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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

[en] CARBAZOLE-BASED COVALENT ORGANIC FRAMEWORKS: CONCEPTION, SYNTHESIS AND CHARACTERIZATION / [pt] COVALENT ORGANIC FRAMEWORKS BASEADOS EM CARBAZÓIS: CONCEPÇÃO, SÍNTESE E CARACTERIZAÇÃO

LEONARDO SIMÕES DE ABREU CARNEIRO 07 December 2016 (has links)
[pt] Materiais bidimensionais apresentam possibilidades de funcionalização que os tornam versáteis para diversas aplicações, tais como em dispositivos eletrônicos. A presença de poros nesses materiais pode trazer novas funções, como adsorção de gases, liberação controlada de fármacos e catálise. Os covalent organic frameworks (COFs) são uma nova classe de materiais orgânicos porosos cristalinos que têm recebido destaque em química reticular. O objetivo dessa dissertação é apresentar a síntese e caracterização de quatro novos COFs baseados em carbazóis, que constitui uma classe de compostos utilizada na obtenção de polímeros condutores. O bloco de montagem principal utilizado foi o 3,6-diamino-9H-carbazol e as fontes de aldeído foram triformilfloroglucinol, triformilfenol, 1,3,5-tri(4-formilfenil)benzeno e triformilbenzeno para a síntese do RIO2, RIO3, RIO5 e RIO6, respectivamente. RIO2 e RIO3 apresentaram-se sob a forma ceto enamina e imina, respectivamente, além de pouca cristalinidade e baixa área específica. Através de cálculos baseados na Teoria do Funcional da Densidade (DFT), foi verificado que esses COFs apresentam suas folhas deslocadas e rotacionadas devido às interações eletrostáticas e para minimizar os momentos de dipolo das ligações N-H dos carbazóis. RIO5 e RIO6 também se apresentaram pouco cristalinos e com áreas específicas baixas. Apesar desses resultados, esses materiais ainda podem ser aplicados em eletrônica orgânica por apresentarem estrutura química compatível com tal aplicação. / [en] Two-dimensional materials have functionalization possibilities that make them versatile for various applications such as in electronic devices. The presence of pores in these materials can give new features to them, such as gas adsorption, drug delivery and catalysis. The covalent organic frameworks (COFs) are a new class of crystalline porous organic materials that have been prominent in reticular chemistry. The purpose of this work is to present the synthesis and characterization of four new COFs based on carbazoles, which are a class of compounds used to obtain conductive polymers. The main building block used was 3,6-diamine-9H-carbazole with the aldehyde sources were triformylphloroglucinol, triformylphenol, 1,3,5-tri(4 formylphenyl)benzene and triformylbenzene to obtain RIO2, RIO3, RIO5 and RIO6, respectively. RIO2 and RIO3 are in keto-enamine and imine form, respectively, as well as have low crystallinity and low specific area. Calculus based on Density Functional Theory (DFT) found that these COFs present their sheets displaced and rotated due to electrostatic interactions and to minimize the dipole moments of the N-H bonds of carbazoles. In an attempt to avoid the absence of pores, RIO5 and RIO6 materials were synthesized, however these COFs also performed poorly crystalline and with low specific areas. Despite these results, these materials can also be applied in organic electronics by presenting chemical structure compatible with such application.
2

Síntese de derivados carbazólicos e beta-carbolínicos e avaliação da atividade antimalárica in vitro

