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Synthesis and catalytic properties of phosphinoferrocene guanidine
Bárta, Ondřej ; Štěpnička, Petr (advisor) ; Vojtíšek, Pavel (referee)
Title: Synthesis and catalytic properties of phosphinoferrocene guanidine Author: Ondřej Bárta Institution: Faculty of Science, Charles University in Prague, Department of Inorganic Chemistry Supervisor: prof. RNDr. Petr Štěpnička, Ph.D. Polar phosphine ligands proved to be useful in homogeneous and biphasic catalysis. Most of these phosphines bears anionic functional groups. On the other hand, functionalization of phosphines by cationic substituents is still quite uncommon, although these functional groups possess properties that could improve catalytic performance of the catalyst. In this regard, nitrogenous bases are particularly attractive due to their inherent basicity and the ability to enter into hydrogen bonding interactions. This thesis describes the synthesis of a novel ferrocene-based phosphine functionalized with guanidine moiety, viz. N-[1′-(diphenylphosphino)ferrocenylmethyl]guanidine (3). This compound was obtained by direct guanylation of 1′-(diphenylphosphino)- 1-(aminomethyl)ferrocene (2) (see scheme). Compound 3 was further used to prepare palladium complexes including the unusual zwitterionic complex [PdCl3(3H)]. The molecular structures of the prepared complexes were determined by X-ray diffraction analysis. Catalytic properties of phosphine 3 and complex [PdCl3(3H)] were...
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Rehabilitation Assistant
Štyndl, Martin ; Kratochvíl, Patrik ; Bárta, Ondřej
This work occupies exclusively the method of implementation of the rehabilition aid.The emphasis is placed on finding the optimal solution for automatic rehabilition asistence. Severalpossible solutions and their advantages or disadvantages are discribed here. The problem ofdetecting the patient´s condition and calculating the expected development is also part of this work.
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Ferrocene phosphinoguanidine donors
Bárta, Ondřej ; Štěpnička, Petr (advisor) ; Dostál, Libor (referee) ; Hoskovcová, Irena (referee)
The "Ferrocene phosphinoguanidine donors" project presented in this Thesis targeted on the synthesis, coordination chemistry and catalytic applications of a rather uncommon class of compounds combining phosphine and guanidine functional groups in their molecules. Two series of such compounds based on ferrocene backbone (henceforth fc = ferrocen-1,1΄-diyl) were studied. Firstly, a reliable synthetic route towards polar phosphinoguanidinium chlorides [R2PfcCH2NHC(NH2)2]Cl, where R = iso-propyl, cyclohexyl, phenyl and 2-furyl, was developed and these ligands were tested as supporting ligands in palladium-catalysed Suzuki-Miyaura-type reactions in biphasic aqueous mixtures and in rhodium-catalysed hydroformylation of 1-hexene. Deduced from the results, the hydrophilic guanidinium tag had a beneficial effect on the catalytic activity and, particularly, the electron-rich phosphines from this series could serve as a useful alternative to commonly used ligands for catalytic applications in polar or aqueous reaction media. Phosphinonitriles R2PfcCN obtained as intermediates during the synthesis of the abovementioned ligands were additionally used for the preparation of the dimeric complexes [Au2(µ-R2PfcCN)2][SbF6]2, in which the gold(I) centre was stabilised by nitrile coordination. These complexes proved...
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Synthesis and catalytic properties of phosphinoferrocene guanidine
Bárta, Ondřej ; Štěpnička, Petr (advisor) ; Vojtíšek, Pavel (referee)
Title: Synthesis and catalytic properties of phosphinoferrocene guanidine Author: Ondřej Bárta Institution: Faculty of Science, Charles University in Prague, Department of Inorganic Chemistry Supervisor: prof. RNDr. Petr Štěpnička, Ph.D. Polar phosphine ligands proved to be useful in homogeneous and biphasic catalysis. Most of these phosphines bears anionic functional groups. On the other hand, functionalization of phosphines by cationic substituents is still quite uncommon, although these functional groups possess properties that could improve catalytic performance of the catalyst. In this regard, nitrogenous bases are particularly attractive due to their inherent basicity and the ability to enter into hydrogen bonding interactions. This thesis describes the synthesis of a novel ferrocene-based phosphine functionalized with guanidine moiety, viz. N-[1′-(diphenylphosphino)ferrocenylmethyl]guanidine (3). This compound was obtained by direct guanylation of 1′-(diphenylphosphino)- 1-(aminomethyl)ferrocene (2) (see scheme). Compound 3 was further used to prepare palladium complexes including the unusual zwitterionic complex [PdCl3(3H)]. The molecular structures of the prepared complexes were determined by X-ray diffraction analysis. Catalytic properties of phosphine 3 and complex [PdCl3(3H)] were...
