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Development of new syntheses of condensed aromatic compounds
Kaiser, Reinhard Peter
This work is divided into two parts that are focused on the synthesis and assessment of photophysical properties of two structurally related compounds: (i) 9,9'-spirobifluorenes (SBFs) and (ii) dispiroindeno[2,1-c]fluorenes (DS-IFs). (i) In the first part, a five-step synthetic approach to SBFs was developed and as the crucial step was used an intermolecular [2+2+2] cyclotrimerization of symmetrically or unsymmetrically substituted diynols with alkynes catalyzed by Rh-complexes. Catalyst screening showed that Wilkinson's catalyst (RhCl(PPh3)3) had the highest efficiency in yielding 1,2,3,4-substituted fluorenols - the key intermediates. The fluorenols were then converted into SBFs bearing various electron-donating and -withdrawing groups, aromatic substituents, and -extended aromatic hydrocarbon moieties (PAHs). Altogether 19 different SBFs were prepared and their photophysical properties screened. The fluorescent emission maxima em were in the range of 315-389 nm with excellent quantum yields s (up to 1.00). As far as the substituent effect is concerned the presence of electron-withdrawing substituents on the SBF scaffold results in the red-shift of the emission maxima. (ii) In the second part, a similar synthetic strategy was applied for synthesis DS-IFs. In this instance was utilized again the...
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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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Gold-Catalyzed Cyclizations of 1,5-Enynes
Matouš, Petr ; Pour, Milan (advisor) ; Hlaváč, Jan (referee) ; Veselý, Jan (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department Department of Organic and Bioorganic Chemistry Candidate Mgr. Petr Matouš Supervisor prof. RNDr. Milan Pour, Ph.D. Titel of Doctoral Thesis Gold-Catalyzed Cyclizations of 1,5-Enynes This Ph.D. thesis deals with the development of gold(I)-catalyzed cyclizations of propargylamino acrylates (3-aza-1,5-enynes) in the presence of an external nucleophile. A library of tetrahydropyridines with an unusual hemiaminal ether functional group was thus prepared via the cyclization of a series of substituted enynes. The influence of the protective group as well as the substitution on the chemoselectivity of the reaction was demonstrated. The tetrahydropyridines were further utilized as precursors for the preparation of pharmaceutically important nitrogen heterocycles. The reduction of selected compounds furnished substituted piperidines, while Diels-Alder cycloaddition of alkenylated tetrahydropyridines gave rise to isoquinoline derivatives. Additional ortho-fused heterocycles (furopyridine, pyrrolopyridine and chromenopyridine) were prepared by the intramolecular version of the cyclizations of enynes with pending internal nucleophiles.
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Synthesis of the C15-C20 tiacumicin fragment
Havlíček, Vojtěch
In the diploma thesis, a method for preparation of the unsaturated C15-C20 tiacumicin fragment was developed. Tiacumicin is classified as a macrolidone antibiotic. Although three syntheses of tiacumicin have been recently published, this study has aimed to develop a novel pathway for its preparation utilizing catalytic reactions instead of stoichiometric ones. In the second part, an enantioselective allylation of (E)-3-jod-2-methylpropenal has been developed applying catalysis by a series of N,N'-dioxide catalysts. The asymmetric induction achieved in the allylation was up to 99% ee. This procedure allows relatively simple, straightforward and efficient preparation of wide range of natural products. Keywords tiacumicin, asymmetric synthesis, allylation, catalysis, chiral Lewis bases, organocatalysis
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Gold-Catalyzed Cyclizations of 1,5-Enynes
Matouš, Petr ; Pour, Milan (advisor) ; Hlaváč, Jan (referee) ; Veselý, Jan (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department Department of Organic and Bioorganic Chemistry Candidate Mgr. Petr Matouš Supervisor prof. RNDr. Milan Pour, Ph.D. Titel of Doctoral Thesis Gold-Catalyzed Cyclizations of 1,5-Enynes This Ph.D. thesis deals with the development of gold(I)-catalyzed cyclizations of propargylamino acrylates (3-aza-1,5-enynes) in the presence of an external nucleophile. A library of tetrahydropyridines with an unusual hemiaminal ether functional group was thus prepared via the cyclization of a series of substituted enynes. The influence of the protective group as well as the substitution on the chemoselectivity of the reaction was demonstrated. The tetrahydropyridines were further utilized as precursors for the preparation of pharmaceutically important nitrogen heterocycles. The reduction of selected compounds furnished substituted piperidines, while Diels-Alder cycloaddition of alkenylated tetrahydropyridines gave rise to isoquinoline derivatives. Additional ortho-fused heterocycles (furopyridine, pyrrolopyridine and chromenopyridine) were prepared by the intramolecular version of the cyclizations of enynes with pending internal nucleophiles.