Montoia, Andreia, 92-98243-2460 04 October 2017 (has links)
Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-03-02T15:45:37Z No. of bitstreams: 2 Reprodução Não Autorizada.pdf: 47716 bytes, checksum: 0353d988c60b584cfc9978721c498a11 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-03-02T15:45:50Z (GMT) No. of bitstreams: 2 Reprodução Não Autorizada.pdf: 47716 bytes, checksum: 0353d988c60b584cfc9978721c498a11 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-03-02T15:45:50Z (GMT). No. of bitstreams: 2 Reprodução Não Autorizada.pdf: 47716 bytes, checksum: 0353d988c60b584cfc9978721c498a11 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-10-04 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The steady increase in the number of current drug resistance cases used without malaria treatment has encouraged studies on a discovery of potentially active new drugs. In previous work by LAPAAM / INPA has revealed the in vitro and in vivo antimalarial activity of indole alkaloids, such as elipticine, olivacin and derivatives. The great challenge has been found other indolic structures, which are easier to obtain and which present similar or superior antimalarial activity as found in these structures. In this search, nucleic acid tricyclic derivatives obtained from carbazolic and -carbolinic skeletons were synthesized and attributes against in vitro assays. In total, twenty-three derivatives were synthesized, of which eighteen were evaluated in vitro biological assays against K1 P. falciparum strains and cytotoxicity in non-tumor cells (MRC-5). In addition were submitted to the tests five commercial substances harmine (24), harmane (25), harmaline (27) and carbazole (29). As the main reactions for the nitration, demethylation, formation of salts through hydrogen chloride bubbling, condensation reaction of Pictet-Splenger and alkylation, a quality formed by the unpublished compound in the 9-(2,3-dihydroxy)-harmano (25.1). Among the derivatives submitted antimalarial assays, 3-nitrocarbazole (29.4), O-acetyl-harmol (26.1) and the harmine salt HCl (24.4) were the most active with IC50 8,87 M, 12,2 M and IC50 19,31 M, respectively. The 8-nitroharmano (25.2) and the 9-(2,3-dihydropropyl)-harmane (25.1) had their activity potentiated with IC50 values lower than the harmane. And more active commercial substances harmaline with IC50 14,7 M and the norharman with IC50 17.67 M. According to the factory, there is no concentration of 50 g / mL, except for 6-nitro-harmano (25.3) and O-acetyl-harmol, whose lower viability is less than 25%. / O constante aumento no número de casos de resistências aos medicamentos atuais utilizados no tratamento da malária tem incentivado estudos sobre a descoberta de novas drogas potencialmente ativas. Trabalhos anteriores realizados pelo LAPAAM/INPA revelaram a atividade antimalárica in vitro e também in vivo de alcaloides indólicos, tais como elipticina, olivacina e derivados. O grande desafio tem sido encontrar outras estruturas indólicas, de mais fácil obtenção e que apresente atividade antimalárica similar ou superior às encontradas nestas estruturas. Nessa busca, derivados tricíclicos com núcleo indólicos obtidos a partir esqueletos carbazólicos e -carbolínicos foram sintetizados e avaliados frente a ensaios in vitro. No total foram sintetizados vinte e três derivados, dos quais dezoito foram avaliados em ensaios biológicos in vitro contra cepas K1 de P. falciparum e citotoxidade em células não tumorais (MRC-5). Também foram submetidos aos ensaios, as cinco substâncias comerciais norhamano (23), harmina (24), harmano (25), harmalina (27) e carbazol (29). As principais reações utilizadas foram nitração, desmetilação, formação de sais através do borbulhamento de cloreto de hidrogênio, reação de condensação de Pictet-Splenger e alquilação, a qual formou o composto inédito na literatura 9-(2,3-diidroxi)-harmano (25.1). Entre os derivados submetidos aos ensaios antimaláricos, o 3-nitro-carbazol (29.2), O-acetil-harmol (26.1) e o sal de harmina.HCl (24.4) foram os mais ativos com CI50 8,87 M , 12,2 M e CI50 19,31 M, respectivamente. O 8-nitroharmano (25.2) e o 9-(2,3-diidropropil)-harmano (25.1) tiveram sua atividade potencializada com valores de IC50 inferiores ao harmano. E entre as substâncias comerciais, as mais ativas foram a harmalina com CI50 14,7 M e o norharmano com CI50 17,67 M. De maneira geral todos as estruturas estudas neste trabalho apresentaram baixa toxicidade em células normais com viablidade maior que 50 %, na concentração de 50 g/mL, com exceção do 6-nitro-harmano (25.3) e do O-acetil-harmol, cujas viablidades foram inferiores a 25%.
3

