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Synthesis and application of new bipyridine ligands
Bednářová, Eva ; Kotora, Martin (advisor) ; Cibulka, Radek (referee) ; Michelet, Véronique (referee)
2,2'-Bipyridines and their appropriate N,N'-dioxides form a significant class of heteroaromatic compounds, which has found application in various fields of chemistry and predominantly in asymmetric catalysis. One of the most powerful methods for their synthesis is cocyclotrimerization of alkynes with nitriles. A new variant of cyclotrimerization reaction - cocyclotrimerization of halodiynes with nitriles, which results in the formation of 2- and 3-halopyridines, has been developed. The reaction was studied on a wide range of substrates providing the pyridine products in good isolated yields. Formation of an unexpected product of halogen exchange reaction was observed during the course of the study and its origin was elucidated by experimental studies. The prepared 2-halopyridines were used as starting materials for syntheses of new chiral 2,2'-bipyridine ligands. The crucial step of their synthesis turned out to be the reductive dimerization of 2-halopyridines to the corresponding 2,2'-bipyridines. Application of the formed bipyridine ligands was then tested in various metal-catalyzed asymmetric reactions, namely Mukaiyama aldol reaction, hydroxymethylation, conjugate addition, C-H activation of indole and desymmetrization of meso-epoxides, in which one of the bipyridine ligands showed...
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Preparation of cyclodextrin derivatives usable for modifications of solid surfaces
Bednářová, Eva ; Jindřich, Jindřich (advisor) ; Veselý, Jan (referee)
This master thesis deals with preparation of cyclodextrin (CD) derivatives that are suitable for bonding on solid surfaces such as dopamine polymer and gold. The nucleophilic attack of 6I -O-p-toluenesulfonyl--CD (6-tosyl-β-CD) by dithiols created derivatives with substituents bound to CD skeleton by one of the sulphur atom while keeping a free terminal sulphanyl group. Despite initial problems caused by oxidation of the thiols to disulfides, CDs were modified by alkyl or oligoethylene glycol spacers prepared in 60 - 88% yields. The same reaction was used for preparation of derivatives of β-CD with amino group at the end of the tether that was linked to CD by nitrogen atom. For these purposes were used corresponding diamines and reactions proceeded smoothly reaching up to 92% isolated yield. Next, also the chemoselectivity of the reaction with an ambident spacer bearing both amino and sulphanyl functional group was studied and by 2D NMR experiments was proved that substituent was bound to CD through sulphur atom. It was demonstrated on the case of preparation of CD derivative with dimethylene linker that was prepared in 84% yield. A complete set of yet other CD-oligoethylene glycol derivatives with spacers linked to CD skeleton through the sulphur atom and terminated by amino group was prepared by...
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Final report about research in Sokolov post mining sites in 2015 based on agreement between ENKI ops and Institute of Soil Biology BC CAS
Frouz, Jan ; Moradi, J. ; Mudrák, Ondřej ; Albrechtová, Jana ; Kučera, J. ; Kukla, J. ; Bednářová, E. ; Vindušková, O. ; Sebag, D. ; Cailleau, G. ; Brus, Jiří
The report brings main results of the research about soil and ecosystem recovery in post mining landscape near Sokolov based on agreement between ENKI ops and Institute of soil biology, BC CAS.
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Comparison of inheritance tax in the Czech Republic and the Great Britain
BEDNÁŘOVÁ, Eliška
Main goal of my bachelor?s degree paper was comparative study of contemporary adjustment of inheritance tax in Great Britain and Czech Republic and herewith connec-ted prepared plans of Treasury for adjustment of the inheritance tax in CR. Firstly in my paper I aimed for classification of inheritance tax to the fiscal system. From this chapter arose that inheritance tax is according to general rules categorized as property taxes. In the next part I quoted authors dealing with meaning of inheritance tax. While studying this topic I concluded that even though inheritance tax contributes with smaller profit to public budget, it represents very important field in tax systems. In this paper is present description of historical and contemporary form of inheri-tance tax in which I tried to compare their present modifications and development. From these acquired information arise certain general characteristics of the modificati-ons. Contemporary form of inheritance tax in the Czech Republic is aimed at liberation of inheritance tax for kinsmen, whilst the inheritance tax in Great Britain is aimed at taxing of citizens with vast possessions. In next chapter I concentrate on newly arising modifications of inheritance tax in Czech Republic. One of the suggestions includes for example determination of unified tariff. Next suggestion that is debated by the Treasury is of categorizing the inheritance tax to corporate taxes which will be followed by termination of the law 357/1992.Sb., whilst liberation of I. and II. Group and unified inheritance tax rate remains.
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