National Repository of Grey Literature 18 records found  1 - 10next  jump to record: Search took 0.01 seconds. 
Electrochemical Properties of Mixed Self-Assembled Monolayers Based on Terpyridine Transition Metal Complexes
Kocábová, Jana ; Nováková Lachmanová, Štěpánka ; Vavrek, František ; Valášek, M. ; Hromadová, Magdaléna
This work presents the electrochemical characterization of mixed self-assembled monolayers\n(SAMs) of [Os(terpy)2]2+ and terpyridine connected by tripodal anchoring groups to the\npolycrystalline gold bead electrode and provides a comparison with SAM based on\n[Os(terpy)2]2+ tripodal molecules without diluting terpyridine tripodal molecules. It is shown\nthat both arrangements enable reproducible preparation of well-defined compact films. The\nelectron transfer rate constant for mixed SAM was determined from cyclic voltammograms\naccording to Laviron’s analysis and compared with the rate constant obtained previously for\nSAM containing only [Os(terpy)2]2+ tripod.
Synthesis and properties of supramolecular polymers
Vitvarová, Tereza ; Vohlídal, Jiří (advisor) ; Jindřich, Jindřich (referee) ; Royal, Guy (referee)
New π-conjugated building blocks (unimers) for metallo-supramolecular polymers (MSPs), whose comprise: (i) substituted phosphole ring surrounded by two thiophene rings as the central block, (ii) 2,2':6',2''-terpyridine-4'-yl (tpy) end-groups as ion-selectors, and (iii) different linkers inserted between the central block and tpy end-groups, are described. Chemical and physical properties of those unimers were studied with attention on correlation between properties and structure of unimers. For example the unimer without linkers shows the UV/vis absorption maximum red shifted about 60 to 100 nm compared to bis(tpy)terthiophenes, which proves that replacing of the thiophene with phosphole unit significantly enhances the delocalization of electrons within the unimer molecule and significant area of absorption spectra can be covered. Introduction of linkers (ethynediyl, ethynediyl-thiophene-2,5-diyl, ethynediyl-1,4-phenylene) has a minor effect on the bandgap energy. All prepared unimers underwent self-assembling process with various metal ions (Co2+ , Cu2+ , Fe2+ , Ni2+ and Zn2+ ) resulting into metallo-supramolecular polymers. Three stages of the assembly of unimers into related MSPs were observed and characterized by absorption, fluorescence spectroscopy and size exclusion chromatography: 1)...
Preparation and properties of bis(terpyridyl)oligofluorenes
Hrma, Martin ; Svoboda, Jan (advisor) ; Drahoňovský, Dušan (referee)
This bachelors thesis deals with the synthesis of bis(terpyridyl)oligofluorenes, that are suitable for the preparation of supramolecular polymers. The main aim was synthesis and characterisation of 7,7'-bis(terpyrid-4'-yl)-9,9,9',9'-tetrakis(6'-bromohexyl)-2,2'-bifluorene. As a starting substance was used commercially available 2-bromofluorene made by Sigma- Aldrich. In the preparation of the final ligand was used three reaction schemes, during the several steps used in the Suzuki coupling, or variations thereof.
Preparation and characterization of bis(terpyridyl)fluorene based polymers
Hrma, Martin ; Svoboda, Jan (advisor) ; Strachota, Adam (referee)
The diploma thesis presents the preparation of ,-bisterpyridinylfluorenes (unimers) containing fluorene unit in the central block either directly attached to terpyridine (tpy) end groups or via 1,4-phenylene or thiophene-2,5-diyl linker. Synthesized unimers were subsequently used for the preparation of metallo-supramolecular polymers with Zn2+ and Fe2+ ions. The prepared unimers were characterized by NMR, IR and HR-MS, their optical properties were investigated using absorption and emission spectroscopy and cyclic voltammetry. Molecular weight distribution for the prepared Fe-polymers was determined by GPC. The number-average degree of polymerization equal to 7 for an equimolar ratio between unimer and Fe2+ in a diluted solution was determined for polymers composed of unimer with thiophene-2,5- diyl linker. By using the viscometric measurements the ongoing constitutional dynamics in solutions of metallo-supramolecular polymers was proven. The overstoichiometric amount of metal ions in solution resulted in equilibrium shortening of the polymer chains together with end-capping of terminal tpy ligands by Mt2+ ions. Unimer with thiophene-2,5-diyl linker exhibited unique properties involving significantly red-shifted absorption and emission maxima, as well as the different behavior during assembling...