Iron-mediated Synthesis of the Antiostatins

Knott, Kerstin 20 March 2009 (has links) (PDF)
Within this thesis the first total syntheses of eight biologically active natural products from the family of carbazole alkaloids, antiostatins A1 to A4 and B2 to B5, were established. Spectroscopic data of the synthesised natural products are in good agreement with the isolated antiostatins from Streptomyces cyaneus 2007-SV1, which confirms the molecular structures assigned to the natural products. The total synthesis of the antiostatins A1 to A4 and B2 to B5 were achieved employing the iron-mediated synthesis to form the carbazole nucleus from a cyclohexadienylium iron salt and appropriate arylamines. This transition metal-mediated approach could be applied to all antiostatins in excellent yields. The antiostatins A1-4 and B2-5 represent the first carbazole alkaloids with an acetamide or substituted biuret chain. Introduction of the sophisticated substituents proceeded selectively on C-4 in high yields. Antiostatins A1 to A4 and B2 to B5 could be synthesised over eight steps from a tricarbonyliron-coordinated cyclohexadienylium salt. The overall yields are in the range of 31 – 63%.
4

Synthese halogenierter Carbazole und Totalsynthese der Amaryllisalkaloide Pratosin und Hippadin

Kirst, Juliane 14 July 2009 (has links) (PDF)
Während meiner Dissertation beschäftigte ich mich mit der Synthese von polyhalogenierten Carbazolderivaten. Das Carbazolgerüst wurde über den Palladiumvermittelten, bestehend aus Buchwald-Hartwig-Aminierung und oxidativer Cyclisierung, aufgebaut. Die Halogensubstituenten wurden entweder am Carbazol eingeführt oder bereits über die Startmoleküle in die Synthese eingebracht. Somit konnten verschiedene halogenierte halogenierte Derivate synthetisiert werden. Diese Verbindungen konnten in einer Kooperation mit Herrn Prof. Gutzeit aus der Fachrichtung Biologie der TU Dresden auf ihre Aktivität in der Inhibierung der Myosin ATPase untersucht werden. Dabei wurde ein tribromiertes 1-Hydroxycarbazol als wirksamer Inhibitor identifiziert. Der zweite Teil der Promotion umfasst die Darstellung der Amaryllisalkaloide Pratosin und Hippadin, sowie der auf diesem Weg ebenfalls zugänglichen Naturstoffe Assoanin, Oxoassoanin, Anhydrolycorin-7-on und deren Naturstoffanaloga Anhydrolycorin. Die Synthese wurde auf zwei verschiedenen Wegen durchgeführt und beinhaltet als Schlüsselreaktionen die Eisenvermittelte C-C und C-N Bindungsbildung, sowie die Palladiumvermittelte Biarylkupplung. / This thesis is about my research study of the synthesis of polyhalogenated carbazoles. The skeletal structure of the carbazoles are easily assembled by palladium(0)-catalyzed Buchwald-Hartwig coupling and palladium(II)-mediated oxidative cyclisation. Through cooperation with Prof. Gutzeit many different halogenated carbazole derivatives could be analyzed concerning the activity of the inhibition of myosin ATPase. The tribrominated 1-Hydroxycarbazole was identified as sn effective inhibitor. The second part of my thesis includes the total synthesis of amaryllidaceae alkaloids pratosine, oxoassoanine, assoanine, hippadine, anhydrolycorinone and anhydrolycorine. The synthesis was accomplished by two different pathways which include the Iron-mediated C-C and C-N bond formation and intramolecular palladium-catalysed biaryl coupling reaction as the key steps.
5