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Synthesis of a ferrocenyl-substituted bicyclic phosphite
Bárta, Ondřej ; Štěpnička, Petr (advisor) ; Kubíček, Vojtěch (referee)
Title: Synthesis of a ferrocenyl-substituted bicyclic phosphite Author: Ondřej Bárta Institution: Faculty of Science, Charles University in Prague, Department of Inorganic Chemistry Supervisor: prof. RNDr. Petr Štěpnička, Ph.D. This thesis describes the synthesis of a novel bicyclic phosphite ester, {N-(2,6,7-trioxa-1-phosphabicyclo[2.2.2]oct-4-yl)carbamoyl}ferrocene (3). This compound was obtained by the reaction of phosphorus trichloride with the appropriate tris(hydroxymethyl)methyl-amide in the presence of triethylamine or pyridine. The reaction conditions were optimized by varying the solvent, reaction temperature and the base to achive the highest possible yield of the product and to enable its easy and effective chromatographic purification. A new compound, 2-ferrocenyl-4,4-bis(chloromethyl)-4,5-dihydro-1,3-oxazol (4), was isolated as the by-product of this reaction. Compound 3 was further used to prepare the carbonyl complex cis-[W(CO)4(3-κP)2] (5). All the newly prepared compounds were characterized by NMR spectroscopy, mass spectrometry, infrared spectroscopy and by elemental analysis, and their molecular structures were determined by X-ray diffraction analysis. Hydrogen bonds are cooperating to form one-dimensional chains in the crystals of phosphite 3 and solvate 4 × ½ H2O or...
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Elections in real socialism as the instrument of subjugation
Bárta, Ondřej ; Mlejnek, Josef (advisor) ; Machart, Filip (referee)
The thesis aims to provide possible interdisciplinar explanatory schema of the fact, which is in literature as a mass conformity of citizens of real-socialistic régime in Czechoslovakia. Even in the 70s and 80s, in a time of ideological emptiness, was achieved that the vast majority of the population participated in the rituals of power, which could have a considerable psychological impact. People were regularly reminded of their humbling and social psychological task is to present concepts able to describe, how could be such a humiliation at one's self-image processed and what effect this may have on general conformity. By the most symbolic ritual, the elections, it is also necessary to examine, in what form were they period presented, because this also has an impact on the degree of tension between own actions and convictions.
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Language and Reality
Bárta, Ondřej ; Kučera, Jan (advisor) ; Kučera, Rudolf (referee)
This thesis tries to explore how ideologies, namely the national socialism, work. It is based on the presumption that the reality as we experience it, is impacted by the language that we use to describe it. Thus, in accord with the philosophy of Eric Voegelin, it claims that to understand a specific society in its authenticity, it is necessary to examine the means of the language that is used to categorize the world. And it is precisely Voegelins expressions, symbolism and order, that are good instruments to explain the fact that even the nacis created such "reality" that was capable to exclude masses of people from the sphere of moral reciprocity, using a language that refers to a certain view of the world.
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An analysis of the determinants of alcohol consumption in selected OECD countries
Bárta, Ondřej ; Chytil, Zdeněk (advisor) ; Babin, Jan (referee)
This bachelor thesis analyzes impact of selected factors on alcohol consumption among 30 OECD countries. I estimate four econometric models based on data from the period 2000 -- 2010. Main determinants of dependent variable are price, GDP per capita, GDP growth, unemployment rate, long-term unemployment rate, number of hours spent working and share of social expenditures on GDP. I also take the financial crisis under consideration. Two stated hypotheses are: 1. Alcohol consumption is positively correlated with GDP per capita, 2. Alcohol consumption is positively correlated with unemployment rate. Hypothesis no. 1 is confirmed. Hypothesis no. 2 is disproved, therefor alcohol consumption is negatively correlated with unemyployment rate. On the contrary alcohol consumption is positively correlated with long-term uneymployment rate. Other significant factors are share of social expenditures on GDP and lagged alcohol consumption.
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Influence of water regime on growth and quality of selected grass species
BÁRTA, Ondřej
This thesis describes the importance and use of permanent grasslands, or more so-called energy grasses used in the energy sector. For our study we examined these three grasses: Ovsík vyvýšený (Arrhenatherum elatius), Sveřep horský (Bromus carharticus) and Bojínek luční (Phleum pratense). Another, the main task was to determine their resistance to drought. The results based on laboratory work, which between them compared the two variants. One was simulated normal emergence of the species and the second emergence stressed by lack of water. Based on these results, we conclude that we can not say that it would be a downright drought-resistant types. For the two studied species of grasses (Bojínek and Ovsík) are obvious differences in resistance to drought. Sveřep horský (variety - Tacit), however, proved to be the most drought-resistant species. While most sprouted out bojínek luční (variety - Sobol).
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