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Novel conjugated polymers of the metallo-supramolecular and polyelectrolyte class
Hladysh, Sviatoslav ; Vohlídal, Jiří (advisor) ; Strachota, Adam (referee) ; Jindřich, Jindřich (referee)
This thesis targets the development of conjugated polymers with improved process ability from solutions. Two types of ionic polymers are addressed: (i) conjugated metallo-supramolecular polymers (MSPs) composed of conjugated heteroaromatic unimers (building blocks) linked to chains by various metal ions giving charged main chains, and (ii) polythiophene polyelectrolytes containing ionic pendants. Processing advantages of conjugated polyelectrolytes consist in the possibility of their processing from solutions in green solvents such as alcohols or even water. The advantages of MSPs consist in the thermodynamic control of the degree of polymerization (length) of their chains in solutions by the choice of solvent and temperature. As a result, MSPs reversibly provide systems of low viscosity that can be processed from solutions more easily than high-molar-mass polymers giving highly viscous solutions. Synthesis of appropriately designed unimer(s) is the key step of preparation of an MSP. Within this thesis, a series of novel unimers composed of linear oligothiophene type (mono-, bi-, ter- a thieno-thiophene- diyl) central blocks capped with 2,6-bis(oxazoline-2-yl)pyridine (pybox) or 2,6-bis(imidazole-2-...
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Spectroscopy study of metal complexes with terpyridyl ligands
Kožíšek, Jan ; Šloufová, Ivana (advisor) ; Procházka, Marek (referee)
The work is focused on preparation and characterization of octahedral Fe(II) complexes of 2,2′:6′,2′′-terpyridine (tpy) substituted in 4' position by various groups: Cl (tpyCl), chlorophenyl (tpyPhCl) and 2-thienyl (Ttpy)). Formation and stability of prepared complexes were studied by UV/vis spectroscopy on the basis of titration of tpy ligands by Fe(II) ions. The molar absorption coefficient of the metal-to-ligand charge transfer (MLCT) band was found to increase in the order: tpy < tpyCl < tpyPhCl < Ttpy. The MLCT band position increases in the same order, starting from 551 nm for [Fe(tpy)2]2+ to 576 nm for [Fe(Ttpy)2]2+ . Raman scattering (RS) spectra of tpy ligands were obtained upon non-resonance 780 nm excitation. Four excitation wavelengths (445, 532, 633 a 780 nm) were used for measurement Fe(II) complexes. The excitation profiles of both Raman scattering and surface-enhanced Raman scattering (SERS) spectra were constructed for [Fe(tpyCl)2]2+ complex. On the basis of DFT calculations performed for this complex, the Raman active modes have been assigned to the symmetry species of the D2d point group. Similarly as for the previously studied [Fe(tpy)2]2+ complex, activation of E modes in the region of MLCT band suggests contribution of Herzberg-Teller mechanism to the overall molecular...
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Novel conjugated polymers of the metallo-supramolecular and polyelectrolyte class
Hladysh, Sviatoslav
This thesis targets the development of conjugated polymers with improved processability from solutions. Two types of ionic polymers are addressed: (i) conjugated metallo-supramolecular polymers (MSPs) composed of conjugated heteroaromatic unimers (building blocks) linked to chains by various metal ions giving charged main chains, and (ii) polythiophene polyelectrolytes containing ionic pendants. Processing advantages of conjugated polyelectrolytes consist in the possibility of their processing from solutions in green solvents such as alcohols or even water. The advantages of MSPs consist in the thermodynamic control of the degree of polymerization (length) of their chains in solutions by the choice of solvent and temperature. As a result, MSPs reversibly provide systems of low viscosity that can be processed from solutions more easily than high-molar- mass polymers giving highly viscous solutions. Synthesis of appropriately designed unimer(s) is the key step of preparation of an MSP. Within this thesis, a series of novel unimers composed of linear oligothiophene type (mono-, bi-, ter- a thieno-thiophene -diyl) central blocks capped with 2,6-bis(2-oxazolinyl)pyridine (pybox) or 2,6-bis(2-imidazolyl)pyridine (bzimpy) end- groups have been successfully prepared, characterized and assembled with...
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Spectroscopy study of metal complexes with terpyridyl ligands
Kožíšek, Jan ; Šloufová, Ivana (advisor) ; Procházka, Marek (referee)
The work is focused on preparation and characterization of octahedral Fe(II) complexes of 2,2′:6′,2′′-terpyridine (tpy) substituted in 4' position by various groups: Cl (tpyCl), chlorophenyl (tpyPhCl) and 2-thienyl (Ttpy)). Formation and stability of prepared complexes were studied by UV/vis spectroscopy on the basis of titration of tpy ligands by Fe(II) ions. The molar absorption coefficient of the metal-to-ligand charge transfer (MLCT) band was found to increase in the order: tpy < tpyCl < tpyPhCl < Ttpy. The MLCT band position increases in the same order, starting from 551 nm for [Fe(tpy)2]2+ to 576 nm for [Fe(Ttpy)2]2+ . Raman scattering (RS) spectra of tpy ligands were obtained upon non-resonance 780 nm excitation. Four excitation wavelengths (445, 532, 633 a 780 nm) were used for measurement Fe(II) complexes. The excitation profiles of both Raman scattering and surface-enhanced Raman scattering (SERS) spectra were constructed for [Fe(tpyCl)2]2+ complex. On the basis of DFT calculations performed for this complex, the Raman active modes have been assigned to the symmetry species of the D2d point group. Similarly as for the previously studied [Fe(tpy)2]2+ complex, activation of E modes in the region of MLCT band suggests contribution of Herzberg-Teller mechanism to the overall molecular...
