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Yu, Wai Hong. "Synthesis, Characterization and application studies of new aggregation-induced emission (AIE)-active materials." HKBU Institutional Repository, 2018. https://repository.hkbu.edu.hk/etd_oa/496.
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The structural design, synthesis and characterization of luminogens with aggregation-induced emission (AIE) properties are studied in this thesis. The remarkable emission properties, thermal stability and biocompatibility of the AIE-active materials demonstrate the promising applications in bioimaging and organic light-emitting diodes (OLEDs).;Chapter 1 introduces the existence of aggregation-caused quenching (ACQ) effect in most conventional organic dyes as well as phosphorescent transitional metal complexes. Discovery of AIE and its mechanical study allow further exploration of usage in organic luminescent materials. This chapter also gives some examples and the applications these AIE-active compounds.;In Chapter 2, a series of cyanostilbenes with simple electron donor (D)-p-electron acceptor (A) structure are presented and synthesized. They exhibit remarkable AIE effect as well as deep red emission peak in 95 % water fraction in THF. These results indicate that attachment of these electron acceptors provides alternative strategy for designing highly emissive AIE-active materials.;In Chapter 3, strongly emissive cyanostilbenes with phenothiazine unit are designed and synthesized. This chapter also investigates the effect of substituents in phenothiazine and terminal cyanostilbene on the photophysical properties and AIE effect. The results suggest that they are AIE-active with different sizes in nano-aggregates. Furthermore, these dyes exhibit clear and strong fluorescence in live cell imaging with excellent biocompatibility.;In Chapter 4, a series of AIE-active phosphorescent Pt(II) complexes made up of C^N^C tridentate ligands are designed and synthesized. They exhibit different morphologies and emission properties upon aggregation in 90 % water in acetonitrile although similar tridentate ligands are applied. One of the complexes in this chapter show nano-rod formation with the highest quantum efficiency in aggregated state, suggesting that rapid self-assembly process occurs to prevent non-radiative decay and oxygen quenching.;In Chapter 5, a series of bis-cyanostyryl fluorophores are designed and synthesized. They are emissive in solid state with colour range from orange to NIR region. Furthermore, they are AIE-active and some of them may contain hybridized local and charge transfer (HLCT) excited state to achieve highly efficient emission upon solvatochromic investigation. Some bis-cyanostyryl thiophenes are fabricated in OLED devices show deep-red to NIR emission, indicative of a promising way to design solid-state NIR-emissive compounds using bis-cyanostyryl derivatives.;Finally, Chapter 6 and 7 present the concluding remarks and the experimental details of the work in Chapters 2 to 5, respectively.
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Lau, Wai Sum. "Synthesis, characterization and application studies of cyanostilbene-based molecular materials with aggregation-induced emission (AIE) characteristics." HKBU Institutional Repository, 2014. https://repository.hkbu.edu.hk/etd_oa/70.
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The molecular design, synthesis, spectroscopic and photophysical characterization of a series of cyanostilbene-based compounds are studied in this thesis. The thermal, electrochemical and aggregation induced emission (AIE) properties of these cyanostilbene-based compounds, as well as their application in organic lighting-emitting diodes, live cell imaging, chemical vapor sensor were investigated. Chapter 1 gives a brief introduction on the aggregation-caused quenching (ACQ) behavior of the conventional organic luminogens and the discovery and proposed mechanism of AIE phenomenon. Furthermore, some examples and the applications of these AIE compounds will be discussed. In Chapter 2, triphenylamine- and carbazole-containing cyanostilbene-based derivatives are presented. From the examination of the emission profile, they are all AIE-active through comparison of the photoluminescence intensity in dissolved and in aggregated states. Additionally, the calculation of the enhancement ratio (I/I0 – 1) of each fluorophore was performed in order to quantify its AIE effect. One of our cyanostilbene-based luminogens has achieved an enhancement ratio with a value of 1128. This cyanostilbene-based luminogens has also shown good performance in OLED investigation. In addition to the OLEDs application, the selected cyanostilbene-based luminogens with solid-state emission, cell-permeability and reversible switch-on/off capability have illustrated the positive result in live-cell imaging and chemical vapor sensing. Conjugated polymer with high molecular weight is the superior option by overcoming the weaknesses of low-molecular-weight luminogens with excellent thin-film form ability and comparatively simple and inexpensive fabrication processes. The design and synthesis of the cyanostilbene-based polymeric chromophores are described in Chapter 3. The polymerization of the AIE-active diacetylene ligands by connection of trans-[Pt(PBu3)2] unit at both ends has successfully retained their AIE behavior. In contrast, the ACQ problem has occurred on the polymers with organic spacers and the AIE-active ligands. From the DFT calculation on the Pt polymers and the blue shift of emission spectra in high water content suggested that the AIE phenomenon of Pt polymers is probably originated from the elimination of the non-radiative intramolecular charge transfer (ICT) process. Owing to the high demand in red-emitting materials in the applications of electroluminescent devices, fluorescent sensing and bio-imaging, effort has been made to design a system with the new chromophores with donor (D) – acceptor (A) system and thus to synthesize phenothiazine (D)-containing cyanostilbene (A)-based derivatives which are depicted in Chapter 4. Consistent with the conventional AIE-active luminogens with a successively climb of photoluminescence intensities in response to the increase of water proportion, phenothiazine-containing cyanostilbene-based derivatives has exhibited a V-shape fashion of emission intensity. It suggests that the emission of chromophores started to be quenched due to the increase of solvent polarity, overriding that of the molecular aggregation when a “small” volume of water is being introduced. While aggregate formation was dominant from the addition of a “large” amount of poor solvent, less polar local environment was created which suppressed the non-radiative transition to the ICT state and intensified the emission efficiency. Phenothiazine (D) – cyanostilbene (A) system has created a series of red-emitting chromophores with great tunability for the sake of achieving the desired emission color and better emission efficiency. To functionalize these AIE-active cyanostilbene-based chromophores, pyridine group was attached to the compounds to take the advantage of its metal-chelating capability, which is discussed in Chapter 5. The AIE features of cyanostilbene-based compounds can be preserved after the introduction of the pyridyl unit. Even it possessed a weak photoluminescence in its dilute solution which suggest that the high electron delocalization within the molecule has rigidified the structure to some extent, it is transformed to a highly emissive state with a high proportion of water. The exclusive variation of emission behavior with obvious bathochromic shift and boost of emission spectrum in the presence of cadmium-(II) ion has demonstrated its potential metal ion sensing ability. Chapter 6 and 7 present the concluding remarks and the experimental data of the compounds of Chapter 2 to 5, respectively.
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Dong, Lei. "Conception et synthèse de glyco-sondes fluorescentes pour des applications en détection." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1153/document.
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Avec le progrès scientifique et les besoins sociétaux, diverses méthodes de détection spécifiques et sensibles des métaux, des protéines et d’autres biomolécules sont largement utilisées dans la protection de l’environnement, la surveillance des maladies, la pharmacothérapie, la production agricole, l’industrie et d’autres domaines importants. Les sondes fluorescentes sont largement développées sur la base des phénomènes de transfert d’énergie (ICT, PET, FRET) et appliquées par exemple à la détection de contaminants ou à l'imagerie cellulaire. Mais l’effet d’agrégation (ACQ) atténue généralement l’intensité de la fluorescence et limite ainsi les applications de sondes organiques (souvent peu solubles dans l’eau) dans l’imagerie cellulaire et les systèmes vivants. Par conséquent, le concept d'« agregated induced emission » (AIE) représente une solution à ces problèmes d’agrégation et plusieurs glycoclusters, glyco-sondes et glyco-complexes fluorescents ont été conçus et reportés pour des applications en analyse biologique. Notre premier projet visait à concevoir et à synthétiser des glyco-polymères fluorescents pour le ciblage cellulaire et l’adressage de médicaments, tandis que la fluorescence permettrait la détection des cellules ciblées. Pour surmonter l'effet ACQ et les interférences provenant de la fluorescence biologique naturelle, nous avons conjugué le dicyanométhylène-4H-pyrane (DCM) et le tétraphényléthène (TPE) afin d'obtenir des sondes fluorescentes (AIE) émettant dans le proche infrarouge. Les glycosides ont fourni une bonne solubilité dans l'eau et l'auto-assemblage a conduit à des systèmes de détection et à une imagerie des cellules cancéreuses. Les glyco-polymères à base de TPE ont été synthétisés à partir de monomères de TPE incorporant deux monosaccharides par conjugaison azide-alcyne (CuAAC) et ces monomères ont été polymérisés par des réactions de CuAAC ou thiol-ène. Les glyco-polymères à base de TPE ne présentaient malheureusement pas une assez grande longueur de chaîne (généralement moins de 7 unités) et les propriétés fluorescentes attendues ne pouvaient donc pas être atteintes. Nous avons ensuite conçu et synthétisé des glyco-dots auto-assemblés par des sondes DCM et des glycoclusters à base de TPE. Les glyco-dots ont présenté une hydrosolubilité élevée et une réponse sélective au peroxynitrite (ONOO-) à la fois in vitro et dans des analyses cellulaires. Les glyco-dots pourraient détecter ONOO- endogène et exogène, mais sans reconnaissance cellulaire spécifique. Nous avons conçu et synthétisé des sondes fluorescentes AIE pouvant s'auto-assembler avec des glycoclusters à base de TPE. Les glyco-dots résultants étaient facilement solubles dans l'eau et présentaient une sensibilité et une sélectivité excellentes pour la détection du thiophénol in vitro et dans des échantillons d'eau environnementaux.Nous avons finalement combiné les deux fragments TPE et DCM pour synthétiser un nouveau fluorophore AIE (TPE-DCM) avec émission à longue longueur d'onde. Ensuite, la conjugaison avec des glycosides par CuAAC a conduit à des sondes AIE fluorescentes à émission de longue longueur d'onde, avec une excellente solubilité dans l'eau. Une application à la détection de glycosidases in vitro et dans des dosages cellulaires ou sur des modèles animaux a été possible avec ces sondesWith scientific and social progress, various methods for the specific and sensitive detection of metals, proteins and other biomolecules are widely utilized in environmental protection, disease surveillance, drug therapy, agricultural production, industry and other significant areas. Fluorescent probes are widely developed based on ICT, PET, FRET and other fluorescence mechanisms, and applied to the detection of contaminants or in cell imaging. But the ACQ effect usually quenched the fluorescence intensity and thus limited the applications of organic probes in cell imaging and living systems. Therefore, the concept of aggregated-induced emission (AIE) appears as a possible solution to these problems and several fluorescent glycoclusters, glyco-probes and glyco-complexes were designed and reported for biological analysis. Our first project aimed to design and synthesize fluorescent glyco-polymers with multiple glycosides for cell targeting and drug delivery while fluorescence will allow the detection of the targeted cells. To overcome the ACQ effect and interference from natural biological background fluorescence, we conjugated dicyanomethylene-4H-pyran (DCM) and tetraphenylethene (TPE) to obtain near-infrared AIE fluorescent probes. The glycosides provided good water solubility and self-assembly in water led to detection systems and imaging cancer cells. TPE-based glycopolymers were synthesized from TPE monomers incorporating two monosaccharides by CuAAC conjugation and these monomers were polymerized by either CuAAC or thiol-ene “click” reactions. The TPE-based glycopolymers did not display a large chain length (typically less than 7 units) and the expected fluorescent properties could not be reached. We then designed and synthesized glyco-dots self-assembled by DCM probes and TPE-based glycoclusters. The glyco-dots displayed high water-solubility and selective response to peroxynitrite (ONOO-) both in vitro and in cell assays. The glyco-dots could detect endogenous and exogenous ONOO- but no specific cell recognition. We designed and synthesized AIE fluorescent probes which could self-assemble with TPE-based glycoclusters. The resulting glyco-dots were readily water soluble and displayed excellent sensitivity and selectivity for thiophenol detection in vitro and in environmental water samples. We finally combined both TPE and DCM moieties to synthesize a novel AIE fluorophore (TPE-DCM) with long-wavelength emission. Then conjugation with glycosides through CuAAC led to AIE fluorescent probes with long-wavelength emission, excellent water-solubility. Application to the detection of glycosidases in vitro and in cell assays or animal models was possible with these probes
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Yu, Tingting. "Solid state luminescent molecules, macromolecules and materials, their response to stimuli and their applications in devices." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEN061.