Química de alcaloides carbazólicos: síntese de Claurailas e de biblioteca de análogos estruturais / Carbazole alkaloids chemistry: synthesis of Claurailas and library of analogues

Fumagalli, Fernando 17 April 2015 (has links)
Compostos heterociclos estão muito presentes em nossas vidas, desde processos biológicos até em fármacos. Dentre esses compostos, os carbazóis, vem ultimamente se mostrando promissores como alternativa terapêutica para diversas doenças, principalmente para o câncer. Muitos carbazóis são produtos naturais, como é o caso das Claurailas A-D. Baseando-se na estrutura da Clauraila A, esse trabalho propôs o desenvolvimento de uma biblioteca de análogos desse alcaloide a fim de prospecção biológica. Para a síntese da Clauraila A foram estudadas condições ideais da ciclodeidrogenação da diarilamina precursora desse alcaloide, através da reação de Åkermark-Knölker. Para a obtenção dessa diarilamina, foi realizado uma otimização da reação de aminação de Buchwald-Hartwig. Com o processo otimizado, foram obtidos diversos carbazóis, com diferentes padrões de substituição, em rendimentos bons à moderados, entre eles estão os produtos naturais 6-metoximurraianine e Clausenal. O rendimento global obtido na síntese desses produtos naturais e da Clauraila A são semelhantes aos previamente descritos na literatura, no entanto, em nosso trabalho foi realizada a síntese deste alcaloide em número reduzido de etapas. Durante o processo de otimização da reação de Åkermark-Knölker foi demonstrado, pela primeira vez, o uso de acetilacetonato de paládio como fonte de paládio II alternativa ao acetato de paládio. Além disso, com esses resultados foi possível inferir o possível mecanismo dessa reação. Adicionalmente, após tentativas por diversas alternativas sintéticas, foram obtidos compostos dimetilcromenos a partir de aminofenóis utilizando prenal e ácido fenilborônico, que podem ser úteis na síntese de outros carbazóis, como a Clauraila B. / Heterocyclic molecules are very important class of compounds in biological processes and drugs designing. Among all of them, carbazoles show great applicability for treatment of several diseases, especially against cancer. Many carbazoles are natural products, and one of our interests is Clauraila A. This work is based on the Clauraila A structure to development of a library of carbazoles for biological applications. The optimal conditions of the Åkermark-Knölker cyclodehydrogenation of diarylamine was studied to obtaind the carbazole core. The diarylamines were obtained by the optimized Buchwald-Hartwig amination reaction. This synthetic strategy was used to obtain the range of carbazoles, with different substituents in good and moderate yields, including natural products 6-methoxymurrayanine and Clausenal. The overall yield obtained in the synthesis of the natural products were similar to those previously described in the literature, however, unlike the literature our synthesis involved a reduced number of steps to obtain the desired product. In the optimization step of Åkermark-Knölker reaction, we first applied palladium (II) acetylacetonate instead of palladium (II) acetate. Moreover, with the achieved results the possible mechanism of this reaction was proposed. Additionally, after several attempts, dimethylchromenos were obtained from aminophenols using prenal and phenylboronic acid, which will be useful in the synthesis of other carbazoles, such as Clauraila B.
6

Química de alcaloides carbazólicos: síntese de Claurailas e de biblioteca de análogos estruturais / Carbazole alkaloids chemistry: synthesis of Claurailas and library of analogues

