Push-Pull Molecule Polarization through Pentafluorosulfanyl Group

Byla provedena literární rešerše zaměřená na zavedení pentafluorsulfanylové (SF5) skupiny do struktury (hetero)aromatických systémů a jejich využití v materiálové chemii. Byly nalezeny tři obecné postupy jejich příprav. Vedle medicinálního a agrochemického využití SF5 derivátů jsou jejich optoelektronické aplikace limitovány na tekuté krystaly, luminiscenční materiály, spínače a push pull chromofory. V experimentální části byly syntetizovány dvě D-pí-A a čtyři D(-pí- A)3 push-pull molekuly s pentafluorsulfanylovou akceptorní jednotkou a aminoskupinu jako elektrondonorní částí. Vlastnosti cílových chromoforů byly modulovány změnou pí- konjugované cesty sestávající z kombinace 1,4 fenylových a acetylenických jednotek, polohou a počtem SF5 skupin a celkovým rozložením chromoforu (lineární a tripodální). Všechny molekuly byly charakterizovány sérií analytických měření (NMR, IČ, MS spektroskopie a RTG analýza) a byla měřena jejich UV-Vis spektra a termické chování. Z výsledků analýz byly vyvozeny základní vztahy typu struktura vlastnosti.A literature search focusing on introducing pentafluorosulfanyl (SF5) group into a structure of (hetero)aromatic systems and their utilization in material chemistry has been carried out. Three general synthetic methods leading to these compounds have been identified. Beside medicinal chemistry and agrochemical use of SF5 derivatives, their optoelectronic applications are limited to liquid crystals, luminescent materials, switches and push-pull chromophores. In the experimental part, two D -pí- A and four D(-pí- A)3 push-pull molecules bearing pentafluorosulfanyl acceptor(s) and amino donor were prepared. Properties of target chromophores were modulated by changing the ?-conjugated path consisting of a combination of 1,4-phenylene and acetylenic units, position and number of SF5 groups, and chromophore overall arrangement (linear and tripodal). All target derivatives were characterized by a series of analytical tools (such as NMR, IR, mass spectroscopy and X-ray analysis) as well as by UV-Vis absorption spectra and differential scanning calorimetry. Fundamental structure property relationships were elucidated from the obtained results.Fakulta chemicko-technologick

Organické a organokovové heterocyklické luminiscentní materiály pro aplikaci v OLED

Od roku 1987, kdy byla C. W. Tangem a S. V. Slykem (ve společnosti Eastman Kodak) vyrobena první organická světlo emitující dioda (OLED), zájem o vývoj nových světlo emitujících zařízeních s organickými materiály neustále vzrůstá. V předložené disertační práci jsou diskutovány organické a organokovové luminofory nesoucí pyrimidinový heterocyklus jako elektronakceptorní jednotku. Byly připraveny tři série derivátů s odlišnými strukturními vlastnostmi a to (i) 2,4-di(arylvinyl)- a 2,4,6-tri(arylvinyl)pyrimidiny se stejnými či různými okrajovými elektrondonorními skupinami, (ii) 4-arylvinyl- a 4,6-di(arylvinyl)pyrimidiny s fenylakridinovou vytočenou strukturou v poloze 2 pyrimidinového jádra a (iii) platinové komplexy nesoucí 2-fenylpyrimidinové cyklometalující ligandy. Byly měřeny fotoluminiscenční vlastnosti všech cílových derivátů a z nich vyvozeny základní vztahy struktura-fotoluminiscenční vlastnosti, které byly důkladně diskutovány. Bylo pozorováno několik zajímavých luminiscentních úkazů, jako protonací modulovatelná emise, agregací vyvolaná emise, dvojitá emise, emise v pevném stavu nebo emise bílého světla, pro některé deriváty napříč všemi sériemi látek.Since 1987, when the first organic light-emitting diode (OLED) was prepared by C. W. Tang and S. V. Slyke (Eastman Kodak company), there has been a great interest in the development of lighting devices based on organic materials. In this dissertation, organic and organometallic luminophores bearing pyrimidine heterocycle as electron-withdrawing moiety are discussed. Three series with different structural features were prepared: (i) 2,4-di(arylvinyl)- and 2,4,6-tri(arylvinyl)pyrimidines with identical or different peripheral electron-donating groups, (ii) 4-arylvinyl- and 4,6-di(arylvinyl)pyrimidines with twisted phenylacridan structure in position 2 of pyrimidine ring and (iii) 2-phenylpyrimidine cyclometalated platinum (II) complexes. Photoluminescence properties of all final derivatives were measured. Structure-photoluminescence relationships within each series were drawn from these results and thoroughly discussed. Interesting luminescence phenomena, such as tuneable emission by protonation, aggregation-induced emission, dual emission, solid-state emission or white light emission, were observed for certain derivatives across the series.Fakulta chemicko-technologickáDokončená práce s úspěšnou obhajobo