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Au cours de cette thèse, nous avons développé de nouveaux chromophores conjugués luminescents présentant une alternance de groupements donneurs et accepteurs, avec une attention particulière quant à leurs propriétés d’émission dans le rouge et proche infra-rouge à l’état solide ou agrégats. Nous avons étudié l’influence de la longueur de chaine et de la nature de la substitution donneur/accepteur non seulement sur les propriétés optiques en solution mais aussi (et surtout) sur le matériau agrégé. Enfin, en utilisant les propriétés spécifiques de certains des composés développés selon cette approche, nous avons exploré leur potentiel pour des applications allant de matériaux fluorochrome stimuli-responsifs (sous forme de films) à l’élaboration de sondes à deux photons émettant dans le proche infra rouge pour l’imagerie biologique. Les principaux accomplissements de cette thèse sont les suivant: 1/ de nouveaux polymères alternant des motifs triarylamine (ou carbazole)/ tetraphenylethylene (TPE) dans leur chaine principale ont été synthétisés. Leurs propriétés d’émission à l’état solide présentent des caractéristiques d’agrégats-J, peu courant dans les dérivés TPE, ce que nous attribuons à l’arrangement linéaire des chaînes polymères; 2/ Une nouvelle famille de colorants diphenylamine/benzobisthiazole et leurs dérivés oligomères ont été synthétisés. Leurs propriétés de luminescence présentent une sensibilité marquée à la protonation, que nous avons utilisée dans la conceptions de dispositifs luminescents commutables par stimuli acide/base; 3/Nous avons exploré la possibilité d’introduire des modifications chimiques complémentaires sur cette nouvelle famille de chromophores, afin d’obtenir des composés luminescents à l’état solide dans le proche infrarouge, en particulier par un changement de la nature de la transition électronique à transfert de charge intramoléculaire vers une transition cyanine, par le biais d’une quaternarisation des fonction benzobisthiazole. D’autres modifications ont conduit à une amélioration de la biocompatibilté des molécules, de leurs propriétés AIE, ou encore de leur spécificité de marquage cellulaire; 4/ Ces nouveaux composés présentent une luminescence photo-commutable (de type allumé/éteint), qui pourrait présenter un intérêt dans l’élaboration d’agents de contraste pour l’imagerie de microscopie super-résolueIn this thesis, we developed new luminescent conjugated chromophores presenting an alternation of electron donor and acceptor groups, with a specific focus on their emission properties in aggregates or solid states in far-red or near infrared region. We studied the influence of chain length and donor/acceptor substitution not only on the optical properties of the isolated compounds, but also (and especially) on the material in its aggregated state. Finally, taking advantages of these specific properties of some of the as-designed candidates, we explored their potential applications ranging from fluorochromic stimuli-responsive sensors (in film form) to red and NIR luminescent two-photon probes for biological imaging. The main achievements of this thesis are the following: 1) new alternating triarylamine or carbazole / tetraphenylethylene (TPE) polymers were synthesized. Their solid state luminescence poseeses typical J-aggregates emission features in solid state, unusual in TPE derivatives that we relate to the linear polymeric nature of the object; 2) A new family of diphenylamine / benzobisthiazole chromophores and derived oligomers were synthesized . Their luminescence properties present a marked sensitivity to protonation, which we took advantage of in the making of acid-base responsive luminescent devices; 3) we explored the possibility of additional chemical transformations of the newly designed chromophore, in order to achieve solid state NIR emission, in particular by means of a change in the character of the electronic transition from Intra-Molecular Charge Tranfer (ICT) to Cyanine transition owing to benzothiazole quaternarization. Other modifications resulted in improvement of their AIE properties, bioavailability and selectivity of their cellular compartments staining ability; 4) These new compounds present a reversible photoinduced “on-off” switching of their luminescence properties, which might present an interest in the design of contrast-agents for super resolution imaging
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Dong, Yujie. "Synthesis, photophysical properties and applications of aggregation-induced emission materials based on cyanostilbene moiety." HKBU Institutional Repository, 2016. https://repository.hkbu.edu.hk/etd_oa/313.
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The concept of "aggregation-induced emission" (AIE) effect has induced a great deal of attention these days. Now, exploration of new AIE-active molecular system and multiple high technique applications for AIE materials are the two research hotspots. Cyanostilbene, as a classical structural unit in photoelectric functional materials, also exhibited this unique luminescence behavior. The research background was illustrated in Chapter 1, which mainly introduced the development of this subject. In this project, Chapter 2 and Chapter 3 presented two classes of functionalized AIE-active molecules based on cyanostilbene moiety, and their applications were investigated, while Chapter 4 demonstrated a series of donor-acceptor (D-A) molecules with highly emissive unit, and their photophysical properties were studied.;In Chapter 2, four different donor-substituted cyanostilbene-based dipyrrins were synthesized and characterized. The investigation of photophysical properties confirms that these molecules are AIE-active, which should be attributed to the cyanostilbene moiety. The introduction of different donor groups showed little impact on their luminescence. Furthermore, the emission properties of these molecules were found to be sensitive to Zn2+, that is, addition of Zn2+ enormously enhanced its fluorescence in THF. The titration experiments proved they showed good selectivity and sensitivity for Zn2+ detection with relatively low limit of detection. Job's curve and spectral studies of their corresponding zinc complex indicated that the ratio for dipyrrins and Zn2+ is 2:1, which suggested the formation of zinc complex by chelation-enhanced fluorescence (CHEF) effect should be the reason of the enhanced fluorescence. By combining dipyrrin with typical AIE-active moiety tetraphenylethylene (TPE), an AIE-active TPE-based dipyrrin was prepared. The studies of its fluorogenic Zn2+ detection confirmed that the CHEF effect together with AIE effect are responsible for the intense fluorescence, indicating the potential application as a Zn2+ detector in aqueous media.;In Chapter 3, the cyanostilbene backbone was functionalized with a terpyridine unit to construct four terpyridine-based cyanostilbene molecules with different donor substitutents. The investigation of their photophysical properties confirms that they are AIEE-active. With the effect of different electron-donating groups, their solid-state fluorescence color was adjusted from blue to orange-red successfully. According to the calculation results of their frontier molecular orbitals, terpyridine has little impacts on their luminescence, but would influence their solid-state emission obviously owing to its large steric hindrance. This class of molecules displayed higher luminescence efficiency in solid state than in their dissolved state. The twisted molecular conformation in single crystal, which effectively avoids close π-π stacking, was assumed to be responsible for the high luminescence efficiency in solid state. This kind of molecules show distinct switched fluorescence by stimuli of acid/base vapors, and this phenomenon derives from the protonation effect of nitrogen atoms in the terpyridine unit. Moreover, three of these molecules exhibit good electroluminescence properties. Especially, the crystal of non-donor substituted molecule show amplified spontaneous emission (ASE) properties, indicating this blue-emissive material can be used in multiple areas such as chemical sensor, organic light emitting diodes (OLEDs) and organic laser media.
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Ohtani, Shunsuke. "Creation of Emissive and Functional Materials Based on Fused-Boron Complexes." Kyoto University, 2021. http://hdl.handle.net/2433/261618.
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Ito, Shunichiro. "Synthesis and Photophysical Properties of Functional Luminescent Materials Based on β-Diiminate Complexes Composed of Main-Group Metals." Doctoral thesis, Kyoto University, 2020. http://hdl.handle.net/2433/245840.
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京都大学0048
新制・課程博士
博士(工学)
甲第22155号
工博第4659号
新制||工||1727(附属図書館)
京都大学大学院工学研究科高分子化学専攻
(主査)教授 田中 一生, 教授 秋吉 一成, 教授 古賀 毅
学位規則第4条第1項該当
Doctor of Philosophy (Engineering)
Kyoto University
DGAM
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Suenaga, Kazumasa. "Precise Control of Highly-Efficient Solid-Emissive Property of Boron Ketoiminate." Kyoto University, 2019. http://hdl.handle.net/2433/242531.
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付記する学位プログラム名: 充実した健康長寿社会を築く総合医療開発リーダー育成プログラムKyoto University (京都大学)
0048
新制・課程博士
博士(工学)
甲第21793号
工博第4610号
新制||工||1718(附属図書館)
京都大学大学院工学研究科高分子化学専攻
(主査)教授 田中 一生, 教授 秋吉 一成, 教授 大内 誠
学位規則第4条第1項該当
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Arribat, Mathieu. "Acides aminés phosphole ou silole : vers de nouvelles sondes fluorescentes pour un marquage de peptide innovant." Thesis, Montpellier, 2018. http://www.theses.fr/2018MONTS144.
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La première partie de ces travaux de thèse concerne la synthèse d’acides aminés phosphole par formation d’une liaison P-C. Les propriétés de fluorescence (absorption, émission et rendement quantique) sont modulées à la fois par les différents substituants présents sur le phosphore (BH3, O, S…) ainsi que par le squelette aromatique du phosphole. Des couplages peptidiques modèles réalisés en solution et sur support solide démontrent la possibilité d’intégrer ces acides aminés dans des peptides d’intérêts. La deuxième partie concerne la synthèse de nouveaux phospholes fonctionnalisés ainsi que d’une nouvelle méthode d’accrochage pour les introduire sur différents groupes pendants (SH, NH2, OH) d’acide aminés et peptides via la formation de liaisons P-S, P-N ou P-O. La troisième partie de ce travail a consisté en la synthèse d’une nouvelle classe d’acides aminés tétraphénylsilole fluorescents qui présentent des propriétés d’AIE (aggregation-induced emission) et pourront être utilisés pour le marquage de peptides d’intérêtsThe first part of this work is focused on phospholyl amino acids synthesis by formation of a P-C bond. The fluorescent properties (absorption, emission and quantum yield) are modulated either by the substituent on the phosphorus atom (BH3, O, S, …) or by the aromatic skeleton of the phosphole. Peptide coupling in solution or on solid support were performed and showed the possibility to introduce such amino acids into peptide of interest. The second part of this work is dedicated to the synthesis of new functionalized phospholes for a chemoselective grafting on amino acid and peptides pendant groups (SH, NH2, OH) via PS, P-N or P-O bonds. The third part consists into the synthesis of a new class of tetraphenylsilole amino acids which exhibit AIE (aggregation-induced emission) fluorescent properties. Those compounds were successfully incorporated into di- an tri- peptides in solution and on solid support
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Dong, Wenyue [Verfasser]. "The Design and Synthesis of Conjugated Polymers with Aggregation-Induced Emission and Their Application in Fluorescence Sensing / Wenyue Dong." Wuppertal : Universitätsbibliothek Wuppertal, 2015. http://d-nb.info/1076929885/34.
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Tominaga, Masato. "Functional π-Conjugated Materials Based on Structure of o-Carborane." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188607.
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Upamali, Karasinghe A. Nadeeka. "Carbazole-Based, Self-Assembled, Π-Conjugated Systems As Fluorescent Micro And Nanomaterials - Synthesis, Photophysical Properties, Emission Enhancement And Chemical Sensing." Bowling Green State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1323099511.
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Zhang, Wanying. "Comprehensive Study on Fluorescent ESIPT Liquid Crystal Materials and the Potential for Optoelectronic Applications." Doctoral thesis, Kyoto University, 2021. http://hdl.handle.net/2433/263621.
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Yoshii, Ryosuke. "Synthesis of Highly-Functional Polymers Using Characteristics of Four-Coordinated Boron-Complexes with Boron-Nitrogen Bonds." 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/188610.
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Grolleau, Jérémie. "Synthèse de nouveaux semi-conducteurs organiques par arylation directe." Thesis, Angers, 2016. http://www.theses.fr/2016ANGE0029/document.
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Les recherches sur le photovoltaïque organique depuis une dizaine d’année ont permis une constante progression de l’efficacité des cellules solaires. Plusieurs groupes de recherche ont amorcé une réflexion sur les procédés de synthèse qui permettraient de limiter les déchets. Ainsi le couplage par arylation directe qui évite l’utilisation de dérivés organométalliques a émergé comme alternative au couplage organométallique classique. Une première partie est consacrée à l’étude méthodologique du couplage par arylation directe de la triphénylamine avec des dérivés du thiophène-2- carboxaldéhyde substitués en C3 et C4 par des groupements électro-accepteurs et électro-donneurs. Ce motif de base permet l’accès à trois séries de petites molécules par simple condensation. Des cellules photovoltaïques atteignant des rendements de photo-conversion de 3% en cellules bicouches, ont été obtenues. Dans une deuxième partie, la polymérisation par arylation directe sur des monomères du thiophène substitué par des groupements nitriles comme accepteur et des groupements alcoxy ou thioalkyl comme donneur conduit en une seule étape à une nouvelle famille de polymères conjugués. Ces polymères ont été utilisés comme matériaux donneurs et accepteur dans des cellules. Enfin en dernière partie, un travail exploratoire sur les propriétés d’émission de dérivés du benzofurane a été entrepris. Des réactions de condensation de Knoevenagel ont été développées pour obtenir toute une série de dérivés contenant l’unité cyano-vinylbenzofurane. La plupart des composés présente une forte émission à l’état solideResearch on organic photovoltaics over a decade allowed a steadily increasing in the efficiency of solar cells. Several research groups have begun a reflection on the synthesis processes to limit wastes. Thus the direct arylation coupling which avoids the use of organometallic compounds, has emerged as an example of green reaction. The first part is devoted to the methodological study of direct arylation of bromotriphenylamine with thiophene-2-carboxaldehyde derivatives substituted in C3 and C4 by electron-withdrawing groups and electron-donor groups. This basic pattern allows access to three small molecules by condensation. Photovoltaic cells reaching photoconversion efficiencies of 3% were obtained. In the second part, the polymerization by direct arylation of sustituted thiophene monomers by nitrile groups as the acceptor and by alkoxy or thioalkyl as the donor led in one step to a novel family of conjugated polymers having donor and acceptor groups alternately. Solar cells were made with the polymers as donors or as acceptors materials. Finally, in the last part, exploratory work on the emission properties of benzofuran derivatives have been made. Knoevenagel condensations have been developed for a range of compounds containing the cyano-vinylbenzofuran unit. Most compounds have high emission in the solid state
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Cousins, Morgan. "I. Designing Brighter Fluorophores: A Computational And Spectroscopic Approach To Predicting Photophysical Properties Of Hydrazone-Based Dyes Ii. Developing Spectroscopic Methods To Better Understand The Cofactors Of Metalloproteins." ScholarWorks @ UVM, 2017. https://scholarworks.uvm.edu/graddis/787.