Fernando Fumagalli 17 April 2015 (has links)
Compostos heterociclos estão muito presentes em nossas vidas, desde processos biológicos até em fármacos. Dentre esses compostos, os carbazóis, vem ultimamente se mostrando promissores como alternativa terapêutica para diversas doenças, principalmente para o câncer. Muitos carbazóis são produtos naturais, como é o caso das Claurailas A-D. Baseando-se na estrutura da Clauraila A, esse trabalho propôs o desenvolvimento de uma biblioteca de análogos desse alcaloide a fim de prospecção biológica. Para a síntese da Clauraila A foram estudadas condições ideais da ciclodeidrogenação da diarilamina precursora desse alcaloide, através da reação de Åkermark-Knölker. Para a obtenção dessa diarilamina, foi realizado uma otimização da reação de aminação de Buchwald-Hartwig. Com o processo otimizado, foram obtidos diversos carbazóis, com diferentes padrões de substituição, em rendimentos bons à moderados, entre eles estão os produtos naturais 6-metoximurraianine e Clausenal. O rendimento global obtido na síntese desses produtos naturais e da Clauraila A são semelhantes aos previamente descritos na literatura, no entanto, em nosso trabalho foi realizada a síntese deste alcaloide em número reduzido de etapas. Durante o processo de otimização da reação de Åkermark-Knölker foi demonstrado, pela primeira vez, o uso de acetilacetonato de paládio como fonte de paládio II alternativa ao acetato de paládio. Além disso, com esses resultados foi possível inferir o possível mecanismo dessa reação. Adicionalmente, após tentativas por diversas alternativas sintéticas, foram obtidos compostos dimetilcromenos a partir de aminofenóis utilizando prenal e ácido fenilborônico, que podem ser úteis na síntese de outros carbazóis, como a Clauraila B. / Heterocyclic molecules are very important class of compounds in biological processes and drugs designing. Among all of them, carbazoles show great applicability for treatment of several diseases, especially against cancer. Many carbazoles are natural products, and one of our interests is Clauraila A. This work is based on the Clauraila A structure to development of a library of carbazoles for biological applications. The optimal conditions of the Åkermark-Knölker cyclodehydrogenation of diarylamine was studied to obtaind the carbazole core. The diarylamines were obtained by the optimized Buchwald-Hartwig amination reaction. This synthetic strategy was used to obtain the range of carbazoles, with different substituents in good and moderate yields, including natural products 6-methoxymurrayanine and Clausenal. The overall yield obtained in the synthesis of the natural products were similar to those previously described in the literature, however, unlike the literature our synthesis involved a reduced number of steps to obtain the desired product. In the optimization step of Åkermark-Knölker reaction, we first applied palladium (II) acetylacetonate instead of palladium (II) acetate. Moreover, with the achieved results the possible mechanism of this reaction was proposed. Additionally, after several attempts, dimethylchromenos were obtained from aminophenols using prenal and phenylboronic acid, which will be useful in the synthesis of other carbazoles, such as Clauraila B.
7

Synthese halogenierter Carbazole und Totalsynthese der Amaryllisalkaloide Pratosin und Hippadin

Kirst, Juliane 01 July 2009 (has links)
Während meiner Dissertation beschäftigte ich mich mit der Synthese von polyhalogenierten Carbazolderivaten. Das Carbazolgerüst wurde über den Palladiumvermittelten, bestehend aus Buchwald-Hartwig-Aminierung und oxidativer Cyclisierung, aufgebaut. Die Halogensubstituenten wurden entweder am Carbazol eingeführt oder bereits über die Startmoleküle in die Synthese eingebracht. Somit konnten verschiedene halogenierte halogenierte Derivate synthetisiert werden. Diese Verbindungen konnten in einer Kooperation mit Herrn Prof. Gutzeit aus der Fachrichtung Biologie der TU Dresden auf ihre Aktivität in der Inhibierung der Myosin ATPase untersucht werden. Dabei wurde ein tribromiertes 1-Hydroxycarbazol als wirksamer Inhibitor identifiziert. Der zweite Teil der Promotion umfasst die Darstellung der Amaryllisalkaloide Pratosin und Hippadin, sowie der auf diesem Weg ebenfalls zugänglichen Naturstoffe Assoanin, Oxoassoanin, Anhydrolycorin-7-on und deren Naturstoffanaloga Anhydrolycorin. Die Synthese wurde auf zwei verschiedenen Wegen durchgeführt und beinhaltet als Schlüsselreaktionen die Eisenvermittelte C-C und C-N Bindungsbildung, sowie die Palladiumvermittelte Biarylkupplung. / This thesis is about my research study of the synthesis of polyhalogenated carbazoles. The skeletal structure of the carbazoles are easily assembled by palladium(0)-catalyzed Buchwald-Hartwig coupling and palladium(II)-mediated oxidative cyclisation. Through cooperation with Prof. Gutzeit many different halogenated carbazole derivatives could be analyzed concerning the activity of the inhibition of myosin ATPase. The tribrominated 1-Hydroxycarbazole was identified as sn effective inhibitor. The second part of my thesis includes the total synthesis of amaryllidaceae alkaloids pratosine, oxoassoanine, assoanine, hippadine, anhydrolycorinone and anhydrolycorine. The synthesis was accomplished by two different pathways which include the Iron-mediated C-C and C-N bond formation and intramolecular palladium-catalysed biaryl coupling reaction as the key steps.
8

