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Synthesis of Novel Fused N-Heterocyclic [2.2]Paracyclophanes Using C-H Activation/Annulation
Kepková, Klementýna ; Nečas, David (advisor) ; Matoušová, Eliška (referee)
This bachelor thesis is focused on the development of a new methodology leading to a novel type of N-heterocyclic [2,2]Paracyclophanes (we can also view these compounds as isoquinoline derivatives) based on directed C-H activation/annulation process. Within the thesis, necessary [2,2]Paracyclophane derivatives containing appropriate directing group and non-commercial alkynes have been prepared. Suitable catalytic conditions for the C-H activation/annulation reaction sequence have been found and subsequently optimized. Finally, to demonstrate the applicability of that method, several new N-heterocyclic [2,2]Paracyclophane derivatives have been prepared and characterized successfully. Key words: [2.2]Paracyclophane, C-H activation, annulation, Isoquinoline, directing group
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Synthesis of Azafluoranthene Derivatives via C-H Activation/Annulation Process.
Hladík, Ondřej ; Nečas, David (advisor) ; Rýček, Lukáš (referee)
The azafluoranthenes are a small group of natural substances, occuring in tropical vines from Menispermaceae family. They display promising medicinal effects (such as anti-HIV, cytotoxic activity) and other biological activities have been predicted. This bachelor thesis is focused on the synthesis of azafluoranthene core via directed C-H activation/annulation process. Firstly, required starting compounds have been prepared. In the next step, suitable catalytical conditions enabling the crucial transformation have been found and optimized. Finally, the applicability of the developed methodology has been confirmed by the synthesis of several new 1-azafluoranthene derivatives. Keywords: C-H activation, annulation, 1-azafluorathene, rhodium
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Characterization of organogold compounds
Shcherbachenko, Elena ; Roithová, Jana (advisor) ; Míšek, Jiří (referee)
Geminally diaurated complexes are important intermediates involved in some of the gold catalyzed reactions and therefore they have become a subject of the current research. The aim of this thesis was to assess the influence of electronic structure of an aryl ligand on the stability of gold complexes with three-center-two-electron interaction Au2C. A series of geminally diaurated complexes was obtained by a reaction of gold complex [(IPr)Au(NCMe)]BF4 (IPr = 1,3-bis(2,6-di-iso-propylphenyl)imidazol-2-ylidene) with arylboronic acids ArB(OH)2 bearing different substituents at the aryl group (Ar = para- O2NC6H4, para-NCC6H4, para-ClC6H4, C6H5, para-H3CC6H4, para-H3COC6H4, meta- O2NC6H4, meta-NCC6H4, meta-H3CC6H4, ortho-O2NC6H4, ortho-NCC6H4, ortho-H3CC6H4). Mass spectrometry (MS) was used as the main experimental method in this study. Appearance energies (AE) for the fragmentation of geminally diaurated complexes were estimated by the methods MS/MS. The obtained energies were plotted against the corresponding Hammett σ-constants to assess the correlation between the electronic structure of a given aryl ligand and the stability of the Au2C bond. It was found that structures of gold complexes derived from the cyanophenylboronic acids do not correspond to the geminally diaurated complexes but to the...
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New C-H activations and cross-coupling reactions for modification of deazapurine nucleobases
Sabat, Nazarii ; Hocek, Michal (advisor) ; Tobrman, Tomáš (referee) ; Hlaváč, Jan (referee)
This PhD thesis reports the development of novel C-H activation strategies and aqueous-phase Suzuki-Miyaura cross-coupling reactions for the synthesis of modified deazapurine nucleobases. The methodologies of chemo- and regioselective synthesis of highly functionalized deazapurines have been developed by using modern C-H activation chemistry. Various functional groups such as amino-, imido-, silyl- and phosphonyl- were introduced by C-H activation reactions. Amino deazapurine derivatives were synthesized by developed Pd/Cu-catalyzed direct C-H amination and C-H chloroamination of 6-substituted 7-deazapurines with N-chloro-N- alkyl-arylsulfonamides. C-H imidation reactions of pyrrolopirimidines were performed under ferrocene catalysis with N-succinimido- or N-phtalimidoperesters. In order to obtain silylated derivatives, Ir-catalyzed C-H silylations of phenyldeazapurines with alkyl silanes were designed. Highly interesting deazapurine phosphonates were prepared by using Mn-promoted C-H phosphonation method and were further transformed into the corresponding phosphonic acids. All of the developed direct C-H functionalization reactions proceeded regioselectively at position 8 in deazapurine core, except for C-H silylation where reaction undergoes mainly as directed ortho C-H silylation on phenyl ring,...
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Characterization of organogold compounds
Shcherbachenko, Elena ; Roithová, Jana (advisor) ; Míšek, Jiří (referee)
Geminally diaurated complexes are important intermediates involved in some of the gold catalyzed reactions and therefore they have become a subject of the current research. The aim of this thesis was to assess the influence of electronic structure of an aryl ligand on the stability of gold complexes with three-center-two-electron interaction Au2C. A series of geminally diaurated complexes was obtained by a reaction of gold complex [(IPr)Au(NCMe)]BF4 (IPr = 1,3-bis(2,6-di-iso-propylphenyl)imidazol-2-ylidene) with arylboronic acids ArB(OH)2 bearing different substituents at the aryl group (Ar = para- O2NC6H4, para-NCC6H4, para-ClC6H4, C6H5, para-H3CC6H4, para-H3COC6H4, meta- O2NC6H4, meta-NCC6H4, meta-H3CC6H4, ortho-O2NC6H4, ortho-NCC6H4, ortho-H3CC6H4). Mass spectrometry (MS) was used as the main experimental method in this study. Appearance energies (AE) for the fragmentation of geminally diaurated complexes were estimated by the methods MS/MS. The obtained energies were plotted against the corresponding Hammett σ-constants to assess the correlation between the electronic structure of a given aryl ligand and the stability of the Au2C bond. It was found that structures of gold complexes derived from the cyanophenylboronic acids do not correspond to the geminally diaurated complexes but to the...
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New cross-coupling reactions and C-H activations for synthesis of modified nucleobase analogues
Krömer, Matouš ; Hocek, Michal (advisor) ; Kotora, Martin (referee)
6 Abstract A novel methodology of construction of 6,7-disubstituted 7-deazapurines by serial of orthogonal cross-coupling reactions was developed. The Liebeskind-Srogl reaction was optimized and the reactivity of a few boronic acids was explored. Library of 3×3 disubstuted analogues of deazapurines was synthesized utilizing this method. In the second part of this work, the scope of direct alkylation of purine derivatives was verified. Keywords purine, 7-deazapurine, orthogonal cross-coupling reactions, C-H activations
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Přímá C-H arylace purinů a purinových nukleosidů
Čerňa, Igor ; Hocek, Michal
Direct C–H arylation of purines to position 8 by diverse aryl halides was achieved using Pd catalysis in the presence of CuI and Cs2CO3. The methodology was applied in consecutive regioselective synthesis of 2,6,8-trisubstituted purines bearing three different C-substituents in combination with two cross-coupling reaction. In addition, direct arylation of unprotected purine nucleosides with aryl iodides at position 8 was developed to allow straightforward single-step introduction of diverse aryl groups.
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