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Luminogens are molecules that emit light upon exposure to high-energy light, and fluorophores are one class of luminogens. Applications of fluorophores range from microviscosity sensors to light emitting diodes (LEDs), as well as biosensors, just to name a few. Many of these applications require the fluorophore to be in the aggregate or solid state. Some fluorophores become highly emissive in the aggregate state; these fluorophores are aggregation-induced emission (AIE) luminogens. Currently, very few quantum mechanical mechanisms have been proposed to describe the unique AIE behavior of luminogens.
Boron difluorohydrazone (BODIHY) dyes are a new type of AIE fluorophore. The bright emission is from the S>1 excited state (“anomalous” emission) contrary to Kasha’s Rule. Thus, the mechanism Suppression of Kasha’s Rule (SOKR) was proposed to be responsible for the family of BODIHY dyes. We hypothesize that the SOKR mechanism can explain AIE as well as the anomalous emission of other fluorophores. New BODIHY derivatives (para-CO2H BODIHY, aluminum difluorohydrazone (ALDIHY), and paranitro ALDIHY) were predicted to be bright anomalous fluorophores through density functional theory (DFT) and time-dependent DFT (TDDFT) investigations. In addition, a series of anomalous fluorophores were investigated to determine if their photophysical properties could be explained by the SOKR mechanism (azulene, 1,6-diphenyl-1,3,5hexatriene, and zinc tetraphenylporphyrin). Finally, several triazolopyridinium and triazoloquinolinium dyes were computationally investigated by DFT and TDDFT calculations, and an accurate computational model for the large Stokes shifts of these dyes was developed. In conclusion, a better understanding of the photophysical properties through DFT and TDDFT modeling and spectroscopic investigation of hydrazone-based fluorophores has been achieved.
In addition, the metal active sites and cofactors of metalloproteins were probed by optical spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and DFT modeling. In conjunction, these techniques can be used to elucidate the electronic structure responsible for the unique function of these metalloproteins. Specifically, a novel ironsulfur cluster of a metalloprotein that may be involved in endospore formation of Clostridium difficile, CotA, was characterized by magnetic circular dichroism (MCD) spectroscopy. We propose that CotA contains a high-spin [4Fe-4S] cluster and a Rieske [2Fe-2S] cluster. It appears that the multimerization of the protein is related to the cluster conversion at the interface of monomeric subunits where two [2Fe-2S] clusters combine to form the [4Fe-4S] cluster. In addition, a putative cobalamin acquisition protein from Phaeodactylum tricornutum, CBA1, was not expressed at sufficient concentrations in Escherichia coli for spectroscopic investigation. Finally, a new technique was developed using cobalt-59 NMR spectroscopy to better understand the nucleophilic character of cobalt tetrapyrroles, such as cobalamin (vitamin B12), as biological cofactors as well as synthetic catalysts. New insight into the electronic structure provides valuable information related to the mechanism of these metalloproteins.
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Xie, Sheng. "Perfluroaryl azides : Reactivities, Unique Reactions and their Applications in the Synthesis of Theranostic Agents." Doctoral thesis, KTH, Organisk kemi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-172950.
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The work centersaround perfluoroaryl azides (PFAAs), and theirability to undergo certain fast and robusttransformations. The chemistry was furtherappliedfor biomedical applications. The first section focuses on the azide-aldehyde-amine cycloaddition using PFAAs. Experimental and computational investigations uncovered a fast azide-enamine cycloaddition to form triazolines, which spontaneously rearrange into stable amidine products. In addition, this transformation was explored in the formulation of pure nanodrugs. Because this reaction can introduce a phenyl and a perfluoroaryl moiety enabling supramolecular interactions near the antibiotic drug, the resulting ciprofloxacin derivatives formed nano-sized aggregates by precipitation, which displayed aggregation-induced emission for bacterial imaging as well as enhanced size-dependent antibacterial efficacy. In the second section, the high electrophilicity of PFAAs was explored to transform azides to aryl amides. The reactivity of PFAAs in the thioacid/azide reaction was studied. In addition, PFAAs were discovered to react with phenylacetaldehyde to form aryl amidesviaan azide-enol cycloaddition, similar tothe perfluoroaryl azide-aldehyde-amine reaction.This strategyof amide synthesiswas furthermoregeneralized through a combination of base-catalyzed azide-enolate cycloaddition reaction and acid-or heat-promoted rearrangement of triazolines. The last section describes a type of azide fluorogens whose fluorescence can be switched on by alight-initiated intramolecular nitrene insertion intoa C-H bond in the neighboring aromaticring. These fluorogenic structures were efficiently accessed via the direct nucleophilic aromatic substitution of PFAAs.QC 20150903
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Rouillon, Jean. "Chromophores présentant une émission à l'état solide induite à deux photons : synthèses et études de la dynamique des états excités en solution et en agrégats." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEN057.
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La conception de nano-objets biocompatibles pouvant être utilisés en microscopie à fluorescence présente un intérêt majeur. Dans cette optique, des chromophores ayant des structures leurs permettant d’une part, d’être actifs en absorption deux photons (A2P) et d’autre part, d’avoir une émission induite par l’agrégation (AIE), ont été synthétisés autour d’une base tétraphényléthylène (TPE) étendue. L’étude de l’influence de la stéréoconfiguration (Z ou E) de cette famille de molécules sur leurs auto-assemblage nous a permis d’établir un lien entre cristallinité et fluorescence des agrégats, et d’élaborer un nano-objet optimisé pour des applications d’imagerie in vitro et in vivo par microscopie de fluorescence à deux photons.Les mécanismes à l’origine des propriétés d’AIE des TPE, toujours débattus dans la littérature, ont pu être rationalisés par une étude photophysique détaillée rendue possible par l’élaboration d’une nouvelle méthode de RMN actinométrique. La fonctionnalisation d’un des chromophores par un bloc polymère hydrophile conduisant à un auto-assemblage sous forme micellaire en milieu aqueux a permis l’obtention de nano-objets luminescents d’un type nouveau, qui ont été utilisés comme sondes spécifique de l’ADN. Enfin, une nouvelle méthodologie de synthèse stéréosélective d’AIEgènes de la famille des ditriazolostilbène (DTS) a été proposée, ouvrant la voie à une ingénierie moléculaire polyvalente basée sur la cycloaddition azoture-alcyneThe design of biocompatible nano-objects used in fluorescence microscopy represents a major interest. In this perspective, chromophores with two-photon absorption (A2P) and aggregation induced emission (AIE) properties have been synthesized, derived from an extended tetraphenylethylene (TPE) base. The study of the influence of the stereoconfiguration (Z or E) of this family of molecules on their self-assembly established a link between crystallinity and fluorescence of the aggregates, and nano-objects were optimized for in vitro and in vivo imaging applications by two-photon fluorescence microscopy.The mechanisms behind the AIE properties of TPEs, still debated in the literature, have been rationalized by a detailed photophysical study made possible by the development of a new actinometric NMR method. The functionalization of one of the chromophores by a hydrophilic polymer block leading to a self-assembly in micellar form in aqueous medium was done to obtain luminescent nano-objects of a new type, which have been used as DNA specific probes. Finally, a new methodology for the stereoselective synthesis of AIEgens of the ditriazolostilbene (DTS) family was proposed, paving the way for versatile molecular engineering based on azide-alkyne cycloaddition
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Castro, Jessica Julieth. "Luminogènes-AIE à base de ligands hydroxyamidines : synthèse, caractérisation et application comme pigments pour dispositifs." Thèse, 2018. http://hdl.handle.net/1866/21930.
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Lin, Li-yang, and 林利陽. "Polypeptides containing luminescent units with aggregation-induced emission property." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/j25965.
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碩士國立中山大學
材料與光電科學學系研究所
103
First chapter: Tetraphenylthiophene (TP) with aggregation-enhanced emission (AEE) property was used as terminal fluorophore of the water-soluble poly(γ-propargyl-L-glutamate) (PPLG)-based polymers of TP-PPLG-g-MEO2. In this study, we research various TP-PPLG-g-MEO2 affect aggregation of luminescence. In water, when concentration of TP-PPLG-g-MEO2 achieve CMC, TP-PPLG-g-MEO2 will aggregation to nanoparticle and suddenly increasing emission, and when heating over LCST, TP-PPLG-g-MEO2 will contract and also enhance emission. We use TP-PPLG-g-MEO2 “salt out effect” property to probe salt in water, salt have interaction with side chain MEO2 and peptide main chain to make TP-PPLG-g-MEO2 contract together and change secondary structure to b-sheet conformation to enhance emission. In the strong alkaline media, TP-PPLG-g-MEO2 backbone change to random coil conformation that break intramolecular hydrogen bonding and loss LCST property, TP-PPLG-g-MEO2 become is a micelle like structure, core was hydrophobic TP and shell was hydrophilic polypeptide and particle size about 500nm measure by DLS. In random coil conformation, chain end hydrophobic TP have strong aggregation than in the a-helical and have strong aggregation emission peak. At last, we use TP-PPLG-g-MEO2 to detect BSA. When TP-PPLG-g-MEO2 mixture with BSA, TP-PPLG-g-MEO2 will fall in to BSA and separate to decrease TP-PPLG-g-MEO2 aggregation and emission. Second chapter: We synthesis polypeptide contain TPA pendent by click reaction. The resulting PPLG-g-TPA contains the crystalline TPA side groups, Tm about 145 oC and is therefore high Tg materials with the desired AIE activity. Due to side chain TPA, PPLG-g-TPA have piezofluorochromic property that have two color between crystal and amorphous state. The lone pair electrons of nitrogen atom in TPA side groups inherit PPLG-g-TPA the sensitivity toward acid HCl and metal ions. Emission of PPLG-g-TPA was progressively decreased upon increasing the amounts of HCl and metal ions in the solutions that can be acid or metal ions sensor.
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Chang, Jui-Wen, and 張瑞文. "Aggregation-Induced Emission Characteristics of Tetraphenylethene-Capped Dipeptide Materials." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/43nzds.
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碩士國立交通大學
材料科學與工程學系所
103
Supramolecular self-assembly hydrogel materials is ubiquitous in materials science and biology. Self-assembly provides routes to a range of materials with regular structures. And others advantages to developed in this process. In this thesis, we developed the novel dipeptide supramolecular hydrogel with self-assembly gelation enhanced fluorescence emission. Tetraphenylethene (TPE) is almost non-emissive when molecularly dissolved in solution but turns to be highly fluorescent in aggregate states. The hydrogelator was constructed by using the TPE as the hydrophobic part and four different dipeptide (Gly-Gly、 Ser-Ser、 Asp-Asp and Tyr-Asp) as the hydrophilic component. We investigated these amphiphilic low-moleculars weight of the gelation pH value, performance of rheology, morphology and optical properties of the AIE characteristics. Each of the luminophore hydrogels has received different interesting results: TPE-GG is the minimum molecular weight of TPE-capped peptide forms the supramolecular hydrogel. TPE-SS is the minimum molecular weight of TPE-capped peptide forms the supramolecular hydrogel under neutral condition. TPE-DD could form the hydrogel under the acid condition(pH value= 4.3) and could be a pH sensor. TPE-YD can form the strongest hydrgel under the acid condition(pH value= 4.3) and also can form stable hydrgel under neutral condition. TPE-SS and TPE-YD can form hydrogel under neutral condition. These materials are potentially useful for develop 3D cell culture in the future. TPE-DD could change the emission properties under different pH values, which may be promising a biomaterial as an active element of biosensors.
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Chen, Jyun-Wei, and 陳俊瑋. "Novel Aggregation-Induced Emission Fluorophores Applied on Cellular Studies." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/88facz.