Iron-mediated Synthesis of the Antiostatins

Knott, Kerstin 16 February 2009 (has links)
Within this thesis the first total syntheses of eight biologically active natural products from the family of carbazole alkaloids, antiostatins A1 to A4 and B2 to B5, were established. Spectroscopic data of the synthesised natural products are in good agreement with the isolated antiostatins from Streptomyces cyaneus 2007-SV1, which confirms the molecular structures assigned to the natural products. The total synthesis of the antiostatins A1 to A4 and B2 to B5 were achieved employing the iron-mediated synthesis to form the carbazole nucleus from a cyclohexadienylium iron salt and appropriate arylamines. This transition metal-mediated approach could be applied to all antiostatins in excellent yields. The antiostatins A1-4 and B2-5 represent the first carbazole alkaloids with an acetamide or substituted biuret chain. Introduction of the sophisticated substituents proceeded selectively on C-4 in high yields. Antiostatins A1 to A4 and B2 to B5 could be synthesised over eight steps from a tricarbonyliron-coordinated cyclohexadienylium salt. The overall yields are in the range of 31 – 63%.
9

The performance characterization of carbazole/dibenzothiophene derivatives in modern OLEDs

Li, Junming 13 January 2017 (has links)
Ein vielversprechendes Design für organische lichtemittierende Dioden (OLEDs) verwendet eine Wirt-Gast-Strategie durch Dispergieren einer kleinen Menge eines hocheffizienten Emitters (der Gast) in eine passende Transportmatrix (der Wirt). Die Aufgabe des Wirts ist den Exzitonentranport zum Emitter sicherzustellen und den Zerfall von Triplet-Exzitonen zu verhindern, und damit eine hohe Bauteilperformance zu erreichen. Die vorliegende Arbeit konzentriert sich auf die Beziehung zwischen Molekülstruktur und optoelektrischer Eigenschaften von Carbazol/Dibenzothiophen-Derivaten. Die Untersuchung umfasst sieben dieser Derivate für den Wirt, bei denen die Carbazoleinheit als Donator und die Dibenzothiopheneinheit als Akzeptor fungiert, wobei beide durch einen oder mehrere Phenylabstandshalter verbunden sind. Diese Wahl der Wirtsmaterialien erlaubt es den Einfluss der erweiterten Phenylabstandshalter und der unterschiedlichen molaren Verhältnisse von Akzeptor zu Donator zu untersuchen. Es ergab sich, dass eine kürzere Phenylabstandshalterlänge die Bauteilperformance durch eine größere Löcher- und Elektronendichte in der Emitterschicht verbessert; und ein 1:1 Carbazol-zu-Dibenzothiophen-Verhältnis der Bauteilperformance zuträglich ist, da es zu einem Ladungsträgergleichgewicht in der Emitterschicht führt. Diese Arbeit zeigt, unter Verwendung dieser Wirtsmaterialien, blaue FIrpic-basierte phosphoreszierende OLEDs (PhOLEDs) und grüne 4CzIPN-basierte thermisch aktivierte verzögerte Phosphoreszenz (TADF) OLEDs. Die blauen PhOLEDs und grünen TADF OLEDs mit mDCP zeigten Effizienzen von 43 cd/A (18.6%) beziehungsweise 66 cd/A (21%). / A particularly interesting organic light-emitting diodes (OLEDs) design adopts a host-guest strategy by dispersing a small amount of highly efficient emitter (the guest) into an appropriate transport matrix (the host). The host is utilized to transfer excitons to the emitter and to prevent triplet exciton quenching, thus high device performance can be achieved. The present thesis focuses on the relationship between the molecular structure and opto-electrical properties of carbazole/dibenzothiophene derivatives. The investigation encompasses seven of these derivatives for the host, in which the carbazole unit acts as a donor and the dibenzothiophene as an acceptor while they are linked through phenyl spacer(s). This choice of host materials enables to assess the impact of extended phenyl spacers and different acceptor to donor molar ratios. It was found that decreasing the phenyl spacer length enhances the device performance due to the larger both hole and electron densities in the emitting layer; and a 1:1 carbazole to dibenzothiophene ratio is favorable for device performance, since it balances the charge carriers in the emitting layer. Using these host materials, the work presented in this thesis demonstrates high-performance blue FIrpic-based phosphorescent OLEDs (PhOLEDs) and green 4CzIPN-based thermally activated delayed fluorescence (TADF) OLEDs. The blue PhOLEDs and green TADF OLEDs with mDCP showed efficiencies of 43 cd/A (18.6%) and 66 cd/A (21%), respectively.
10