Matériaux luminescents hétérocycliques organiques et organométalliques : vers des applications OLEDs

Since 1987, when the first organic light-emitting diode (OLED) was prepared by C. W. Tang and S. V. Slyke (Eastman Kodak company), there has been a great interest in the development of lighting devices based on organic materials. In this dissertation, organic and organometallic luminophores bearing pyrimidine heterocycle as electron-withdrawing moiety are discussed. Three series with different structural features were prepared: (i) 2,4-di(arylvinyl)- and 2,4,6 tri(arylvinyl)pyrimidines with identical or different peripheral electron-donating groups, (ii) 4-arylvinyl- and 4,6-di(arylvinyl)pyrimidines with twisted phenylacridan structure in position 2 of pyrimidine ring and (iii) 2 phenylpyrimidine cyclometalated platinum (II) complexes. Photoluminescence properties of all final derivatives were measured. Structure-photoluminescence relationships within each series were drawn from these results and thoroughly discussed. Interesting luminescence phenomena, such as tuneable emission by protonation, aggregation-induced emission, dual emission, solid-state emission or white light emission, were observed for certain derivatives across the series.Depuis 1987, date à laquelle la première diode électroluminescente organique (OLED) a été préparée par C. W. Tang et S. V. Slyke (Eastman Kodak company), il y a eu un grand intérêt pour le développement de dispositifs d'éclairage à base de matériaux organiques. Dans ce manuscrit, des luminophores organiques et organométalliques portant un hétérocycle pyrimidine en tant que groupement attracteur d'électrons sont discutés. Trois séries avec des caractéristiques structurelles différentes ont été préparées: (i) Une série de 2,4-di (arylvinyl)- et de 2,4,6-tri(arylvinyl)pyrimidines avec des groupes électro-donneurs périphériques identiques ou différents, (ii) Une série de 4-arylvinyl- et de 4,6-di(arylvinyl)pyrimidines portant un groupement phénylacridine torsadé en position 2 du cycle pyrimidine (iii) Des complexes de platine (II) cyclométalé à base de 2-phénylpyrimidine. Les propriétés de photoluminescence de tous les dérivés finaux ont été mesurées. Des relations structure-photoluminescence au sein de chaque série ont été tirées de ces résultats et discutées en détail. Des phénomènes de luminescence intéressants, tels que l'émission accordable par protonation, l'émission induite par l'agrégation, l’émission duale, l'émission à l'état solide ou l'émission de lumière blanche, ont été observés pour certains de ces dérivés

Organic and organometallic heterocyclic luminescent materials : towards OLED applications

Depuis 1987, date à laquelle la première diode électroluminescente organique (OLED) a été préparée par C. W. Tang et S. V. Slyke (Eastman Kodak company), il y a eu un grand intérêt pour le développement de dispositifs d'éclairage à base de matériaux organiques. Dans ce manuscrit, des luminophores organiques et organométalliques portant un hétérocycle pyrimidine en tant que groupement attracteur d'électrons sont discutés. Trois séries avec des caractéristiques structurelles différentes ont été préparées: (i) Une série de 2,4-di (arylvinyl)- et de 2,4,6-tri(arylvinyl)pyrimidines avec des groupes électro-donneurs périphériques identiques ou différents, (ii) Une série de 4-arylvinyl- et de 4,6-di(arylvinyl)pyrimidines portant un groupement phénylacridine torsadé en position 2 du cycle pyrimidine (iii) Des complexes de platine (II) cyclométalé à base de 2-phénylpyrimidine. Les propriétés de photoluminescence de tous les dérivés finaux ont été mesurées. Des relations structure-photoluminescence au sein de chaque série ont été tirées de ces résultats et discutées en détail. Des phénomènes de luminescence intéressants, tels que l'émission accordable par protonation, l'émission induite par l'agrégation, l’émission duale, l'émission à l'état solide ou l'émission de lumière blanche, ont été observés pour certains de ces dérivés.Since 1987, when the first organic light-emitting diode (OLED) was prepared by C. W. Tang and S. V. Slyke (Eastman Kodak company), there has been a great interest in the development of lighting devices based on organic materials. In this dissertation, organic and organometallic luminophores bearing pyrimidine heterocycle as electron-withdrawing moiety are discussed. Three series with different structural features were prepared: (i) 2,4-di(arylvinyl)- and 2,4,6 tri(arylvinyl)pyrimidines with identical or different peripheral electron-donating groups, (ii) 4-arylvinyl- and 4,6-di(arylvinyl)pyrimidines with twisted phenylacridan structure in position 2 of pyrimidine ring and (iii) 2 phenylpyrimidine cyclometalated platinum (II) complexes. Photoluminescence properties of all final derivatives were measured. Structure-photoluminescence relationships within each series were drawn from these results and thoroughly discussed. Interesting luminescence phenomena, such as tuneable emission by protonation, aggregation-induced emission, dual emission, solid-state emission or white light emission, were observed for certain derivatives across the series