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博士國立中興大學
化學工程學系所
106
In this study, we focused on developing the newly organic molecules on the therapy and diagnosis of cancers. In the experiments, we synthesized some simple fluorescent organic molecules and enhanced their performances in the cells by the unique properties of Aggregation-Induced Emission (AIE). First, we synthesized an asymmetric 1, 6-disubstituted naphthalene (NV-12P), which can generate particular reactive oxygen species to undergo type I photodynamic therapy under irradiation. Furthermore, this compound can specifically localize in mitochondria in cancer cells to exhibit selective dark cytotoxicity, and exhibit efficient photodamage in cancer cells due to intracellular bright spots. Results suggested that this compound can be a potential dual-toxic efficacy molecule. Additionally, a water-soluble pH sensor ADA was designed and synthesized based on the molecular design of photo-induced electron transfer (PET) and intramolecular charge transfer (ICT). The fluorescent emission response against a pH value located in the range of 3~6, which is suitable to label intracellular pH dependent microenvironments. Finally, we not only used ADA to identify intracellular pH gradients between different cell lines, but also developed ADA as a fluorescent molecule that labeled normal cells by the unique fluorescence intensity of ADA in normal cells, making it effective as the control group at the time of cancer diagnosis.
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LIN, YUN-RU, and 林韻茹. "Investigation of Aggregation-Induced-Emission Behavior for Tetraphenylethylene-Based Polymer." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/j97wv6.
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碩士逢甲大學
化學工程學系
105
In this study, we successfully synthesized a small molecules with tetraphenylethylene as the basic structure and the correspounding polymer. Two methods were tested when small molecules was synthesized. The product synthesized by McMurry reaction found to be a good method for the synthesis of small molecules. The molecules were polymerized to obtain the corresponding macromolecule materials. Then, the absorption spectra, fluorescence spectra, aggregation-induced emission effect and quantum yield were measured, respectively. The results showed that the absorption and fluorescence peaks of polymer were bathochromic shifted as conjugation chain was increased. The size of the polymer gradually increased with the increasing of the water fraction of solvent and begins to decrease after the water fraction reach 70% water percentage. The result agrees with the fact that the smaller size particle favor closer packing of polymer molecules and showed brighter fluorescence. In the polymer systems, the intramolecular rotations of the phenyl rotors are already partly restricted at molecular level due to the steric effect of polymer chains. Finally, the thermal stability was measured, the Td was 380℃, and the polymer showed nice thermal stability.
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CHEN, PIN-RUEI, and 陳品叡. "Aggregation-induced emission in tetrasubstituted tetraphenylethene derivatives: synthesis and characterization." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/kj8s8y.
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碩士逢甲大學
化學工程學系
107
Luminescent materials with aggregation-induced emission (AIE) properties have attracted many people's interest in recent years due to their application in, optoelectronic components, fluorescent probes, chemical sensor, and biosensor. Tetraphenylethene (TPE) is a compound that often used to investigate luminescence properties with significant AIE. In this study, TPE derivatives 9, 14, 15, 16, 18a-d with tetra-substituted structure were successfully synthesized, and their absorption spectra, fluorescence spectra, aggregation-induced luminescence, liquid fluorescence quantum yield and electrochemical properties were studied. Based on the red-shift of absorption and fluorescence spectra for compounds 14, and 15, the conjugation growth was observed. In the aggregation-induced emission test, it was found that the fluorescence intensity increased with decrease of the solution solubility, and red-shift of fluorescence occurred. The compound 14, with Tetramethyl silane (TMS) substituents, showed the highest fluorescence quantum yield (56.7%). Moreover, different alkyl chains led to different fluorescence quantum yield. The oxidation potential of the compounds was determined by cyclic voltammetry and the energy of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) was estimated. The thermal decomposition temperatures of the compounds were above 300oC revealing good thermal stability.
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CHNEG, HAN-HUNG, and 鄭翰鴻. "Synthesis and Analysis of Tetraphenylethylene Derivative Exhibiting Aggregation-Induced Emission Property." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/40917032054723533120.
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碩士逢甲大學
化學工程學系
105
Aggregation-induced emission (AIE) have been widely uesd and developed, such as biotechnology, chemical technology, electrochromic, organic light-emitting diodes, and others. In this work, a AIE-active tetraphenylethylene derivative consist of long carbon chain and bromo group have been successfully synthesized. This compound only faintly emit in solution but show strong emission in aggregated state. The photoluminescence progressively increases during increasing the water content. In the THF/water mixture with 90 % water, the photoluminescence intensity is about 16 times increased if compared to pure THF. On the other hand, we observed that the particles are aggregated in the THF/water mixture with 60 % water. This result can be provided to associate with AIE-active.
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Yang, Deng-Jie, and 楊登傑. "Self-assembly of responsive polymers containing luminogen with aggregation-induced emission property." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/f3ufh6.
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碩士國立中山大學
材料與光電科學學系研究所
103
In chapter 1, tetraphenylthiophenen (TP) with aggregation-emission enhancement (AEE) property is served as terminal fluorophore of poly (acrylic acid) (PAA) based polymer of TP-PAA by atom transfer radical polymerization (ATRP) and hydrolysis reaction to probe the relationship between pH-induced conformation change and the AEE-related emission behavior, and the detection of the bovine serum albumin (BSA) model protein. Intermolecular aggregation of the terminal TP unit in TP-PAA is sterically blocked due to the carboxyl groups of the poly (acrylic acid) were involved in H-bonding, leading to the weak AEE-related fluorescence in the neutral aqueous solution. In contrast, the carboxyl group of the poly (acrylic acid) become deprotonated, leading to a strong electrostatic force limiting the hydrogen bonding and results in the terminal TP units in TP-PAA can easily approach each other to form aggregates with strong the emission intensity in the alkaline aqueous solution; The water-soluble TP-PAA were blended with BSA forming complexes due to hydrophobic interactions shows a sensitive and selective fluorescence enhancement property for protein detection. In chapter 2, as restricted intramolecular rotation (RIR) is the key leading to the aggregation-enhanced emission (AEE) property. We propose that luminogenic unit connecting polymer chains is particularly clumsy in rotation in considering that the bulky polymer chains are effective in hampering the rotational freedom of the luminogenic unit connecting to them. To test this idea, we synthesized tetraphenylthiophenen (TP) with aggregation-emission enhancement (AEE) property is served as central fluorophores of sodium polystyrene sulfonate (PSS) based polymer of TP-PSS. We used PL spectroscopy to study AEE phenomena for TP-PSS in solution/solid state and solvent/nonsolvent pair, respectively; we can use the sulfonate side groups of TP-PSS characteristics containing short-range interactions and ion exchange to detect pH value and remove calcium to achieve water softing.
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Sing-HuaSu and 蘇星華. "Fluorescent Copolymers with Aggregation-Induced Emission: Synthesis, Nanofiber Fabrication and Sensing Applications." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/3xequw.
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碩士國立成功大學
化學工程學系
105
Electrospinning (ES) is a simple and versatile method for manufacturing continuous nanofibers. ES nanofibers with their large surface-to-volume ratio are widely used for various applications. In this study, novel fluorescent ES nanofibers are successfully prepared from random copolymers of poly(NIPAAm-co-NMA-co-(PPS-HEMA)) through free radical polymerization and followed by electrospinning for optical applications. PNIPAAm segments with thermo-responsive properties exhibit a hydrophilic-hydrophobic change as the temperatures varied. PNMA segments with chemically cross-linking moiety stabilize the morphology of nanofibers in the solution after thermal cross-linking. PPS-HEMA segments with aggregation-induced emission (AIE) phenomenon show much weaker emission in a good organic solvent. Upon aggregate formation, the emission of these AIE dyes is induced to increase by the effect of the restricted intramolecular rotation. The morphology of nanofibers before/after cross-linking were observed by Field Emission Scanning Electron Microscopy (FE-SEM). The high surface-to-volume ratio of ES nanofibers enhanced the sensitivity compared with that of spin-coating film. Furthermore, the optical measurements of ES nanofibers were reusable for several times.
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Li, Yi-wei, and 李逸維. "Aggregation-Induced Emission Enhancement of organic and polymeric fluorophores containing 2,4,6-Triphenylpyridine moiety." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/60225039021678798674.
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碩士國立中山大學
材料與光電科學學系研究所
100
In this study, organic and polymeric fluorophores based on 2,4,6-triphenylpyridiene (TPP) structure were found to have the novel aggregation-induced emission enhancement (AIEE) property. For the small-mass fluorophores, TPP and cyano-functionalized TPP (TPP-CN) were prepared from the facile Chichibabin reaction and their AIEE properties were characterized by the emission behavior in solvent/nonsolvent pair. Solid samples of TPP and TPP-CN exhibit enhanced emission with increasing annealing time under solvent vapors, thus, both compounds have the characters of crystallization-induced emission enhancement (CIEE) behavior. For polymeric system, copolymers PTPPF containing alternative TPP and 9,9-dioctylfluorene units were prepared through Suzuki coupling and study on its fluorescence behavior also reveals its AIEE feature. The rigid polymer possesses high emission intensity in its dilute solution state and remains almost unchanged with increasing nonsolvent fraction. The solid sample was found to have a high quantum yield (ФF) of 70 %.
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Chen, Huan-Wen, and 陳煥文. "Synthesis, Identification of Structure, and Fluorescence Characterization of Aggregation-Induced Emission of Materials." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/83768997252549351644.
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碩士國立中央大學
化學學系
102
In this study, we synthesized a serious of fluorophore with various donor and acceptor substituents. The longer emission wavelength fluorophore can be adjusted by molecular design which nonplanar conjugated structure could restrict intramolecular rotation in solid state. Moreover, aggregation-induced emission phenomenon will be found in nonplanar conjugated structure. On the other hand, we added dicyano-substituented with dithiophene fluorophore to test their aggregation-induced emission behavior. In addition, the thermal properties and the energy level of HOMO and LUMO were estimated by thermogravimetric analyzer, differential scanning calorimeter, cyclic voltammetry, and low-energy photoelectron spectrometer, respectively. Finally, the density functional theory and time-dependent density functional theory to imitate the orbital and energy levels of HOMO and LUMO.
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Chien, Rong-hong, and 簡榮宏. "Aggregation-induced emission of organic compounds and polymers containing fluorene or tetraphenylthiophene ring." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/43488579296445205463.
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博士國立中山大學
材料與光電科學學系研究所
99
Traditional organic chromophores and polymers with disc-like, coplanar geometry tend to be highly emissive in the dilute solutions but become weakly luminescent in the concentrated solution and solid states. On the contrast, conventional chromophores (such as silole) with non-coplanar structure exhibit strong fluorescence in the concentrated states due to the aggregation-induced emission (AIE) or AIE enhancement (AIEE) effect originated from the restricted intramolecular rotation (RIR) inherent from the chemical structures of the luminescent materials. To verify the influence of RIR on the AIEE properties, four approaches were attempted in this research. First, copolymers PFN with alternative fluorene-naphthol unit was prepared through facile Suzuki coupling and was characterized to have AIEE properties due to the hydrogen-bond (H-bond) interactions among the inherent hydroxyl (OH) groups of the naphthol units. The H-bond interactions of PFN copolymer effectively restrict the molecular rotations and experimental variables (such as increasing solution concentration, introducing non-solvent water to solution, cooling and applying shearing forces during solvent evaporation stage etc.) effective in promoting the H-bond interactions result in the emission enhancement. Second, the fluorescent PFN was blended with poly(vinyl pyrrolidone) (PVR) through facile hydrogen-bond (H-bond) interactions. By the effective H-bond interactions between the OH groups of PFN and the carbonyl functions of PVR. The molecular rotations of PFN can be effectively locked by large amounts of carbonyl groups in PVR. With the efficient H-bond interactions, the PFN/PVR blend with the low content (2.33 wt%) of fluorescent PFN component actually has a high quantum efficiency of 0.93, comparatively higher than other blends containing higher fluorescent PFN. Third, novel vinyl polymer PTP with pendant AIE-effective tetraphenylthiophene (TP) group was prepared through radical polymerization. The resultant PTP polymer exhibits two discernible emission bands corresponding to monomer and aggregate emissions, respectively. The relative monomer to aggregate emission intensity of the PTP polymer in either the solution or the solid state depends strongly on the extent of aggregations. Increasing solution concentration results in the increasing extent of aggregation and the increasing aggregate/monomer emission ratio and also, the large emission enhancement due to the AIEE effect. Finally, the TP-derived ammonium (TP-NH3+) cations are complexed with poly(sodium vinylsulfonate) (PSV) polyanion to generate ionic PSV-TP(x/y) systems with long-range electrostatic interactions between the cationic ammonium of TP-NH3+ and the polyanion of PSV. The fluorophoric TP units are associated with each other to form large aggregate domains stabilized by the long-range interactions. Introduction of water into dilute solution of PSV-TP in THF resulted in self-aggregated nanoparticles and the accompanied emission enhancement due to AIEE effect. Introduction of excess PSV polyanions promoted the self-aggregation of the TP fluorophores and resulted in the fluorescence enhancement. Nevertheless, addition of NaCl electrolytes causes the dissociations of the TP aggregates and the corresponding emission reduction. By controlling the additive, the blended PSV-TP film containing excess PSV has a high quantum yield of ΦF = 0.83. In addition, the ionic PSV-TP complex film possesses high spectral stability without spectral variations after annealing at a high temperature of 270 oC.