Fabrication, caractérisation et étude électrochimique de microcapsules conductrices à base de dérivés carbazole aminés pour la conception de biopiles enzymatiques

Hébert, Mathieu 01 1900 (has links)
L’objectif général de cette thèse est de développer une plateforme d’immobilisation d’enzymes efficace pour application en biopile. Grâce à la microencapsulation ainsi qu’au choix judicieux des matériaux polymériques pour la fabrication de la plateforme d’immobilisation, l’efficacité du transfert électronique entre l’enzyme encapsulée et l’électrode serait amélioré. Du même coup, les biopiles employant cette plateforme d’immobilisation d’enzymes pourrait voir leur puissance délivrée être grandement augmentée et atteindre les niveaux nécessaires à l’alimentation d’implants artificiels pouvant remplacer des organes telque le pancréas, les reins, le sphincter urinaire et le coeur. Dans un premier temps, le p-phénylènediamine a été employé comme substrat pour la caractérisation de la laccase encapsulée dans des microcapsules de poly(éthylèneimine). La diffusion de ce substrat à travers les microcapsules a été étudiée sous diverses conditions par l’entremise de son oxidation électrochimique et enzymatique afin d’en évaluer sa réversibilité et sa stabilité. La voltampérométrie cyclique, l’électrode à disque tournante (rotating disk electrode - RDE) et l’électrode à O2 ont été les techniques employées pour cette étude. Par la suite, la famille des poly(aminocarbazoles) et leurs dérivés a été identifée pour remplacer le poly(éthylèneimine) dans la conception de microcapsules. Ces polymères possèdent sur leurs unités de répétition (mono- ou diamino) des amines primaires qui seraient disponibles lors de la polymérisation interfaciale avec un agent réticulant tel qu’un chlorure de diacide. De plus, le 1,8-diaminocarbazole (unité de répétition) possède, une fois polymérisé, les propriétés électrochimiques recherchées pour un transfert d’électrons efficace entre l’enzyme et l’électrode. Il a toutefois été nécessaire de développer une route de synthèse afin d’obtenir le 1,8-diaminocarbazole puisque le protocole de synthèse disponible dans la littérature a été jugé non viable pour être utilisé à grande échelle. De plus, aucun protocole de synthèse pour obtenir du poly(1,8-diaminocarbazole) directement n’a été trouvé. Ainsi, deux isomères de structure (1,6 et 1,8-diaminocarbazole) ont pu être synthétisés en deux étapes. La première étape consistait en une substitution électrophile du 3,6-dibromocarbazole en positions 1,8 et/ou 1,6 par des groupements nitro. Par la suite, une réaction de déhalogénation réductive à été réalisée en utilisant le Et3N et 10% Pd/C comme catalyseur dans le méthanol sous atmosphère d’hydrogène. De plus, lors de la première étape de synthèse, le composé 3,6-dibromo-1-nitro-carbazole a été obtenu; un monomère clé pour la synthèse du copolymère conducteur employé. Finalement, la fabrication de microcapsules conductrices a été réalisée en incorporant le copolymère poly[(9H-octylcarbazol-3,6-diyl)-alt-co-(2-amino-9H-carbazol-3,6-diyl)] au PEI. Ce copolymère a pu être synthétisé en grande quantité pour en permettre son utilisation lors de la fabrication de microcapsules. Son comportement