton transfer (ESIPT) process. They are potentially useful for bioimaging due to their good biocompatibility and large Stoke shifts. 相似文献
20.
Zhe Peng Zhi Wang Bin Tong Yingchun Ji Jianbing Shi Junge Zhi Yuping Dong 《中国化学》2016,34(11):1071-1075
In order to get an easy way to achieve the transformation from aggregation‐caused quenching luminophores (ACQphores) to aggregation‐induced emission luminogens (AIEgens), we took aldehyde groups as the modifying group to decorate anthracene. The fluorescence performances of 9‐anthraldehyde (AnA) and 9,10‐anthracenedicarboxaldehyde (AnDA) in solution and aggregated state were studied. We found out that the aldehyde group can transform anthracene with aggregation‐caused quenching properties to AIEgen. The single‐crystal structures analysis of AnA and AnDA showed that their structure characteristics are responsible for the AIE properties of AnA and AnDA. On one hand, the aldehyde group can cause steric effects to lower intermolecular π‐π packing style in aggregated state. On the other hand, intermolecular H‐bonding interactions can restrict the intramolecular rotation and suppress internal charge transfer. These results may supply a new simple method for the transformation from ACQphores to AIEgens on the point of the molecular design. 相似文献