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Lin, Yu-Chun, and 林泑君. "Supramolecular Nanostructures with Aggregation-Induced Emission Characteristics and their Applications in pH Sensors." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/p4vxbc.
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碩士國立交通大學
材料科學與工程學系所
103
In this study, we have synthesized a series of peptide-based low molecular weight hydrogelators. This thesis has two-fold part. In the first part, a new class of organic hydrogelators are developed. These three-dimensional hydrogels contain nanofibrous structures with average widths of ca. 10-12 nm, which prepared via self-assembly of small molecules (PFB-dipeptides) in water. The PFB-dipeptide is weakly fluorescent in solution, but the intensity is increased by almost ~200-fold in the assemblies. The aggregation-induced emission (AIE) in the PFB-dipeptide nanostructures is unusual because there is no AIE-capped moiety in the molecule. The origin of the unusual AIE character is attributed to the side chain steric and hydrophobic effects of amino acids in the structure of PFB-dipeptides and the presence of intermolecular J-type quadruple-quadruple interactions of perfluoropheny-phenyl pairs between the PFB-dipeptides in the assemblies. This work illustrates the importance of the structure-property relationship on the development of new nanoscience and self-assembly nanomaterials. In the second part, a new series of self-assembled peptide nanostructures based on naphthalimide were synthesized and studied, the materials have significant differences in their fluorescence intensity, which have a higher emission peak at acidic conditions. Cell imaging was observed small spherical organelles (lysosomes) in live human prostate cancer PC-3 cell line and significant colocalizations (84.14 ± 2.99 %) of the sensor ppNI-FDGEA with a commercial available Lysotracker Red DND-99 probe by confocal fluorescence microscopy. This design template may also be used to synthesize other functional peptide sequences with potential applications in tissue engineering.
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Huang, Po-Chiao, and 黃柏喬. "Use of cyclodextrin to impose rotational restriction of luminogens with aggregation-induced emission property." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/t7rr7x.
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碩士國立中山大學
材料與光電科學學系研究所
103
In Chapter 1, Because restricted molecular rotation is the main mechanism responsible for the aggregation-induced emission (AIE), a Jeffamine-included polyrotaxane (JCD) was therefore used in this study as rigid template to impose effective rotational restriction on the AIE-active luminogen of 1,2-bis(2,4-dihydroxybenzylidene)hydrazine (CN4OH). Besides rigidifying the flexible Jeffamine chain, the β-cyclodextrin (β-CD) rings of JCD also provided hydroxyl (OH) groups to hydrogen bond to the OHs of CN4OH, furnishing emissive CN4OH/JCD(x/y) (x/y: molar ratio between CN4OH and JCD) blends with emission efficiency higher than the pure CN4OH itself. Dependent on the composition of the blends, CN4OHs in the blends are arrayed differently to experience varied levels of rotational restriction and thus emit with an intensity correlated with molecular arrangement of the CN4OHs in the blends. The relationship between molecular arrangement, restricted molecular rotation and AIE-oriented emission behavior is the focus of this study. In Chapter 2, 3,4-diphenyl-2,5-bis(4-styryl)thiophene(TP2S)with AEE property showed 2,5-diphenylethene arms emission and tetraphenylthiophene (TP) center emission. β-CD were used as host molecule to encapsulate TP2S and showed an enhanced center emission and a decreased arm emission. Due to the rotational restriction, the TP2S/CD(x/y) (x/y: molar ratio between TP2S and β-CD)complex with emission intensity higher than the pure TP2S. In order to hinder TP2S slip out from β-CD, polymeric PS was used as template to grip the encapsulated TP2Ss through the π-π interactions of the aromatic phenyl rings in TP2S and in PS.When bind to PS, TP2S/CD/PS blends with higher emission intensity than the TP2S/CD complex.
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Chowdhury, Aniket. "Vinylanthracene and Triphenylamine Based Luminescent Molecular Systems : From Aggregation-Induced Emission to Explosive Detection." Thesis, 2016. http://etd.iisc.ernet.in/handle/2005/2968.
Full textAbstract:
In the last few years, considerable efforts have been given to develop sensitive and effective sensors for explosive materials and to generate systems which exhibit high luminescence in both solution and solid-state. The increasing number of terrorist activities around the world have prompted scientists to design effective ways to detect and disarm even the trace amount of explosives. The nitroaromatics (NACs) are the common constituents of most of the explosives due to high explosive velocity and ease of availability. The NACs were extensively used as the main constituents in landmines until World War II. Apart from their explosive behavior, the NACs are well-known environmental pollutants. The industrial waste and the leakages from unexploded landmines are the major contributors towards the soil and ground water contamination.
Presently for effective detection of trace amount of explosives, skilled canines and metal based detectors are commonly used. The canines are trained for a specific type of explosives which limit their ability to detect different types of substrates.
The chemical sensors that work on the principle of colorimetric and/or fluorimetric detection techniques have emerged as suitable alternative due to cheap production cost, portability and sensitivity. Different types of materials including conjugated polymers, metal-organic frameworks (MOFs), and quantum-dots have been reported as efficient chemosensors for NACs. However, poor solubility in the common organic solvents, low solid-state fluorescence, very high molecular weight and lack of signal amplification have restricted the application of these material for in-field testing. Renewed interests have been invested in small molecule based systems; and metal-organic discrete molecular architectures due to precise control over their photophysical properties and the supramolecular interaction among neighboring molecules that facilitates energy migration among the molecular backbone.
On the other hand, recently post-synthetic modification of different molecular systems including MOFs and polymers has emerged as a potential technique to incorporate desired functional groups into the system and to tune their properties with the retention of basic structures. Reports on the post-synthetic modification of discrete metal-organic architectures are rare due to the delicate nature of the metal-organic bonds that ruptures on mild environmental changes.
Therefore, post-synthetic functionalization of discrete molecular systems using mild reaction conditions will open up a myriad of possibilities to generate new systems with desired characteristics.
Chapter 1 of the thesis will briefly discuss the history of different explosive materials including different detection methodologies that are widely used. It will also include a brief discussion on different small molecular systems with high solid-state luminescence.
In Chapter 2, design and synthesis of triphenylamine-based two Platinum(Pt)(II) molecules functionalized with carboxylic acid and ester groups including their organic analogues have been discussed. The triphenylamine core was chosen due its unique non-planarity and luminescence. On the other hand, Pt(II) center was incorporated to increase intermolecular spacing in solid-state that can induce high luminescence.
Scheme 1. Schematic representation of fluorescence quenching using small molecules.
All the four molecules were found to be highly sensitive towards NACs including picric acid and dinitrophenol. Although the molecules exhibited similar sensitivity in solution, the carboxylic acid analogues demonstrated superior sensitivity in solid-state. Careful observation of the crystal structures of the systems revealed the acid analogues were oriented in a 2-D grid-like pattern that facilitated energy migration among neighboring molecules (Scheme 1.).
Chapter 3 describes design, synthesis, and NACs sensing behavior of anthracene-based four purely organic small molecules.
The molecules exhibited high selectivity towards picric acid only. All the molecules were found to be highly emissive in both solution and solid-state due to the vinylanthracene backbone (Scheme 2.).
Scheme 2. Schematic representation of fluorescence quenching and solid-state sensing behavior.
Chapter 4 discusses the strategy to develop mechano-fluorochromic and AIE active triphenylamine-based Pt(II) complex and its organic analogue. The twisted triphenylamine backbone restricted molecular close packing in solid-state; and weak C-H-- interactions were utilized to hinder the motion of the phenyl rings. As a result, the molecules were highly emissive in solid-state. Grinding disrupted the intermolecular interactions and thus mechano-fluorochromic behavior was observed. Due to twisted backbone, the molecules were also found to be AIE active. Both the systems containing terminal aldehyde groups were finally utilized for selective detection of biomolecule cysteine (Scheme 3.).
Scheme 3. Mechano-fluorochromic and AIE behavior of the triphenylamine based Pt(II) complex.
In Chapter 5 vinylanthracene-based linear donor was used in combination with carbazole-based 90° and triphenylamine-based 120° Pt(II) acceptors to generate (4+4) and (6+6) molecular squares and hexagons, respectively. The vinylanthracene backbone imparts high solution and solid-state luminescence to the system as well as made them AIE active. The molecules were further investigated for the solution and solid-state sensing for NACs and found to be effective for trinitrotoluene (TNT) and dinitrotoluene (DNT) (Scheme 4.).
Scheme 4. Schematic representation of AIE active molecular square and its NACs sensing.
Chapter 6 describes the formation of Pd3 self-assembled molecular trinuclear barrels containing triphenylamine imidazole donors and Pd(II) acceptors. Using Knoevenagel condensation the aldehyde group present in the barrel was post-synthetically functionalized with Meldrum’s acid. From spectroscopic characterization, it was proved that the structural integrity remained intact after the post-modification treatment (Scheme 6.). Surprisingly, pre-synthetic modification of the donor alone with Meldrum’s acid followed by self-assembly treatment with the Pd(II) ion did not yield trigonal barrel 6.8.
Scheme 6. Post-synthetic functionalization of trinuclear barrels using Knoevenagel condensation.(For colour pictures pl see the abstract pdf file)
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Chou, Tsu-Yu, and 周子喻. "Photophysical Properties of Thermally Activated Delay Fluorescence and Aggregation Induced Emission Organic Light Emitted Devices." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/48rchh.
Full text
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Sudhakar, Pagidi. "Rational Design Facile Synthesis of Boryl Anilines : Intriguing Aggregation Induced Emission and External Stimuli Responsive Properties." Thesis, 2015. http://etd.iisc.ernet.in/2005/3884.
Full textAbstract:
The main thrust of this thesis is the development of facile synthetic routes for simple boryl anilines and study their structure-property correlations in both solid and solution states and to utilize this information to design functional materials with desired properties such as aggregation induced emission, mechanofluorochromism, and thiol sensors. This thesis contains eight chapters and the contents of each chapter are described below.
Chapter 1
The first chapter is an introduction to the theme of the thesis and presents a general review on the present work with emphasis on photophysics of triarylboron based donor-acceptor systems and their applications in various fields. In addition, advances in boron chemistry in the new frontier areas such as aggregation induced emission and mechanochromism are discussed in brief.
Chapter 2
The second chapter deals with the general experimental techniques and synthetic procedures utilized in this work.
Chapter 3
This chapter describes the rational design and synthesis of triarylborane bearing Unsubstituted amines, namely borylanilines (3.1-3.5). Compounds 3.1-3.4have similar donor and acceptor centres but differ their molecular conformations and also differ in the relative positions of amine moiety (para and meta). Compounds 3.1-3.4 contain one amine group while 3.5 contains two amine moieties. These compounds exhibit fascinating electrostatic intermolecular interactions, N −H- - -π in the crystal structure of 3.1, 3.2 and 3.4 and N −H--N interactions in crystal structure of 3.5. The solution state optical properties of 3.1-3.5 are typical of donor-acceptor (D-A) systems. Interestingly, compounds 3.3 and 3.5 showed unprecedented mechanochromic luminescent properties. Upon grinding, compound 3.3 showed color changes from blue to cyan blue and 3.5 showed intriguing color changes from blue to green and these color changes were found to be reversible. Single crystal X-ray diffraction analysis of 3.5BP (blue emission color crystal) and 3.5GP (green emission color crystal) clearly show that the color changes are due to the difference in their solid state packing.
Chapter 4
In chapter 4, the design and facile synthesis of boron based donor-acceptor (D-A) systems such as borylanilines 4.4-4.9 (D= -NH2 for 4.4-4.6 and -NMe2 for compounds 4.7-4.9) are reported. Compounds 4.4, 4.5 and 4.6 contain one, two or three -NH2 moiety(ies), respectively. Compounds 4.7, 4.8 and 4.9 contain one, two or three –NMe2 moiety(ies), respectively. A systematic investigation has been carried out to rationalize the effect of donor-acceptor ratio on the ICT process in borylanilines 4.4-4.9. The aryl spacer between donor amine and acceptor boron is kept the same in all the compounds to avoid the electronic effect of spacer on the ICT characteristics of these compounds. In the case of compounds 4.4-4.6, the increase in the number of donor -NH2 moieties does not affect their absorption profile, while in the case of compounds 4.7-4.9, the absorption spectra are shifted bathochromically with an increase in the number of donor-NMe2 moieties. Photoluminescence (PL) of 4.4-4.6 is significantly blue shifted with an increase in number of –NH2 moieties, while the PL of 4.7-4.9 was slightly blue shifted. The absorption and PL features of 4.4-4.6 are sensitive to the polarity of the solvent medium. In contrast, absorption profiles of 4.7-4.9 are not sensitive to the polarity of the solvent medium. The PL of these compounds is affected by the polarity of the solvent medium.