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Catalytic annulation reactions of N-heterocycles with alkynes
Hrubý, Samuel ; Kotora, Martin (advisor) ; Matoušová, Eliška (referee)
The aim of the bachelor thesis was to use C-C and C-H bond cleavage for the synthesis of cationic N-heterocycle compounds. Within the thesis was the aim to study various catalytic systems, reactions considering structural variations of reactants along with the effect of structure of reactants on their reactivity. The synthesis consists of rhodium-catalysed C-C bond cleavage in biphenylene followed C-H activation. Key words: C-C bond activation, C-H bond activation, heterocycles, catalysis
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Synthesis of azaindenofluorenes
Zelina, Ondřej ; Kotora, Martin (advisor) ; Rýček, Lukáš (referee)
Azafluorene derivates are naturally occurring compounds that possess multiple types of biological activity with the potential of being used as pharmaceuticals. Azaindenofluorenes are studied as potential candidates to be used as organic light-emitting diodes because of their photophysical properties. In this work, compounds belonging to these groups were synthesized using cyclotrimerization. Keywords: cyclotrimerization, catalysis, azafluorene, azafluorenone, azaindenofluorene, azaindenofluorenone, natural compound, OLED
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Using Heck reaction for aromatic ring formation in the synthesis of polycyclic compounds
Bažíková, Ema ; Matoušová, Eliška (advisor) ; Míšek, Jiří (referee)
This bachelor's thesis focuses on the synthesis of a polycarbocyclic compound with naphthalene core and the following oxidation to the corresponding ortho-naphthoquinone. The naphthalene and naphthoquinone skeleton can be found in many natural products with interesting biological properties. This thesis extends the scope of a method developed by our group for the synthesis of naturally occurring ortho-naphthoquinones. The key step of the synthesis was to form an aromatic ring using the Heck reaction. Keywords: synthesis, polycyclic compounds, naphthalenes, catalysis, Heck reaction
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Synthesis of selaginpulvilins
Beytlerová, Nela ; Kotora, Martin (advisor) ; Hájíček, Josef (referee)
This bachelor thesis is focused on the application of [2+2+2] cyclotrimerization in the total synthesis of natural fluorene derivate, selaginpulvilin D, which was isolated from the plant Selaginella pulvinata. The plant is used in the traditional Chinese medicine for treatment of asthma and traumatic injuries. The study is focused on development of the catalytic cyclotrimerization reaction that is used to prepare the key intermediate. The integral part of the project is a study how various catalysts and catalytic systems, solvents and reaction temperatures affect the course of the reaction. Synthesis of the suitable cyclotrimerization precursor was achieved from benzaldehyde and the formal synthesis of selaginpulvilin D was completed by conversion of cyclotrimerization product to the known intermediate of the selaginpulvilin D synthesis. Key words: [2+2+2] cyclotrimerization, selaginpulvilin D, natural compound, fluorene core
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Using levoglucosenone in the synthesis of naphthoquinone containing compounds
Neumannová, Johana ; Matoušová, Eliška (advisor) ; Baszczyňski, Ondřej (referee)
This bachelor thesis is focused on using levoglucosenone in the synthesis of the naphthoquinone containing compounds. Levoglucosenone is a versatile and easily available substance which can be prepared by pyrolysis of renewable cellulose-containing materials. The synthesis of the target compound begins with the preparation of the substrate for the tandem reaction (propargyl ether) in three steps. The following key steps of the synthesis include palladium-catalyzed tandem cyclization/Suzuki cross coupling and subsequent Heck reaction. Oxidation of the prepared methoxy-substituted naphthalene yields the o-naphthoquinone, which has a similar structure as some naturally occurring substances with naphthoquinone skeleton, e.g. mansonone D and populene C. Key words: Synthesis, naphthalenes, naphthoquinones, levoglucosenone, catalysis, polycyclic compounds
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