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Development of New Syntheses of Azaaromatic Compounds with Extended π-System
Ulč, Jan ; Kotora, Martin (advisor) ; Hrdina, Radim (referee) ; Tobrman, Tomáš (referee)
Azapolyaromatic compound are a class of heterocyclic compounds, which contains at least one nitrogen atom. A subclass of these compounds are quinolizinium salts, which contains nitrogen atom in bridgehead position. These salts usually have interesting photophysical properties. Naphthoquinolizinium salts are a group of quinolizinium salts, but their synthesis as well as their photophysical properties haven't been studied in detail yet. This work is about development of a new modular method for preparation of naphthoquinoliziniu salts. This method is based on catalytic C-C and C-H bond activations by transition metal catalysts. 1-Azabiphenylene was used as a starting material, which reacted in catalytic C-C bond cleavage followed by insertion of various alkyne to form benzo[h]quinolines. These benzo[h]quinolines then reacted in catalytic C-H bond activation reaction followed by insertion of another alkyne to form final tetrasubstituted naphthoquinolizinium salts. Photophysical properties of the prepared salts was studied. The developed method was used on a more complex starting material such as linear 1- 1-aza-[3]triphenylene, which was converted to phenanthroquinolines and eventually to the corresponding azonia salts. Key words: azapolyaromatic compounds, catalysis by transition metal complexes, C-C...
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Redox Properties of Conjugated Phosphole Derivatives – Electrochemical Study
Koláčná, Lucie ; Polák, P. ; Tobrman, T. ; Ludvík, Jiří
The study describes pentasubstituted phospholes with a π-conjugated arms in positions 2 and 5 of the phosphole ring. According to the expectations, substituents with electron-donating groups led to lower oxidation potentials, the presence of electron-withdrawing groups shifts the reduction potential to less negative values. Because all studied phospholes have multiple substituents of both types, their resulting potentials represent the sum of their influences. Moreover, since many of the studied compounds have two redox centers (phosphole moiety itself and the pi-conjugated arm), their locations were determined and intramolecular interactions were followed, because substituents which can be conjugated with the π-system of phosphole are able to extend the delocalized π-system resulting in stabilization of primary redox intermediates. Chemical modification of phospholes using various combinations of substituents can set the desired electrochemical properties of studied molecules.
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The synthesis of π-electron systems suitable for transfer and retention of charges
Nejedlý, Jindřich ; Starý, Ivo (advisor) ; Tobrman, Tomáš (referee) ; Storch, Jan (referee)
The aim of my Thesis was to develop a general synthetic methodology for the preparation of long helicenes equipped with suitable functional groups that control their solubility or serve as anchoring groups for attachment to metallic surfaces, especially gold. The well-established transition metal catalyzed [2+2+2] cyclotrimerization of triynes was selected as the key scaffold-forming transformation in the synthesis of long helicenes because of its high regioselectivity, atom efficiency, functional group tolerance and general robustness. A modular approach was used for the preparation of the starting oligoynes, thus enabling a high level of their structural diversity. Individual resorcinol- based aromatic building blocks were interconnected by Sonogashira cross-coupling reactions, providing complex cyclization precursors encompassing up to twelve alkyne units pre-arranged for the multiple [2+2+2] cycloisomerization to produce three six- membered rings from each set of three neighboring alkyne units. Thus, a small series of long helicenes with up to 19 rings constituting the helical scaffold was synthesized. The quadruple cyclization leading to the longest oxahelicene prepared to date was performed in a high-temperature-high-pressure flow reactor at 250 řC in the presence of CpCo(CO)2. The set of...
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Department of Organic and Bioorganic Chemistry
Brůža, Zbyněk ; Pour, Milan (advisor) ; Tobrman, Tomáš (referee) ; Starý, Ivo (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department Department of Organic and Bioorganic Chemistry Candidate Mgr. Zbyněk Brůža Supervisor prof. RNDr. Milan Pour, Ph.D. Title of Doctoral Thesis Synthesis and application of polysubstituted pyranones This Thesis deals with the development of the isomerization of 5-alkyliden-5,6-dihydro-2H- pyran-2-ones to 6-alkyl-5-methylidene-5,6-dihydro-2H-pyran-2-ones. This process is an unusual version of the intramolecular Tsuji-Trost reaction, the products of which are seemingly thermodynamically unfavourable. The methodology developed through the optimization of the reaction conditions tolerated a broad range of functional groups. Quantum chemistry calculations identified the formation of the pyramidal η2-complex as the key step of the reaction, which made the formation of the final products possible.