Electron Withdrawing Properties of Pentafluorosulfanyl Group

Byla provedena literární rešerše syntéz a využití pí-konjugovaných systémů nesoucích pentafloursulfanylovou skupinu jako akceptorní část. V teoretické části bylo pojednáno jednak o pí-konjugovaných systémech v push-pull uspořádání, možnostech zavedení SF5 skupiny na sp2-hybridizované atomy uhlíku a rovněž o praktickém využití takových sloučenin. V praktické části byly syntetizovány čtyři D-pí-A molekuly s pentafluorsulfanylovou akceptorní jednotkou pomocí cross-coupling reakcí. Syntetizované molekuly obsahují N,N-dimethylamino skupiny jako elektron donor a různě variovaný pí můstek. Všechny molekuly byly charakterizovány sérií analytických měření (bod tání, NMR, MS a RTG) a rovněž byla změřena jejich UV/Vis spektra, ze kterých byly vyvozeny základní vztahy typu struktura-vlastnostiA literature search focusing on the synthesis and use of pi-conjugated systems bearing pentafluorosulfanyl group as electron acceptor moiety has been carried out. The theoretical part describes pi-conjugated systems in push-pull arrangement and the possibilities of introducing SF5 group on to sp2-hybridized carbon atoms. Practical utilization of these molecules is also covered. The experimental part describes synthesis of four D-pi-A molecules with pentafluorosulfanyl acceptor unit by cross-coupling reactions. The synthesized molecules contain an N,N-dimethylamino group as electron donor unit and a pi-conjugated bridge varied in length. All of these molecules were characterized with a series of analytical measurements (melting point, NMR, MS, and RTG) as well as UV/Vis spectra that allowed elucidating the structure-property relationships.Katedra biologických a biochemických vědStudent seznámil komisy se svojí bakalářskou prací.Byl přečten posudek BP. Student reagoval na vaechny otázky

Efekt protonace na dynamiku excitovaného stavu pyrimidinových chromoforů

The effect of protonation on the photophysics and especially on the excited state dynamics of two pyrimidine chromophores, bearing the A-(pi-D)(2) and A-(pi-D)(3) structure, is studied by means of fs-ps and ns time resolved fluorescence spectroscopy. Three different acids, namely camphorsulphonic (CSA), acetic (AcOH) and trifluoroacetic acid (TFA) were used. The chromophores bear the pyrimidine electron deficient heterocycle as electron-withdrawing group, used as protonation site, as well as diphenylamino electron donors. Protonation is revealed through the emergence of red-shifted absorption and fluorescence bands accompanied by a quenching of the fluorescence of the neutral molecules. Time-resolved dynamics reveal that protonation with CSA and TFA do not influence the excited state lifetime of the chromophores, pointing to a static quenching process. On the other hand, the lifetime is decreased upon protonation with AcOH. Further investigation based on the Stern-Vollmer plots showed that addition of AcOH leads to both dynamic and static quenching.Byl studován efekt protonace na fotofyziku dvou pyrimidinových chromoforů prostřednictvím fluorescenční spektroskopie. Byly využity tři kyseliny, kafrsulfonová, octová a trifluoroctová

V-Shaped Methylpyrimidinium Chromophores for Nonlinear Optics

International audienceA series of four V-shaped methylpyrimidinium salts bearing diphenylamino-electron-donating groups appended at various pyrimidine positions were designed. These chromophores were obtained by regioselective N(1) monomethylation by methyl methanesulfonate of the pyrimidine core. Linear optical properties were studied experimentally and electronic properties were further completed by (TD)-DFT calculations. The second-order nonlinear optical (NLO) properties were also studied using electric field induced second harmonic generation (EFISH) method in chloroform, and all pyrimidinium salts exhibited μβ(0) >1000×10(-48)  esu. The 2,4-disubstituted pyrimidinium core is preferred over 4,6-disubstitution as it enhances the NLO response and increases the dipole moment. (E,E)-2,4-Bis[4-(diphenylamino)styryl]-1-methylpyrimidin-1-ium methanesulfonate appears to be the best NLO-phore in chloroform in the series (μβ(0) =2500×10(-48)  esu) and a figure of merit μβ(0) /MW=3.4 10(-48)  esu mol g(-1)