Chapter 5
This chapter deals with triarylboron based fluorescent probes (5.1-5.4) for the selective detection of thiophenols over aliphatic thiols. The probes were constructed by conjugating luminescent borylanilinies with luminescent quencher 2,4-dinitrobenzene sulfonyl (DNBS) moiety. In compound 5.1 and 5.2 the DNBS moiety is positioned at the para position with respect to the triarylborane moiety, while in 5.3 and 5.4 the DNBS moiety(ies) is(are) at the meta position(s). Probes 5.1-5.4 showed selective turn-on fluorescence response towards thiophenol. The fluorescence “off-on” switching mechanism of 5.1-5.4 against thiophenols was fully elucidated by theoretical calculations. Probes 5.1-5.4 are also capable of detecting thiophenols in the intra cellular environments.
Chapter 6
Design, facile synthesis and aggregation induced emission properties of a new series of novel triarylboron tethered N-aryl-1,8-naphthalimides (TAB-NPIs) 6.1-6.7 are described in this chapter. Systematic structural perturbation has been used for fine-tuning the optical and morphological properties of TAB- NPIs in both solid as well as in aggregated state. Compounds 6.1-6.7 are weekly luminescent in solutions. In contrast, all compounds (except compound 6.4) are strongly luminescent in the solid state and aggregated state in THF-H2O mixtures. The presence of sterically hindered boryl unit in 6.1-6.7 has endowed these molecules with unique AIE characteristics by preventing co-facial arrangements of NPI moieties. The propeller shape arrangement of TAB moiety in 6.1, 6.2, 6.5, 6.6 and 6.7 effectively prevents the aggregation induced emission quenching (AIEQ) and induce strong emission in the condensed state. In the solid state, compounds 6.1, 6.4, 6.5, and 6.6 generate an interesting supramolecular structure via intermolecular C-H--- and C-H---O interactions. No face to face intermolecular π---π interactions were found in the crystal structures of 6.1, 6.4, 6.5, and 6.6. This precludes the excimer formation which can be detrimental to the radiative process in these molecules. The scanning electron microscopy (SEM) images of as prepared samples of 6.1-6.7 clearly indicate that the morphology of these compounds strongly depends on the molecular conformations and number of naphthalimide moieties in the TAB-NPI conjugates.
Chapter 7
This chapter deals with design, synthesis and optical properties of novel dimesitylboryl appended perylenediimides. A simple synthetic strategy has been developed for the construction of novel TAB-PDIs conjugates. These conjugates can be conveniently synthesised by condensation of boryl anilines with perylene tetracarboxylic acid anhydride. The incorporation of TAB moiety enhanced the solubility of perylen bisimides in common organic solvents. The PL quantum yield of both 7.1 and 7.2 strongly depends on the excitation wavelength. Lower Pl efficiency observed for 7.1 and 7.2 upon excitation in the boryl dominated absorption region may be due to the photon induced electron transfer form mesityl units of boryl to perylene bisimide moiety. The morphology as well as emission colours of supramolecular architectures of both 7.1 and 7.2 can be modulated by controlling the concentrations of DCM solutions of these compounds. Both the compounds showed selective fluorogenic response for F-1 and CN-1
anions. The simple synthetic strategy reported in this chapter can be conveniently exploited for the construction of TAB conjugates of semiconducting organic anhydrides.
Chapter 8
Novel planar chiral Lewis acids 8.3(SP, SS), 1-phosphino-2-borylferrocenes 8.4(SP) and 2-phosphino-1-borylferrocenes 8.4(RP) have been synthesized from a readily accessible ferrocene sulphinate precursor. Adopting a simple synthetic approach and a single precursor, enantiomerically pure SP and RP isomers have been prepared. It would be worthwhile to investigate the catalytic properties of compounds 8.3(SS), 8.4(SP) and 8.4(RP). It would also be interesting to replace the mesityl groups on boron with other electron deficient groups like pentafluorophenyl and 1,3,5-trifluoromethylphenyl to fine tune the Lewis acidity of boron center and to set-up a general route to enantiomerically pure Planar Chiral Frustrated Lewis Pairs (PCFLP’s).
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Zhan, Fu-Kai, and 詹富凱. "The Effects of Alkyl Chain Length and Aggregation-Induced Emission Chromophore on Organic Self-Assembled Nanomaterials." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/36986890510788709767.
Full textAbstract:
碩士國立交通大學
材料科學與工程學系所
104
Recently, research of molecules behavior gradually matured, further controlling strength or weakness of molecular interaction, which is the origin of self assembly materials. The first part in my study, we discussed the effect of changing alkyl chain length on naphthalene diimide (NDI) to dipeptide self assembly. We chose methylamine、ethylamine、n-propylamine、n-butylamine and n-octylamine to be the aliphatic chain length on naphthalene diimide, connecting tyrosine and phenylalanine as peptide sequence to improve the value of application. In addition, we discovered different physical properties by chaning alkyl chain length. Carbon chains length affected critical gelation pH. As the length was decreased, the critical pH value changed from higher to lower. Minimum gelation concentration (MGC) increased with the chain decrease of carbon length. Sol-gel transition temperature and storage modulus (G’) on rheology increased as carbon chains increasing. In photo-luminescence (PL), fluorescence intensity decreased with increasing concentration and happened red shift. This demonstrated aggregation-caused quenching (ACQ) properties. In the second part, we synthesized biofunctional peptid sequence conjugated with tetraphenylethene (TPE) to produce aggregation-induced emission (AIE). We selected DGEA and RGD as biological sequence. 1 wt% TPE-GDGEA could’t form hydrogel but formed hydrogel at 3 wt% under acidic environment. 1 wt% TPE-FDGEA formed hydrogel under acdic environment and hydrogel at 3 wt% was formed under neutral environment. 3 wt% TPE-FDGEA has the hightest on sol-gel transition temperature and rheology. The structure of 3 wt% TPE-GDGEA hydrogel present naroribbons while TPE-GDGEA hydrogels under and all concentraitons including TPE-FDGEA were nanofibers. For biological experiments, 3 wt% TPE-FDGEA was better than TPE-GDGEA, because 3 wt%TPE-FDGEA could form hydrogel under netural environment. In order to investigate the difference between RGD and RGE, we also synthesized TPE-FRGD and TPE-FRGE. The both 1 wt% TPE-FRGD and 1 wt% TPE-FRGE formed hydrogel under acidic environment, while TPE-FRGD on sol-gel transition temperature and rheology was higher than TPE-FRGE and their structure present nanofibers.In addition, water fraction experiment indicated the both TPE-FRGD and TPE-FRGE displayed the AIE properties. On biological experiments, the both could enter into cells and performed fluorescence. In the future, the two TPE derivatives develop a prospective and novel materals with applying in the field of health and medicine.
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Ping-FengHsu and 許秉豐. "A novel pyrene-Schiff base fluorescent ‘turn on’ sensor toward Zn2+ and Al3+ with aggregation-induced emission enhancement." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/uebdm5.
Full textAbstract:
碩士國立成功大學
化學工程學系
104
A novel fluorescent sensor PySb comprising of pyrene moiety as the fluorophore, benzene ring as the spacer, and 2-(hydroxymethyl)propane-1,3-diol as the ionophore was synthesized. PySb itself exhibited weak fluorescence due to photoinduced electron transfer (PET). It can serve as a highly selective and sensitive fluorescent ‘turn on’ sensor toward (a) Zn2+ in ethanol solution (λem = 470 nm) and (b) Al3+ in DMSO solution (λem = 458 nm). The complexes of PySb-Zn2+ and PySb-Al3+ were further supported by 1H NMR spectra. The 1:2 stoichiometry between PySb and Zn2+ was obtained from Job plot. Excellent detection limit toward Zn2+ (2.39×10-8 M) was derived from titration experiment. Similarly, the binding constant toward Zn2+ was estimated as 2×109 M-1 based on titration experiment. PySb-Zn2+ complex in DMF solution showed aggregation-induced emission enhancement with increasing content of ethanol (0-99%). It could be utilized as a fluorescent sensor in a wide range of pH (3-11). Green emission of PySb (λem = 515 nm) was observed when pH was higher than 12 due to intramolecular charge transfer (ICT).
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Fu, Jin-Yuan, and 富靖元. "Fluorescent Light-up Probe with Aggregation Induced Emission for β-galactosidase Sensing and its application in living cells." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/me98a5.
Full textAbstract:
碩士國立交通大學
應用化學系碩博士班
107
TPE-gal for detecting β-galactosidase. β-galactosidase is a crucial biomarkerused to identify malignant tumorsand also associated with cell senescence.Compared to a normal ovarian cell, β-galactosidase in primary ovarian cancers cell is much higher. Therefore, the probe TPE-galconsists of tetraphenylethylene as a chromophore and two galactose groups as anenzyme-responsive moiety for β-galactosidase. Furthermore, two galactose moieties can greatly increase the solubility of the probe in water and prevent aggregation and emission. When β-galactosidase is detected, two galactosesin the probe was cut off to release a lower water-soluble chromophore, tetraphenylethylene, and causeaggregation induced emission. The fluorescent probe TPE-gal has shown high selectivity for detecting β-galactosidase and excellent biocompatibility to investigate endogenous β-galactosidase in the ovarian cancer cell, SKOV-3.
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Chan, Han-Chieh, and 詹涵絜. "Syntheses of Tetraphenylethene Bridged Biscalix[4]arene Derivatives and Studies of Their Organogel Properties and Aggregation Induced Emission." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/723kf5.
Full textAbstract:
碩士國立交通大學
應用化學系碩博士班
108
In this thesis, we designed and synthesized tetraphenylethene bridged biscalix[4]arene derivatives (E)-30, (Z)-30, (E)-31 and (Z)-31 by click reaction. Control compounds (E)-34 and (Z)-34 were also synthesized for comparison. We have previously reported a serendipitous discovery that triazole bridged biscalix[4]arenes form organogels in certain conditions. These compounds were tested and we found that only compound (E)-30 was able to form gel with fluorescent in certain solvents. The gelation properties and self-assembly morphologies of compound (E)-30 was further examined by SEM, Variable-temperature 1H-NMR, IR spectroscopy and SEM to gain insight into the possible packing model. In addition, because these derivatives incorporated with tetraphenylethene scaffold, we also investigated their aggregation induced emission behavior. We revealed that different water fraction was required to initiate the AIE effect of all compounds. At the same time, we observed that all compounds have a slight blue shift when the fraction of water increases. The morphologies of the aggregated compounds were also examined by SEM.
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Lai, Chung-Tin, and 賴俊廷. "Effect of molecular structure on the aggregation-induced emission properties of organic and polymeric materials containing tetraphenylthiophene or triphenylpyridine moiety." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/69101888517969686629.
