National Repository of Grey Literature 248 records found  beginprevious21 - 30nextend  jump to record: Search took 0.01 seconds. 
Preparation of asymmetrically substituted diphenylacetylenes usable in molecular electronics
Rejšek, Jan ; Jindřich, Jindřich (advisor) ; Veselý, Jan (referee)
Preparation of asymetrically substituted diphenylacetylenes usable in molecular electronics Abstract This bachelor's work deals with synthesis of assymetrically substituted diphenylacetylenes and their transformation into (η4 -cyclobutadiene)-(η5 - cyclopentadienyl)cobalt complexes, which should be used and researched as molecular rotors. Multistep synthesis concerning conversion of primary arylamines into tertiary by N-permethylation, nucleophilic acyl substitution and Sonogashira coupling was prepared asymmetrically substituted diphenylacetylene with, which consequently underwent cycloaddition [2 + 2] with cyclopentadienyldicarbonylcobalt. Creating (η4 -cyclobutadiene)-(η5 -cyclopentadienyl)cobalt complexe was identified by MS. Keywords: diphenylacetylene, Sonogashira coupling, (η4 -cyclobutadiene)- (η5 -cyclopentadienyl)cobalt complex, cycloaddition [2 + 2], molecular rotor
Preparation of organocatalysts derived from thiourea containing saccharide units
Řehůřková, Tereza ; Veselý, Jan (advisor) ; Smrček, Stanislav (referee)
4 ABSTRACT This diploma thesis is focused on the synthesis of new bifunctional thiourea organic catalysts containing a carbohydrate moiety, in particular D-glucose with modification on the primary hydroxyl group. The first part of this diploma thesis describes a modification of synthesis of the known bifunctional thiourea catalyst with 2,3,4,6-tetra-O-acetyl-β-D-glucopyranose and (1R,2R)-diaminocyclohexane. The second part is dedicated to the synthesis of new bifunctional thiourea catalysts with modification of the carbohydrate moiety. We focused on per-O-acetyl-β-D-glucopyranose derivatives with pefluoroalkyl moiety on the primary hydroxyl group. We examined different ways of the preparation of 6-O-perfluoroalkylated glucose derivatives. These perfluoroalkylated carbohydrate compounds were transformed into corresponding glycosyl isothiocyanates. Those derivatives upon treatment of (1R,2R)-diaminocyklohexane or 3,5- bis(trifluormethyl)aniline afforded new bifunctional thiourea organocatalysts.
Preparation of enantiomerically pure lactams based on the organocatalysis
Humpl, Marek ; Veselý, Jan (advisor) ; Jindřich, Jindřich (referee)
Different catalytic approaches have been applied to new -lactams preparations. olefin metathesis has been successfully performed with 3--methylidene--lactams. It was verified that 3--methylidene--lactams olefin metathesis is applicable to preparation of biologically active -lactam of Ezetimibe-type.
Organocatalytic asymmetric synthesis of various organic compounds from α,β-unsaturated aledyhes
Kamlar, Martin ; Veselý, Jan (advisor) ; Trnka, Tomáš (referee)
With regard to a fast development in the field of fluoroorganic chemisty, the intention of this diploma thesis is focused to utilize of organocatalysis by secondary amines as catalysts for preparation enantiomerically pure compounds containing fluorine atom in its structure. The preparation of these subsances is realized by way of nucleofilic addition to α,β- unsaturated aldehydes using suitable fluorine containing nuclephilic agent 1-(fluoronitromethylsulphonyl)benzene, to get appropriate 1,4-adduct.
Preparation of alfa(1-4)-linked disaccharides containing D-glukosamine units
Škríba, Anton ; Veselý, Jan (advisor) ; Jindřich, Jindřich (referee)
Abstract The aim of this diploma thesis is a preparation of disaccharide composed from two glucosamine units with 1,2-cis-(1→4)-O-glycosidic bond with the attached linker on reducing end, containing an azide functional group. The first part is focused on synthesis of glycosyl acceptor and glycosyl donor, derived from D-glucosamine, suitable for the construction of 1,2-cis-(1→4)-O-glycosidic linkage. The second part of this work describes the optimization of the glycosylation reaction conditions and also subsequent transformation of disaccharide GlcNAc-α-(1→4)-GlcNAc skeleton.
Aminocarbonydrates as part of cyclic polyamines
Vacková, Zuzana ; Lorenc, Miroslav (advisor) ; Veselý, Jan (referee)
Magnetic resonance imaging is one of the imaging methods that are needed in medicine for diagnostic purposes. This method neither exposes the patient to X-rays, nor any other negative effects on the human organism are known by then. Another significant advantage of MRI is its ability to achieve high contrast even between structurally very similar tissues. The contrast agents commonly used with the magnetic resonance imaging help heighten this ability. Part of these contrast agents is a metal ion, the ion gadolinium (GdIII) is the most commonly used nowadays. But it must be complexed by a suitable ligand. This work deals with the synthesis of a number of potentially suitable model ligands. The saccharide component is even a part of these ligands. This component should enable to achieve a greater solubility of the complex or the possibility of linking other additional saccharide units, another ligand or a detecting group. Several theoretical paths leading to the final fabric were created. Not all of them led to the target, only one was successful. The produced macrocycle is the potentially applicable ligand for complexation with GdIII or other metal ion, it means a good part of the new potential contrast agent.
Preparation of H-bonding organocatalysts
Franc, Michael ; Veselý, Jan (advisor) ; Jindřich, Jindřich (referee)
This bachelor thesis deals with the preparation of chiral (thio)urea and squaramide derivatives, that can act as H-bonding organocatalysts. The catalytic efficiency of the prepared organocatalysts was explored in asymmetric Morita-Baylis-Hillman and aza-Henry reaction.
The Central Bank, its position and activities
Veselý, Jan ; Kotáb, Petr (advisor) ; Kohajda, Michael (referee)
The main objective of this thesis is to describe the functioning of the central bank, the historical development of the Czech National Bank, its organizational structure and internal decision-making mechanisms, activities carried out, its purpose, function and objectives and to incorporate it in the legal system of the Czech Republic. This thesis addresses the involvement of the Czech National Bank for the European System of Central Banks, the functioning of the European Central Bank and the aforementioned European System of Central Banks. Part of the work is devoted to the process of adopting the euro and the relation between Czech Republic this currency. The thesis gives a comprehensive view of the functioning of the Czech National Bank. Thesis is divided into several chapters, and each chapter neatly summarized some part of the whole and to ensure easy orientation at work. The work is drawn from literature, case law and legislation. The work includes the connection of the scientific literature and the author's views. There is a widely used quotes personalities and capabilities in their field and provisions of the legislation, so that the work was valuable informative.
Application of organocatalytic approach for the synthesis of piperidine-2-ones, useful building blocks for the preparation of antidepresants
Humpl, Marek ; Veselý, Jan (advisor) ; Jindřich, Jindřich (referee)
This bachelor thesis is focused on the application of organocatalytic approach for the synthesis of enantiomerically pure substitued piperidine-2-ones from synthetically easily avaiable starting materials and commercially avaiable secondary amine. Substitued piperidine-2-ones are prepared in good yields (49-99 %) and excellent enantioselectivities (93-96 % ee). The key-intermediate in synthesis of (+)-femoxetine is prepared and the synthesis is formally finalised in the overall yield 23 % and enantiomeric excess of 95 %.

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