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Organocatalytic cyclization reactions leading to bicyclic compounds
Hofmanová, Markéta ; Veselý, Jan (advisor) ; Jindřich, Jindřich (referee)
This diploma thesis is focused on the preparation of enaniomerically pure bicyclic compounds with sulfur bridge and based on organocatalytic cyclization reaction. Thiazolone- derived heterocycles with nitrogen and sulfur atom and α,β-unsaturated aldehydes were selected as suitable substrates for this reaction. Furthermore, spirocyclization reaction on isatin-derived ketimines was also studied in this work. Acyl chlorides, trichloro-substituted β- oxoesters, and isocyanates were selected as suitable substrates for this type of reaction. Key words Enantioselective synthesis, organocatalysis, cyclization reaction, spirocyclization, thiazol-2- one, ketimine.
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Preparation of benzoylated derivatives of cyclodextrins
Jůza, Radomír ; Jindřich, Jindřich (advisor) ; Míšek, Jiří (referee)
This master thesis deals with the preparation of the cyclodextrin (CD) derivatives that are suitable for complexation of the electron-rich aromatic compounds such as helicenes. The basic skeleton of native CD was perbenzoylated in all positions 2, 3 and 6 in the first place. Then the nucleophilic attack of carboxylates of benzoic acids with electron- withdrawing groups (NO2) or electron-donating group (NH2) to per(6-deoxy-6-iodo)-CD derivatives were used to prepare the perbenzoylated CD derivatives in the postition 6. Binding constant was determined for the prepared benzoylated derivatives of CD and the racemate of the hexahelicene using the NMR titration. Perbenzoylated derivatives of β-CD in all position 2,3 and 6 with one azido group in position 6 were prepared as well. These derivatives could be covalently bonded as chiral selectors in the stationary phase for the HPLC separation of aromatic enantiomers. Keywords: cylodextrins, persubstitution, benzoyl, 4-nitrobenzoyl, 3,5-dinitrobenzoyl, helicenes, NMR titration, binding constants
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Synthesis of supramolecular components with positive charges and study of their binding to plasma treated surfaces
Garbárová, Veronika ; Jindřich, Jindřich (advisor) ; Jelínek, Ivan (referee)
5 Abstract The aim of this work was to synthesize a series of new compounds capable to show supramolecular interactions with cyclodextrins, such as adamantane or ibuprofen, which also contain permanent positive charges. Therefore, they can be bound electrostatically on negatively charged surfaces. Plasma treated surface which contains carboxylate groups and polymer Nafion® 117 with sulfonate groups have been used as such surfaces. The synthesis has started with introduction of the azido group into the molecule and has been followed by copper catalyzed azide/alkyne cycloaddition reaction with a linker containing positive charges and a propargyl group. Optimal conditions of a binding onto the solid surface and a dependence of the bond stability in water solutions on pH and concentration of salts have been evaluated for selected components using UV spectrometry. Key words: synthesis, positively charged compounds, electrostatic binding, plasma treated surfaces
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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)...
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New Carbanion Rearrangement of Sulfur Compounds and Its Application
Řehová, Lucie ; Jahn, Ullrich (advisor) ; Cibulka, Radek (referee) ; Jindřich, Jindřich (referee)
New Carbanion Rearrangement of Sulfur Compounds and Its Application Abstract This thesis reports the investigation of an unusual reversal in the metalation selectivity of alkyl aryl sulfones and sulfoxides and its application. Such compounds undergo initial directed ortho-metalation at −78 řC despite having an acidic α-hydrogen atom and the resulting aryllithiums rearrange subsequently completely to the initially expected α-sulfonyllithiums on warming. The scope and the limitations for this process were identified. Both carbanion types of sulfones were applied in reactions with various electrophiles. α-Lithiated sulfones generated upon the transmetalation process were used in Julia olefinations. A mechanistic study of the course of the transmetalation reaction is presented. The kinetics of the transmetalation were determined. Investigations concerning the concentration dependence, proton transfer equilibria between the different ortho-sulfonyllithium intermediates and crossover experiments provided the evidence that a concerted intermolecular pathway prevails. On this basis a new integrated synthetic approach to naturally occurring iridoids was developed. It is based on a tandem alkoxycarbonylation/oxidative radical cyclization of the olefins synthesized by the Julia reaction after the investigated...
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Synthesis and properties of conjugated metallo-supramolecular polymers
Štenclová, Pavla ; Svoboda, Jan (advisor) ; Jindřich, Jindřich (referee) ; Strachota, Adam (referee)
More than twenty new bis(tpy)oligothiophenes (tpy stands for 2,2':6',2''-terpyridin-4'-yl) with unsubstituted as well as substituted (with methyl, hexyl, bromohexyl or 6-(4- methoxyphenoxy)hexyl groups) central blocks comprising one to four thiophene rings have been prepared as building blocks (unimers) for constitutional dynamic metallo- supramolecular polymers (MSPs) soluble in common organic solvents. In addition a series of ionic unimers soluble in alcohols and partially in water have been prepared by modification of bromohexyl unimers with trimethylamine or triethylphosphine. Spectroscopic studies have shown that the steric hindrances prevail over the electronic effects of substituents as regards the impact on the delocalization of electrons along unimer chains. Unimers with high steric hindrances in the middle of the central oligothiophene block were found to behave nearly like the unimers with half central block. Three stages of the assembly of MSPs from unimers and metal ions in solutions were characterized by the exclusion chromatography: (i) formation of dimers U-Mt2+ -U in the early stages of assembling, (ii) assembly to longer MSPs chains, and (iii) end-capping with surplus metal ions and partial decomposition of MSPs chains. The observed changes in optical absorption spectra indicate a...
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Modified nucleosides derived from pyrimido[4,5-b]indole
Konč, Juraj ; Hocek, Michal (advisor) ; Jindřich, Jindřich (referee)
Syntheses of two series of 2'-sugar-modified pyrimido[4,5-b]indole nucleosides were developed. The synthetic strategy was based on functional group transformations of the 2'-hydroxy group of the 3',5'-protected ribonucleoside. The key intermediate was prepared via stereoselective nucleobase anion glycosylation of the known 4,6-dichloropyrimido[4,5-b]indole nucleobase with 2,3-O-isopropylidene- 5-O-TBS-protected halogenose, subsequent deprotection under acidic conditions and protection of 3'- and 5'-hydroxy groups with Markiewicz reagent. Pyrimidoindole arabinonucleoside was then synthesized using a sequence of oxidation-reduction reactions of the 2'-hydroxy stereocenter. The synthesis of pyrimidoindole 2'-deoxy- 2'-fluororibonucleoside was achieved by stereoselective SN2 fluorination of the THP-protected arabinoside followed by acidic deprotection. For the biological activity testing, two series of 4-substituted arabinonucleosides and 2'-deoxy- 2'-fluororibonucleosides were synthesized employing nucleophilic substitution or Pd-catalyzed cross-coupling reactions.
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