électrochimique s’apparentait à celui du poly(1,8-diaminocarbazole). Ces microcapsules, avec laccase encapsulée, sont suffisamment perméables au PPD pour permettre une activité enzymatique détectable par électrode à O2. Par la suite, la modification de la surface d’une électrode de platine a pu être réalisée en utilisant ces microcapsules pour l’obtention d’une bioélectrode. Ainsi, la validité de cette plateforme d’immobilisation d’enzymes développée, au cours de cette thèse, a été démontrée par le biais de l’augmentation de l’efficacité du transfert électronique entre l’enzyme encapsulée et l’électrode. / The main objective of this thesis is the development of a conductive enzyme immobilisation template for laccase through microencapsulation allowing an efficient electron transfer between the enzyme and the electrode for application in biofuel cells. First, p-phenylenediamine was used as substrate for the characterisation of the microencapsulated laccase. The diffusion of this substrate through the microcapsules was studied under various conditions by means of its electrochemical and enzymatic oxidation processes in order to assess its reversibility and stability. Cyclic voltammetry, rotating disk electrode and Clark electrode were the techniques used in this study. Moreover, poly(aminocarbazole) compounds and their derivatives were identified to replace poly(ethyleneimine) in the fabrication of the microcapsules. These polymers exhibit primary amines (mono- or di-amino) that could be available for an interfacial polymerisation using a cross-linker agent. Also, the monomer 1,8-diaminocarbazole presents the desired electrochemical propreties for an efficient electron transfer between the enzyme and the electrode. Therefore, a synthetic pathway was developed in order to synthesise this monomer since the available literature protocol was considered inappropriate for large scale synthesis. As for the direct synthesis of the poly(1,8-diaminocarbazole), to our knowledge, there is no protocol currently available. Two structural isomers (1,6 and 1,8-diaminocarbazole) were thus synthesised in two steps. The first step consists in the electrophilic substitution of 3,6-dibromocarbazole in 1,8 and/or 1,6 positions by nitro groups. This step was followed by a dehydrodehalogenation reaction that comes along with reduction of nitro to amino functions using Et3N and 10% Pd/C as the catalyst in methanol under H2 flux. During the first step, the 3,6-dibromo-1-nitro-carbazole was also obtained and appeared to be an efficient monomer in the synthesis of the desired conductive copolymer. Finally, the fabrication of the conductive microcapsules was realised by adding the copolymer poly[(9H-octylcarbazol-3,6-diyl)-alt-co-(2-amino-9H-carbazol-3,6-diyl)] to the PEI. This copolymer was synthesised in large quantities, which allowed its use in the design of microcapsules. Its electrochemical behaviour was similar in many ways to the one of poly(1,8-diaminocarbazole). These conductive microcapsules were then used to modify the surface of a platinum electrode to fabricate the bioelectrode. The main objective of this project was achieved through this final step.

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