Synthesis and properties of supramolecular polymers
Vitvarová, Tereza
New π-conjugated building blocks (unimers) for metallo-supramolecular polymers (MSPs), whose comprise: (i) substituted phosphole ring surrounded by two thiophene rings as the central block, (ii) 2,2':6',2''-terpyridine-4'-yl (tpy) end-groups as ion-selectors, and (iii) different linkers inserted between the central block and tpy end-groups, are described. Chemical and physical properties of those unimers were studied with attention on correlation between properties and structure of unimers. For example the unimer without linkers shows the UV/vis absorption maximum red shifted about 60 to 100 nm compared to bis(tpy)terthiophenes, which proves that replacing of the thiophene with phosphole unit significantly enhances the delocalization of electrons within the unimer molecule and significant area of absorption spectra can be covered. Introduction of linkers (ethynediyl, ethynediyl-thiophene-2,5-diyl, ethynediyl-1,4-phenylene) has a minor effect on the bandgap energy. All prepared unimers underwent self-assembling process with various metal ions (Co2+ , Cu2+ , Fe2+ , Ni2+ and Zn2+ ) resulting into metallo-supramolecular polymers. Three stages of the assembly of unimers into related MSPs were observed and characterized by absorption, fluorescence spectroscopy and size exclusion chromatography: 1)...
Preparation and characterization of bis(terpyridyl)fluorene based polymers
Hrma, Martin
The diploma thesis presents the preparation of ,-bisterpyridinylfluorenes (unimers) containing fluorene unit in the central block either directly attached to terpyridine (tpy) end groups or via 1,4-phenylene or thiophene-2,5-diyl linker. Synthesized unimers were subsequently used for the preparation of metallo-supramolecular polymers with Zn2+ and Fe2+ ions. The prepared unimers were characterized by NMR, IR and HR-MS, their optical properties were investigated using absorption and emission spectroscopy and cyclic voltammetry. Molecular weight distribution for the prepared Fe-polymers was determined by GPC. The number-average degree of polymerization equal to 7 for an equimolar ratio between unimer and Fe2+ in a diluted solution was determined for polymers composed of unimer with thiophene-2,5- diyl linker. By using the viscometric measurements the ongoing constitutional dynamics in solutions of metallo-supramolecular polymers was proven. The overstoichiometric amount of metal ions in solution resulted in equilibrium shortening of the polymer chains together with end-capping of terminal tpy ligands by Mt2+ ions. Unimer with thiophene-2,5-diyl linker exhibited unique properties involving significantly red-shifted absorption and emission maxima, as well as the different behavior during assembling...
Preparation and properties of building blocks of specialty polymers
Šichová, Kristýna
This Diploma Thesis presents results obtained by solution of two partial projects: a) Preparation of monomers from renewable sources using metathesis and tandem hydrogenation catalyzed with ruthenium compounds - project solved during my Erasmus stay at the Université de Rennes 1 in France; b) Preparation and properties of ,-bis(tpy)quarterthiophene oligomers carrying ionic side groups as oligomonomers for polyelectrolyte conjugated dynamers - project solved at the Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague. Project a): Self-metathesis of 1,2-epoxyhex-5-ene (but-3-enyloxirane) and its cross-metathesis with methyl acrylate and acrylonitrile catalyzed with ruthenium compounds as well as tandem design of these metatheses and consecutive hydrogenation of their products by gaseous hydrogen have been optimized. The following influences have been studied and tuned: (i) type of the catalyst (Grubbs, Hoveyda, Zhan) and its concentration and method of dosing, (ii) concentration of reactants and additives, (iii) type of solvent, and (iv) reaction temperature. Reactions were monitored by the GC, GC and MS methods and the products were characterized by the NMR method. Methyl 6,7-epoxyheptanoate (methyl 5-oxiranylpentanoate) obtained by the tandem...