Full textAbstract:
博士國立中山大學
材料與光電科學學系研究所
100
About half a century ago, Főrster and Kasper discovered that traditional organic chromophore such as pyrene was weakened with an increase in its solution concentration. It was soon recognized that this was a general phenomenon for many aromatic compounds. This concentration-quenching effect was found to be caused by the formation of sandwich-shaped (disc-like) excimers and exciplexes aided by the collisional interactions between the aromatic molecules in the excited and ground states. In 2001, Tang’group discovered such a system, in which luminogen aggregation played a constructive, instead of a destructive, role in the light-emitting process: a series of silole molecules were found to be non-luminescent in the solution state but emissive in the aggregated state. They coined the term ‘‘aggregation-induced emission’’ (AIE) or “AIE enhancement” (AIEE) for this novel phenomenon which originated from the restricted intramolecular rotation (RIR) inherent from the chemical structures of the luminescent materials. To verify the effect of molecular structure on the AIE properties of organic and polymeric materials, four approaches were attempted in this research. (I) Aggregation-Induced Emission in Tetraphenylthiophene-Derived Organic Molecules and Vinyl Polymer Organic molecules of tetraphenylthiophene (TP) and the derived model compound of TP-Qu and vinyl polymer of PS-Qu with the pendant group of TP-Qu were prepared and characterized to identify their photoluminescent responses toward the effect of AIE. During aggregate formation, the corresponding TP solutions greatly gained the emission intensity. In contrast, TP-Qu and PS-Qu in isolated or aggregated states emitted strongly with nearly the same emission intensity. RIR is the key factor deciding the AIE effect in different states. With four small phenyl rotors around the central thiophene stator, the RIR of the TP molecules in dilute solution is low but increases upon aggregate formations. In contrast, the bulky C-2 quinoline rotor of the TP-Qu molecule enhances the RIR in isolated state. With the inherent TP-Qu pendant groups, the emissive behavior of vinyl polymer PS-Qu is similar to the TP-Qu molecule. (II) Aggregation-Induced Emission Enhancement of Diblock Copolymer Containing Tetraphenylthiophene-Quinoline Pendant Fluorphores by Selective Solvent Pairs In this study, diblock copolymer of PSQu-PBS containing 25 mol% of fluorescent PSQu segments was synthesized and its aggregation-induced emission enhancement (AIEE) behavior was characterized and compared to PSQu homopolymer with 100 mol% of fluorescent units. With fewer (25 %) fluorescent units, solutions of diblock PSQu-PBS copolymer actually have higher (or comparable) emission intensities than the homopolymer PSQu solutions. Solutions of PSQu-PBS in THF/H2O of varied compositions emit essentially with the same intensity but in contrast, emissions of PSQu-PBS in THF/hexane increase with the increasing hexane content. Copolymer micelles formed in THF/hexane mixtures are supposed to have higher extent of aggregation, leading to more pronounced AIEE effect than micelles formed in THF/H2O. (III) Tetraphenylthiophene-Functionalized Poly(N-isopropylacrylamide): Probing LCST with Aggregation-Induced Emission A hydrophobic TP center with novel AIE property was chemically linked to two poly(N-isopropylacrylamide) (PNIPAM) chains to obtain thermoresponsive polymers to study the relationships between the lower critical solution transitions (LCSTs) and the AIE-operative fluorenscence emission. Three ethynyl-terminated PNIPAMs with different molecular weights were synthesized via controlled atom transfer radical polymerization (ATRP) using ethynyl-functionalized initiator. The PNIPAMs were then coupled with diazide-funtionalized TP (TPN3) via click reaction to obtain the desired TP-embedded polymers of Px (x = 1, 2, and 3). All three polymers show AIE-property from their solution fluorescence behavior in THF/hexane mixtures. In the aqueous solution, the TP-center served as a fluorogenic probe that reveals the LCSTs of polymers and its relation to the degree of TP labeling in terms of polymer concentration. The thermoresponsiveness of Px was demonstrated by the complete emission quench when heated at temperatures above LCST. Dissociation of the TP aggregates above LCST is responsible for the emission quench. (IV) Influence of Molecular Weight on the Aggregation-Induced Emission of Vinyl Polymers Containing the Fluorescent 2,4,6-Triphenylpyridine Pendant Groups Molecular weight effect on the AIEE property of vinyl polymers containing fluorescent 2,4,6-triphenylpyridine (TPP) pendant groups was evaluated in the fourth topic. The high and low Mw vinyl polymers of PDMPS–L and –H were prepared through Click chemistry between azide–TPP derivative and acetylene–functionalized polystyrenes. Solutions of the low Mw PDMPS–L exhibited the normal AIEE effect with continuous emission gains with increasing extent of aggregation upon nonsolvent inclusion. On the contrast, the high Mw PDMPS–H solutions emitted with constant intensity on all solutions with different extent of aggregation. Despite the varied solution behavior, the solid PDMPS-L and –H films are all strong deep-blue emitter with high quantum yields of 84 and 82.5%, respectively. The emission behavior was explained by the conformational difference between the PDMPS–L and –H chains, which were approached by computer simulation in this topic.
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Li, Shu-ting, and 李書廷. "Aggregation induced emission enhancement in relation to the secondary structures of poly(γ-benzyl-L-glutamate) containing fluorescent tetraphenylthiophene moiety." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/52579614275986135825.
Full textAbstract:
碩士國立中山大學
材料與光電科學學系研究所
100
In this study, tetraphenylthiophenen (TP) with aggregation-induced emission enhancement (AIEE) property is served as terminal and central fluorophores of poly(γ-benzyl-L-glutamate) (PBLG)-based polymers of TP1PBLG and TP2PBLG, respectively, to probe for the relationship between the secondary structure (α-helix) of polypeptides and the ALEE-operative fluorescence (FL). Intermolecular aggregation of the central TP unit in the di-substituted TP2PBLG is sterically blocked by the large α-helical PBLG chains, which lead to the reduced AIEE-oriented FL. On the contrast, the terminal TP units in TP1PBLG can easily approach each other to form aggregates with strong FL. Factor (e.g. solvent annealing) controlling the fraction of α-helix chain also varies the corresponding emission intensity. Conformational difference between TP1PBLG and TP2PBLG evaluated from the infrared and the X-ray (wide- and small-angle) diffraction spectra is also used to verify its influence on the AIEE-operative FL behavior.
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Chang, Kai-Wen, and 張凱文. "Investigation of organic light-emitting devices using resonant cavity structure and lasing properties of organic emitters with aggregation induced emission characteristics." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/ynn8d4.
Full textAbstract:
碩士國立中山大學
光電工程學系研究所
102
The first part of this thesis is concentrated on the color purity performance improvement of blue phosphorescent OLEDs. We integrated a high efficiency blue OLEDs with conducting DBR anodes, then optimized this device by modulating the thickness of organic films. With this configuration, we successfully improved the color purity of the blue-emitting device. The CIE 1931 color coordinate of the blue-emitting device with cavity structure was located at (x,y)= (0.14,0.14), and it of the device with no cavity structure was located at (x,y)=(0.14,0.35). In the second part of this thesis, we investigated two materials with aggregation induced emission (AIE) properties named as TPATPE and 2TPATPE. Due to their high steric hindrance, they can be well utilized in high efficiency OLEDs. First, we set the amplified spontaneous emission (ASE) experiments to measure their ASE thresholds, ASE spectrum, gain coefficients and loss coefficients. The results revealed that both TPATPE and 2TPATPE have good optical amplification properties with ASE thresholds about 2.7kW/cm2 and 4.9kW/cm2 and gain coefficients are 19cm -1 and 23cm-1, respectively. With a suitable resonant condition realized by 1-D DFB structure and the high gain materials, spectral narrowing and optical amplification properties were observed. Finally, two double-layered florescent OLEDs with high efficiencies were demonstrated. The EQE of TPATPE and 2TPATPE devices were 4.3% and 4.6%, respectively. This results indicated that both of these two materials are well suitable for display or lighting applications.
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Pacheco, João Adriano. "Synthesis and biological evaluation of analogs of the green fluorescent protein fluorophore." Master's thesis, 2021. http://hdl.handle.net/10773/30613.
Full textAbstract:
This dissertation approaches the synthesis of imidazolones, particularly 3,5-
dihydro-4H-imidazol-4-ones, and their photophysical properties as AIEgens and
cellular component probes.
Imidazolones are a class of heterocyclic natural compounds comprised of a five
membered ring containing two nitrogen atoms. Imidazolones are
biosynthesized by means of an autocatalytic cyclization and oxidation of a SerTyr-Gly chromogenic tripeptide. This peptide is of interest due to its fluorescent
properties while enclosed in the β barrel of the green fluorescent protein (GFP).
This protein and its similars have countless applications in almost all fields of
life sciences, making this class of compounds of major interest for the
fluorescent dye fields.
In the first chapter, an introduction will be presented, where fluorescence basic
concepts and their practical applications on cellular labelling will be presented.
In the same chapter, GFP history, structure, and applications will be explored.
Some of the synthetic methods to obtain GFP fluorophore and its analogs are
described, highlighting some different synthetic strategies. Finally, commercial
fluorescent dyes’ targeting groups for different cell components will be
analyzed.
In the second chapter, the synthetic methods are described and discussed,
followed by the complete characterization of one compound as an example for
the analysis of the different spectroscopic techniques’ results, like 1H and 13C
Nuclear Magnetic Resonance (NMR), Heteronuclear Single Quantum
Coherence (HSQC) and Heteronuclear Multiple Bond Correlation (HMBC),
high-resolution mass spectrometry (HRMS), UV-Vis spectra, and THF-Water
aggregation tests. In the same chapter, biological assays are described,
namely resazurin cytotoxic assay and SH-SY5Y cell staining assay. From the
obtained results, it is possible to conclude that the probes are not cytotoxic and
can be used as vital dyes, but only one shows promising cell staining results.
In the third and final chapter, the detailed description of the experimental
procedures used throughout this work is addressed.
Finally, conclusions are drawn, and some future perspectives are presented.Esta dissertação aborda a síntese de imidazolonas, particularmente 3,5- dihidro-4H-imidazol-4-onas, e as suas propriedades foto físicas como AIEgens e marcadores de componentes celulares. Imidazolonas são uma classe de compostos heterocíclicos constituídos por um anel de cinco lados contendo dois átomos de azoto. Imidazolonas são biossintetizadas via a ciclização seguida de uma oxidação autocatalíticas do tripéptido cromogénico Ser-Tyr-Gly. Este péptido é de grande interesse devido às suas propriedades fotofísicas aquando incluído no barril β da proteína fluorescente verde (GFP). Esta proteína e similares têm inúmeras aplicações em quase todas as áreas de ciências da vida, fazendo com que esta classe de compostos seja de grande interesse no campo dos corantes fluorescentes. No primeiro capítulo, uma introdução será apresentada, onde conceitos básicos de fluorescência e as suas aplicações práticas em marcação celular serão abordados. No mesmo capítulo, história, estrutura, e aplicações da GFP serão exploradas. Alguns dos métodos sintéticos usados para obter o fluoróforo da GFP e seus análogos são descritos, destacando algumas estratégias sintéticas diferentes. Finalmente, os targeting groups de diferentes corantes fluorescentes comerciais para diferentes componentes celulares serão analisados. No segundo capítulo, os métodos sintéticos usados neste trabalho são descritos e discutidos, seguidos da caracterização completa de um composto usada como exemplo para o raciocínio usado na análise dos resultados das diferentes técnicas espectroscópicas, como Ressonância Magnética Nuclear (NMR) 1H e 13C, Heteronuclear Single Quantum Coherence (HSQC), Heteronuclear Multiple Bond Correlation (HMBC), espectrometria de massa de alta resolução (HRMS), espectros UV-Vis, e testes de agregação em THFÁgua. No mesmo capítulo, ensaios biológicos são descritos, nomeadamente o ensaio de citotoxicidade com resazurina e o ensaio de marcação celular em células SH-SY5Y. Dos resultados obtidos é possível concluir que os compostos não são citotóxicos e podem ser usados como corantes vitais, no entanto apenas um composto mostrou resultados de marcação celular promissores. No terceiro e final capítulo, uma descrição detalhada dos procedimentos experimentais usados ao longo deste trabalho é apresentada. Por último, são também tiradas conclusões e algumas perspetivas para trabalhos futuros.
Mestrado em Bioquímica
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Fontes, Luís Filipe Baptista. "Synthesis and photophysical properties of triphenylpyridine derivatives." Master's thesis, 2019. http://hdl.handle.net/10773/30093.
Full textAbstract:
In this study, triphenylpyridine derivatives were synthetized and fully characterized,
including their photophysical properties. The triphenylpyridine core presented
fluorescence in solution with quantum yields that surpass anthracene’s, with compound
[4-(2-(2-methoxyphenyl)-6-phenylpyridin-4-yl)-N,N-dimethylaniline] being the
brightest. This study allowed to identify the importance of 2-(pyridin-2-yl)phenol
moiety for achieving fluorescence in solid state and not in solution. Complexation of
boron was attempted for 2-(pyridin-2-yl)phenol derivatives with boron trifluoride,
however the complex was not stable in solution. Five derivatives were analysed by
single crystal x-ray diffraction and their structural features were indicative of the
possibility of solid-state emission with very weak intermolecular and intramolecular
interactions. All derivatives presented solid-state fluorescence with three compounds
showing potential for further solid-state luminescence studies.Neste estudo foram sintetizados e caracterizados derivados de trifenilpiridinas. Os derivados de trifenilpiridina apresentaram fluorescência, com alguns derivados a apresentarem rendimentos quânticos de fluorescência acima do composto de referência (antraceno). O composto [4-(2-(2-metoxifenil)-6-fenilpiridin-4-il)-N,N-dimetilanilina] apresenta ser o derivado com valores superiores de rendimento quântico de fluorescência. Os estudos realizados permitiram identificar a importância do grupo 2- (piridin-2-il)fenol para obter fluorescência em estado sólido e não em solução. Foi tentada a complexação de boro com os derivados de 2-(piridin-2-il)fenol com eterato de trifluoreto de boro no entanto os complexos obtidos não mostraram ser estáveis em solução. Cinco dos derivados foram analisados por cristalografia de raio-x: -os resultados permitiram avaliar as interações intramoleculares e intermoleculares em estado sólido. Todos os derivados apresentaram fluorescência em estado sólido demonstrando o potencial de fluoróforos baseados em trifenilpiridina para futuros estudos de luminescência em estado sólido.