Influence of Donor-Substituents on Triphenylamine Chromophores Bearing Pyridine Fragments

International audienceEfficient synthetic routes that combine different palladium-catalyzed cross-coupling reactions have been developed for the preparation of a new family of push-pull derivatives in which pyridine was used as the acceptor group and different para-substituted diphenylamines as the donor groups. All compounds showed absorption in the UV/Vis region and blue-green emission with high quantum yields. Significant red shifts were observed in the absorption and fluorescence emission maxima on increasing the electron-donating ability of the substituents or on incorporating a pi-conjugated linker. This finding can be explained on the basis of enhanced intramolecular charge transfer (ICT). Strong emission solvatochromism confirmed the formation of an intramolecular charge-separated emitting state. The HOMO-LUMO energy gaps have been estimated by experimental electrochemical measurements and the results were interpreted with the aid of DFT calculations. The thermal behavior of all materials has also been studied by differential scanning calorimetry

Fotofyzikální vlastnosti 9,9-dimethylakridanem substituovaných fenylstyrylpyrimidinů – charakteristiky dlouhotrvající intramolekulární charge-transfer fluorescence a agregací indukované emise

Six pyrimidine-based push-pull systems substituted at positions C2 and C4/6 with phenylacridan and styryl moieties, employing methoxy or N,N-diphenylamino donors, have been designed and synthesized through cross-coupling and Knoevenagel reactions. X-ray analysis confirmed that the molecular structure featured the acridan moiety arranged perpendicularly to the residual pi system. Photophysical studies revealed significant differences between the methoxy and N,N-diphenylamino chromophores. Solvatochromic studies revealed that the methoxy derivatives showed dual emission in polar solvents. Time-resolved spectroscopy revealed that the higher energy band involved very fast (<80 ps) fluorescence, whereas the lower energy one included long components (approximate to 30 ns) due to long-lived intramolecular charge-transfer fluorescence. In contrast to N,N-diphenylamino chromophores, the methoxy derivatives also showed aggregation-induced emission in mixtures of THF/water, as well as dual emission in thin films, covering almost the whole visible spectrum with corresponding chromaticity coordinates not far from that of pure white light. These properties render the methoxy derivatives as very promising organic materials for white organic light-emitting diodes.Cross-couplingovými reakcemi a Knoevenagelovou kondenzací bylo připraveno šest push-pull molekul na bázi pyrimidinu substituovaných v polohách C2 a C4/6 fenylakridanem a styrenovými fragmenty, dekorované methoxy nebo N,N-difenylamino substituenty jako donory. X-ray analýzy potvrdily strukturu látek, akridanová část je orientována kolmo ke zbývajícími pi-systému. Fotofyzikální studie potvrdily významné rozdíly mezi methoxy s N,N-difenylamino chromofory. Při solvatochromních studiích vykazovaly methoxy deriváty duální emisi v polárních rozpouštědlech

Branching effect on the linear and nonlinear optical properties of styrylpyrimidines

International audienceThis contribution aims at investigating the branching effect on the steady state, time resolved fluorescence and two-photon absorption (2PA) properties of dimethylamino and diphenylamino substituted styrylpyrimidine derivatives, by means of a combined experimental and theoretical study. In contrast to classical branched molecules with a triphenylamine central core and electron accepting groups at the periphery, here, branched molecules with reverse topology and different symmetries are examined, namely a styrylpyrimidine group is used as the electron withdrawing core and dimethylamino or diphenylamino donors are incorporated at the periphery. Besides, compared to the great majority of existing branched systems, the herein studied molecules do not have C3 symmetry. For this reason, the region of the linear and non-linear optical spectra of the two and three branched chromophores is actually similar. Interestingly, while the one-photon absorption spectra of one-branched systems versus two- or three-branched ones are spectrally shifted, there is almost no spectral shift in the main 2PA spectral region. Meanwhile, there is still an enhancement of both linear and nonlinear optical responses. Overall, here we developed a strategy that enhances the 2PA response while maintaining the spectral position. Specifically, 2PA cross section values as high as 500 GM have been obtained for the diphenylamino A–(π–D)3 molecule in dichloromethane