Direct arylation and its application in supramolecular polymer synthesis
Loukotová, Lenka
This thesis is divided into two parts. In the first part there is reported palladium- catalysed regioselective direct arylation of benzofurans with arylsulfonyl chlorides as the coupling partner to C2 carbon. The best reaction conditions of this reaction were investigated, then the influence of various arylsulfonyl chloride substituents to the reaction and finally it is reported direct arylation of C2-arylated benzofuran to C3 carbon to give diarylated benzofuran with different aryl substituents. In the second part, there is reported the synthesis of 2-(hydroxymethyl)-5,7-bis{5- [(2,2':6',2''-terpyridine)-4'-yl]thiophen-2-yl}-2,3-dihydrothieno[3,4-b][1,4]dioxin and modification of its sidechain. As a starting material of the synthesis it was used commercially available 4'-bromo-(2,2':6',2''-terpyridine). The synthetic sub-steps included Suzuki cross- coupling, bromination and C-H bond activation. Then it was also reported the complexation of synthesized oligomer with zinc and iron cations.
Preparation and properties of building blocks of specialty polymers
Šichová, Kristýna
This Diploma Thesis presents results obtained by solution of two partial projects: a) Preparation of monomers from renewable sources using metathesis and tandem hydrogenation catalyzed with ruthenium compounds - project solved during my Erasmus stay at the Université de Rennes 1 in France; b) Preparation and properties of ,-bis(tpy)quarterthiophene oligomers carrying ionic side groups as oligomonomers for polyelectrolyte conjugated dynamers - project solved at the Department of Physical and Macromolecular Chemistry, Faculty of Science, Charles University in Prague. Project a): Self-metathesis of 1,2-epoxyhex-5-ene (but-3-enyloxirane) and its cross-metathesis with methyl acrylate and acrylonitrile catalyzed with ruthenium compounds as well as tandem design of these metatheses and consecutive hydrogenation of their products by gaseous hydrogen have been optimized. The following influences have been studied and tuned: (i) type of the catalyst (Grubbs, Hoveyda, Zhan) and its concentration and method of dosing, (ii) concentration of reactants and additives, (iii) type of solvent, and (iv) reaction temperature. Reactions were monitored by the GC, GC and MS methods and the products were characterized by the NMR method. Methyl 6,7-epoxyheptanoate (methyl 5-oxiranylpentanoate) obtained by the tandem...
Preparation and characterization of bis(terpyridyl)fluorene based polymers
Hrma, Martin
The diploma thesis presents the preparation of ,-bisterpyridinylfluorenes (unimers) containing fluorene unit in the central block either directly attached to terpyridine (tpy) end groups or via 1,4-phenylene or thiophene-2,5-diyl linker. Synthesized unimers were subsequently used for the preparation of metallo-supramolecular polymers with Zn2+ and Fe2+ ions. The prepared unimers were characterized by NMR, IR and HR-MS, their optical properties were investigated using absorption and emission spectroscopy and cyclic voltammetry. Molecular weight distribution for the prepared Fe-polymers was determined by GPC. The number-average degree of polymerization equal to 7 for an equimolar ratio between unimer and Fe2+ in a diluted solution was determined for polymers composed of unimer with thiophene-2,5- diyl linker. By using the viscometric measurements the ongoing constitutional dynamics in solutions of metallo-supramolecular polymers was proven. The overstoichiometric amount of metal ions in solution resulted in equilibrium shortening of the polymer chains together with end-capping of terminal tpy ligands by Mt2+ ions. Unimer with thiophene-2,5-diyl linker exhibited unique properties involving significantly red-shifted absorption and emission maxima, as well as the different behavior during assembling...

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