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Effect of perfluoroalkyl substituents onthe formation and costitutional dynamics of Schiff bases
Štrympl, Ondřej ; Vohlídal, Jiří (advisor) ; Jindřich, Jindřich (referee)
New synthetic routes were designed and applied for novel bisperfluoroalkylated benzene derivatives: 2,5-bis(perfluorooctyl)benzene-1,4-dicarbaldehyde, its dimethylacetal and 2,5- bis(trifluoromethyl)benzene-1,4-diamine. Methods for purification of those derivatives were developed and used to obtain pure crystalline compounds. Crystals of the mentioned diamine and diacetal were obtained in quality suitable for RTG analysis while crystals of dialdehyde were of sufficient quality. New synthesis and purification protocol was designed for 2,5-bis(trifluoromethyl)benzene- 1,4-dialdehyde yielding sufficiently pure product, although isolated amounts are rather small ( yields about 20%) . 2,5-diiodobenzene-1,4-diamine was synthetised. It should be possible to prepare 2,5- bis(perfluorooktyl)benzene-1,4-diamine from this compound either by direct or indirect approach. Nevertheless, the syntheses were yet unsuccessful. A series of eight Schiff bases derived from 3,5-bistrifluoromethylated benzeneamine, benzylamine and benzaldehyde, and three reference bases based on thiophene-2-carbadehyde, benzaldehyde and phenylacetaldehyde was prepared. Kinetics of those species' formation in CDCl3 (all reactions run without catalyst) and THF (necessity of catalysis and susceptibility of equilibria to water) were studied. The...
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Novel conjugated polymers of the metallo-supramolecular and polyelectrolyte class
Hladysh, Sviatoslav
This thesis targets the development of conjugated polymers with improved processability from solutions. Two types of ionic polymers are addressed: (i) conjugated metallo-supramolecular polymers (MSPs) composed of conjugated heteroaromatic unimers (building blocks) linked to chains by various metal ions giving charged main chains, and (ii) polythiophene polyelectrolytes containing ionic pendants. Processing advantages of conjugated polyelectrolytes consist in the possibility of their processing from solutions in green solvents such as alcohols or even water. The advantages of MSPs consist in the thermodynamic control of the degree of polymerization (length) of their chains in solutions by the choice of solvent and temperature. As a result, MSPs reversibly provide systems of low viscosity that can be processed from solutions more easily than high-molar- mass polymers giving highly viscous solutions. Synthesis of appropriately designed unimer(s) is the key step of preparation of an MSP. Within this thesis, a series of novel unimers composed of linear oligothiophene type (mono-, bi-, ter- a thieno-thiophene -diyl) central blocks capped with 2,6-bis(2-oxazolinyl)pyridine (pybox) or 2,6-bis(2-imidazolyl)pyridine (bzimpy) end- groups have been successfully prepared, characterized and assembled with...
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Novel conjugated polymers of the metallo-supramolecular and polyelectrolyte class
Hladysh, Sviatoslav ; Vohlídal, Jiří (advisor) ; Strachota, Adam (referee) ; Jindřich, Jindřich (referee)
This thesis targets the development of conjugated polymers with improved process ability from solutions. Two types of ionic polymers are addressed: (i) conjugated metallo-supramolecular polymers (MSPs) composed of conjugated heteroaromatic unimers (building blocks) linked to chains by various metal ions giving charged main chains, and (ii) polythiophene polyelectrolytes containing ionic pendants. Processing advantages of conjugated polyelectrolytes consist in the possibility of their processing from solutions in green solvents such as alcohols or even water. The advantages of MSPs consist in the thermodynamic control of the degree of polymerization (length) of their chains in solutions by the choice of solvent and temperature. As a result, MSPs reversibly provide systems of low viscosity that can be processed from solutions more easily than high-molar-mass polymers giving highly viscous solutions. Synthesis of appropriately designed unimer(s) is the key step of preparation of an MSP. Within this thesis, a series of novel unimers composed of linear oligothiophene type (mono-, bi-, ter- a thieno-thiophene- diyl) central blocks capped with 2,6-bis(oxazoline-2-yl)pyridine (pybox) or 2,6-bis(imidazole-2-...
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