Mestrado em Química
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Arumugaperumal, Reguram, and 艾瑞嵐. "Design and Synthesis of Ratiometric Sensors and Multi-Stimuli Responsive Fluorescence Molecular Switches with Novel BODIPY/Tetraphenylethene (TPE) Functionalized [2]Rotaxane and a Controllable Aggregation Induced Emission Behavior." Thesis, 2022. http://ndltd.ncl.edu.tw/handle/39660963103699833500.
Full textAbstract:
博士國立交通大學
材料科學與工程學系所
105
The pivotal objective of this dissertation is to design and construct novel fluorescent switchable mechanically interlocked molecular architectures with symmetric stopper and to study their molecular shuttling process under acid-base stimuli control along with their controllable high contrast fluorescence and impressively selective detection of anionic guest species. In the introduction of this doctoral thesis we have described brief early synthetic attempts to create mechanically interlocked molecules (MIMs) such as rotaxanes and catenanes as well as several chemosensing mechanism and aggregation induced emission (AIE). Moreover novel templating methodologies to build MIMs and some latest examples of fluorescence MIMs based molecular shuttles under different control stimuli were also introduced. Indeed, acid-based stimuli can drive the molecular shuttling between the two stations accompanied by changing the AIE behavior of AIE-active mechanically interlocked molecule investigated. Fairly, underplayed chemo sensing mechanisms in these systems were presented. Meanwhile, we have developed facile ratiometric sequential detection of copper and pyrophosphate based on rhodamine appended derivatives in this doctoral thesis as well. In chapter two, a novel multifunctional mechanically interlocked switchable [2]rotaxane R4 containing two molecular stations and rotaxane arms terminated with boron-dipyrromethene (BODIPY) fluorophores and its derivatives were synthesized for the first time by CuAAC click reaction. The shuttling motion of macrocycle between the dibenzylammonium and triazolium recognition sites and the distance dependent photoinduced electron transfer process of R4 is demonstrated by utilizing external chemical stimuli (acid/base). Interestingly, the reversible self-assembly process of R4 was recognized by the acid–base molecular switch strategy. Notably, two symmetrical triazolium groups acted as molecular stations, H2PO4– receptors, and H-bonded donors. Both [2]rotaxane R4 and thread R2 demonstrated excellent optical responses and high selectivity toward H2PO4– ion. The specific motion and guest–host interactions of mechanically interlocked machines (MIMs) were also further explored by quantum mechanical calculations. The thread R2 also demonstrated to enable the detection of H2PO4– in RAW 264.7 cells successfully. In chapter three, a novel near IR fluorescent switchable [2]rotaxane NIR4 composed of two different molecular stations and rotaxane arms terminated with near IR boron-dipyrromethene (BODIPY) fluorophores and its derivatives were synthesized for the first time by CuAAC click chemistry. The molecular shuttling motion could be addressed by the fluorescence signal transduction via distance dependent photo-induced electron transfer process of [2]rotaxane NIR4 triggered by external chemical stimuli (acid/base). The construction and efficient synthesis of [2]rotaxane NIR4 with high level of structural complexity designed always more challenging task of selective anion sensing. Conspicuously, the key to design involved encoding the flexible arms of [2]rotaxane NIR4 triazolium moiety acted as molecular stations and H-bonded donors, which exhibits impressive selectivity and sensitivity toward complementary anionic gust species. The specific mechanical molecular motion of [2]rotaxane NIR4, host-guest interactions of NIR2 and mechanically interlocked molecules (MIMs) were also further explored by quantum mechanical calculations. Importantly, the host of NIR2 and [2]rotaxane NIR4 could be applied for the vivo imaging and clarify the distribution of H2PO4- at subcellular levels. In chapter four, a novel AIE-active switchable [2]rotaxane TR2 incorporating two different molecular stations and rotaxane arms terminated with AIE-active TPE fluorophores and its derivatives were synthesized for the first time by click chemistry. The shuttling behavior of macrocycle component between the two molecular stations can be driven by external acid-base stimuli in solution, accompanied by NMR spectral changes. Investigation of their AIE fluorescence behavior changes showed that these analogous rotaxane are controlled by the molecular motion of the macrocycle component in the presence of external acid-base stimuli. The anion-templated construction of [2]rotaxane TR2 with high level of structural complexity designed always more challenging task. Evidently, the key to design involved encoding the flexible arms of both triazolium motif, is described which exhibit impressive selectivity and sensitivity toward complementary anionic gust species. The specific mechanical molecular motion and host-guest interactions of mechanically interlocked machines (MIMs) were also further explored by quantum mechanical calculations. Importantly, the AIE- active behaviors of [2]rotaxanes TR1, TR2 and TR3 were further investigated to study their potential bio-imaging application and specifically [2]rotaxane TR2 could be applied in vivo imaging with H2PO4- at subcellular levels. In chapter five, two rhodamine hydrazine derivatives Rh1 and Rh2 with catechol and ether functionalities have been synthesized and utilized towards sequential colorimetric detections of Cu(II) and pyrophosphate (PPi) ions in CH3CN–H2O (v/v = 9 : 1, 5 mM Tris–HCl, pH 7.4) semi-aqueous medium. Notably, Rh1 and Rh2 are the first example of colorimetric rhodamine-based probes for the sequential detections of Cu2+ ion and PPi anion. Based on the significant colorimetric responses (from colorless to pink) of Rh1 and Rh2 to Cu2+ ions, the detection limits were estimated as low as 1.22 × 10−8 M and 8.0 × 10−7 M, respectively, which signified the utilities of designed probes towards facile detections of Cu2+ ions. Furthermore, upon the successive addition of PPi ion to Rh1–Cu2+ and Rh2–Cu2+complexes, it has been altered and restored to its origin of Rh1 and Rh2 via re-coordination of PPi to Cu2+ ion, which was confirmed by color changes from pink to colorless. Moreover, computational DFT calculations provided more insights into HOMO–LUMO structures of rhodamine derivatives and their copper complexes. Additionally, the solid state strip-based colorimetric detections of Cu2+ ion were supplemented as a real time application. Thus in conclusion, novel fluorescence mechanically interlocked molecules designed to act as molecular switches have proceeded apace. Delightfully, the molecular shuttling to achieve by the addition of acid-base and studied on AIE behavior indicate that the molecular motion of macrocycle component could induce change the aggregation state of the AIE-active mechanically interlocked molecule. The remarkable stimulated responses towards dihydrogen phosphate (H2PO4-) were discussed. Furthermore, sequential detection of copper and pyrophosphate via ratiometric sensor based on rhodamine derivatives were presented in detail.
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Cunha, Carla Sofia Duarte. "COMPLEXOS BINUCLEARES DE CUMARINAS-AU(I): Síntese, Fotofísica e Estudos Computacionais." Master's thesis, 2020. http://hdl.handle.net/10316/92274.
Full textAbstract:
Dissertação de Mestrado em Química apresentada à Faculdade de Ciências e TecnologiaNos últimos anos, o crescente interesse e estudo de complexos organometálicos tem ganho cada vez mais destaque principalmente devido à sua fascinante versatilidade e inúmeras aplicações em que estes compostos podem ser empregues. Estes compostos possuem na sua estrutura átomos doadores de eletrões que permitem a coordenação com diferentes metais e possibilitam assim variadas geometrias. Em particular, os complexos derivados de Au(I) representam uma área emergente de investigação, principalmente devido às suas propriedades luminescentes mas também ao possível estabelecimento de interações do tipo metal-metal Au(I)···Au(I) – aurofilicidade. O estudo realizado na presente dissertação incidiu na síntese e caracterização completa das propriedades espetroscópicas e fotofísicas de três novos complexos binucleares derivados de Au(I) tendo como ligando percursor a 4-metil-7-(prop-2-in-1-iloxi)-1-benzopiran-2-ona e a coordenação de diferentes espaçadores bis(difenilfosfinas) com o objetivo de investigar as suas propriedades luminescentes e a possibilidade de exibirem aumento da emissão de fluorescência por diminuição da contribuição do processo não radiativo de conversão interna, dominante nas cumarinas. Dentro dos processos que possibilitassem o aumento da eficiência de luminescência destes compostos, procurou-se a emissão de fosforescência à temperatura ambiente (do inglês, RTP), a fluorescência retardada por amplificação térmica (do inglês TADF ou “reversed intersystem crossing”, rISC) e a emissão induzida por agregação (do inglês, AIE). Numa perspetiva mais aplicada pretende-se que o desenvolvimento de moléculas estáveis com eficiência de luminescência aumentada possam ser aplicadas em díodos orgânicos emissores de luz (do inglês, OLEDs). As experiências de fluorescência em estado estacionário e dinâmico permitiram obter os dados fotofísicos necessários para a compreensão dos diferentes sistemas em estudo; tal foi efetuado em cinco solventes orgânicos e em misturas binárias de solventes (acetonitrilo:água). Foi igualmente investigado o efeito da introdução de diferentes espaçadores (aumento do comprimento da cadeia alifática 2a:CH2; 2b:CH2–CH2–CH2 e o efeito da rigidez com a inserção de uma ligação tripla C≡C, 2c), que modificam a conformação dominante dos complexos em estudo e por consequência as interações intra- e inter- moleculares estabelecidas. Foram determinados todos os rendimentos quânticos, incluindo o rendimento quântico de fluorescência (F), rendimento quântico de fosforescência (P) e o rendimento quântico de formação de singuleto oxigénio (∆) e tempos de vida dos processos de desativação do estado excitado (tempo de vida de fluorescência, fosforescência e estado tripleto). Tal permitiu a obtenção das constantes de velocidade radiativas (kF) e não radiativas (kNR) que determinam a desativação do estado excitado. A conjugação destas técnicas, juntamente com a de dispersão dinâmica de luz (DLS), permitiu observar a presença de agregados nos complexos binucleares derivados de Au(I), confirmando a presença do fenómeno AIE nos compostos pretendidos. Cálculos teóricos de orbitais moleculares (DFT e TD-DFT) foram utilizados como uma ferramenta na racionalização do comportamento observado. Um dos compostos elucidados (2a) mostrou possuir interação aurofílica. Adicionalmente, foram obtidos os espetros de absorção e de emissão de fluorescência no estado sólido (sob a forma de filme), de modo a verificar as interações no estado sólido e se estas podem ser correlacionadas com as observadas em solução.
In recent years, the growing interest and investigation of organometallic complexes has gained increasing prominence mainly due to its fascinating versatility and numerous applications in which these compounds can be used. These compounds have electron donor atoms in their structure that allow coordination with different metals and thus allow different geometries. In particular, gold(I) complexes represent an emerging area of research, mainly due to their luminescent properties but also to the possible establishment of type interactions metal-metal Au(I) Au(I)- aurophillicity.The study carried out in this dissertation focused on the synthesis and complete characterization of the spectroscopic and photophysical properties of three new binuclear Au(I) complexes having as precursor ligand 4-methyl-7-(prop-2-in-1-yloxy)-1-benzopyran-2-one and with the incorporation of different bis(diphenylphosphine) spacers in order to investigate its luminescent properties and the possibility of exhibiting increased fluorescence emission by decreasing the contribution of the internal non-radioactive conversion process, dominant in coumarins. Within the processes that made it possible to increase the luminescence efficiency of these compounds, the emission of phosphorescence at room temperature (RTP), fluorescence delayed by thermal amplification (TADF or reversed intersystem crossing, rISC) and aggregation-induced emission (AIE). In a more applied perspective, it is intended that the development of stable molecules with increased luminescence efficiency can be applied in organic light-emitting diodes (OLEDs).The fluorescence experiments in steady state and dynamic allowed to obtain the necessary photophysical data for the understanding of the different systems under study; this was done in five organic solvents and in binary solvent mixtures (acetonitrile:water). The effect of introducing different spacers (increasing the length of the aliphatic chain 2a:CH2; 2b:CH2–CH2–CH2 and the effect of stiffness with the insertion of a triple bond C≡C, 2c), which modifies the dominant conformation of the complexes in study and consequently the established intra- and inter- molecular interactions. All quantum yields were determined, including quantum fluorescence yield (F), quantum phosphorescence yield (P), and the quantum yield of oxygen singlet formation (∆) and lifetime of state deactivation processes excited (fluorescence, phosphorescence and triplet state lifetime). This allowed obtaining the radioactive (kF) and non-radioactive (kNR) rate constants that determine the deactivation of the excited state. The combination of these techniques, together with the dynamic light scattering (DLS), allowed to observe the presence of aggregates in the binuclear Au(I) complexes, confirming the presence of the AIE phenomenon in the intended compounds. Theoretical molecular orbital calculations (DFT and TD-DFT) were used as a tool in the rationalization of the observed behavior. One of the elucidated compounds (2a) was shown to have aurophilic interaction. Additionally, the absorption and fluorescence emission spectra were obtained in the solid state (in the form of film), in order to verify the interactions in the solid state and if they can be correlated with those observed in solution.
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