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The Combination of Organometallic, Transition-Metal Catalyzed, Radical and Carbocationic Reaction Steps to Domino Processes
Jagtap, Pratap Ramling ; Jahn, Ullrich (advisor) ; Tobrman, Tomáš (referee) ; Bureš, Filip (referee)
This work deals with the development of methodology, which couples reactive intermediates of varying oxidation states, in tandem sequences comprising 1,2-organometallic addition/transition metal catalyzed isomerization/Michael addition/SET oxidation/radical cyclization/oxygenation steps in the synthesis of highly functionalized carbocycles. Implementation of this sequence being catalytic in the SET oxidant was studied. 1,4-Diketones were synthesized in a tandem 1,2-addition/ruthenium-catalyzed redox isomerization/enolates oxidation/radical dimerization reaction and results were compared with 1,4-diketones formation via oxidative coupling of ketone enolates. The total synthesis of selective tetrahydrofuran lignans from 1,4-diketones obtained in a tandem addition/isomerization/dimerization reaction is also documented
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Synthesis of aromatic compounds possessing the fluorene unit
Caivano, Ilaria ; Kotora, Martin (advisor) ; Starý, Ivo (referee) ; Tobrman, Tomáš (referee)
Thermal cyclotrimerization was first discovered in 1866 by Bertholet, then, in 1948, Reppe and Schweckendiek reported the first transition metal catalyzed [2+2+2] cyclotrimerization of alkynes using Ni complexes. In the following 70 years of research, transition metal catalyzed [2+2+2] cyclotrimerization have become a powerful method for the synthesis of variously decorated aromatic rings and new catalytic systems as well as reaction conditions have been successfully applied. Herein, I would like to show the use of this reaction for the synthesis of the important class of fluorene-based compounds. In particular, a regioselective cyclotrimerization of 2,4-disubstituted fluorenols was achieved by Ru-catalyzed partially intermolecular [2+2+2] cyclotrimerization of diynes with terminal alkynes. Rh-based complex proved to be a straightforward transition metal catalyst for the construction of selectively fluorinated [5] and [6]helical dispiroindenofluorenes using intramolecular [2+2+2] cycloaddition of triynediols as the key synthetic step. Moreover, Ni complexes demonstrated to be a valid choice for the selective synthesis of unsymmetrical [7]helical indenofluorenones, while other catalytic systems based on Rh, Ru, Pd and Co gave mixture of the desired cyclotrimerization compound together with the...
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The synthesis of π-electron systems suitable for transfer and retention of charges
Nejedlý, Jindřich ; Starý, Ivo (advisor) ; Tobrman, Tomáš (referee) ; Storch, Jan (referee)
The aim of my Thesis was to develop a general synthetic methodology for the preparation of long helicenes equipped with suitable functional groups that control their solubility or serve as anchoring groups for attachment to metallic surfaces, especially gold. The well-established transition metal catalyzed [2+2+2] cyclotrimerization of triynes was selected as the key scaffold-forming transformation in the synthesis of long helicenes because of its high regioselectivity, atom efficiency, functional group tolerance and general robustness. A modular approach was used for the preparation of the starting oligoynes, thus enabling a high level of their structural diversity. Individual resorcinol- based aromatic building blocks were interconnected by Sonogashira cross-coupling reactions, providing complex cyclization precursors encompassing up to twelve alkyne units pre-arranged for the multiple [2+2+2] cycloisomerization to produce three six- membered rings from each set of three neighboring alkyne units. Thus, a small series of long helicenes with up to 19 rings constituting the helical scaffold was synthesized. The quadruple cyclization leading to the longest oxahelicene prepared to date was performed in a high-temperature-high-pressure flow reactor at 250 řC in the presence of CpCo(CO)2. The set of...
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Department of Organic and Bioorganic Chemistry
Brůža, Zbyněk ; Pour, Milan (advisor) ; Tobrman, Tomáš (referee) ; Starý, Ivo (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department Department of Organic and Bioorganic Chemistry Candidate Mgr. Zbyněk Brůža Supervisor prof. RNDr. Milan Pour, Ph.D. Title of Doctoral Thesis Synthesis and application of polysubstituted pyranones This Thesis deals with the development of the isomerization of 5-alkyliden-5,6-dihydro-2H- pyran-2-ones to 6-alkyl-5-methylidene-5,6-dihydro-2H-pyran-2-ones. This process is an unusual version of the intramolecular Tsuji-Trost reaction, the products of which are seemingly thermodynamically unfavourable. The methodology developed through the optimization of the reaction conditions tolerated a broad range of functional groups. Quantum chemistry calculations identified the formation of the pyramidal η2-complex as the key step of the reaction, which made the formation of the final products possible.
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Department of Organic and Bioorganic Chemistry
Brůža, Zbyněk ; Pour, Milan (advisor) ; Tobrman, Tomáš (referee) ; Starý, Ivo (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department Department of Organic and Bioorganic Chemistry Candidate Mgr. Zbyněk Brůža Supervisor prof. RNDr. Milan Pour, Ph.D. Title of Doctoral Thesis Synthesis and application of polysubstituted pyranones This Thesis deals with the development of the isomerization of 5-alkyliden-5,6-dihydro-2H- pyran-2-ones to 6-alkyl-5-methylidene-5,6-dihydro-2H-pyran-2-ones. This process is an unusual version of the intramolecular Tsuji-Trost reaction, the products of which are seemingly thermodynamically unfavourable. The methodology developed through the optimization of the reaction conditions tolerated a broad range of functional groups. Quantum chemistry calculations identified the formation of the pyramidal η2-complex as the key step of the reaction, which made the formation of the final products possible.
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