|
| |
|
| |
|
|
Selective complexation of transition metals ions
Beliš, Marek ; Kotek, Jan (advisor) ; Vojtíšek, Pavel (referee)
Copper radionuclides possess physical properties suitable for utilization in nuclear medicine. Important part of their preparation is separation from mother elements, usually zinc or nickel. Currently used methods of separation have their limits, what opens field for finding new ways. One part of the Thesis contains preparation of simple ion exchangers and their selectivity study. The other part of the Thesis is dedicated to optimization of synthetic steps leading to new bifunctional ligands in suitable form for binding to macromolecular carriers and preparation of new set of exchangers.
|
|
|
Reactivity and properties of triphosphate analogues
Šrein, Jakub ; Kubíček, Vojtěch (advisor) ; Vojtíšek, Pavel (referee)
Reactions leading to cyclization on methylene bridges in PCPCP structure motif were investigated. It was found, that these reactions result in number of various isomers. Some of these isomers were characterized by NMR and MS spectroscopy, but none was isolated. Further, acid-base properties of bis(methylenephosphonato)phosphineic acid were investigated. Formation of complexes was studied with lithium(I), calcium(II), copper(II) and zinc(II) cations. Furthermore, interaction between bis(methylenephosphonato)phosphinic acid and ethylenediamine was investigated by NMR and potentiometric titration. The results show formation of H-bond-based adducts.
|
|
|
Phosphonate and phosphinate derivatives of dipicolylamine
Hlinová, Veronika ; Kubíček, Vojtěch (advisor) ; Vojtíšek, Pavel (referee)
The Diploma Thesis deals with preparation of one phoshonate and two phospinate derivatives of dipicolylamine. Dissociation constants of prepared ligands were determined by potentiometric and NMR titration. Coordination properties of the compounds were studied by combination of potentiometry and UV-VIS spectrophotometry. Stability constants of complexes with selected transition metal ions (Cu2+ , Ni2+ a Zn2+ ) and alkali-earth metals ions (Ca2+ , Mg2+ ) were calculated. Acid-base and coordination properties in the solid state were studied by X-ray diffraction on single-crystals.
|
|
|
Contrast agents for 19F MRI
Koucký, Filip ; Kotek, Jan (advisor) ; Vojtíšek, Pavel (referee)
For 19 F MRI the fluorinated contrast agents should be endowed by short relaxation times. Paramagnetic metal ions make relaxation times shorter and this effect depends on the distance between the metal ion and 19 F nuclei. The aim of this thesis is the synthesis of suitable ligand containing fluorine atoms, and a preparation of its Ni2+ and Cu2+ complexes. Macrocyclic 1,4,8,11- tetraazacyclotetradecane (cyclam) was selected as a starting material as it has optimal ring-size for complexation of the selected ions. The parent macrocycle was substituted by fluorine-containing coordinating pendant arms. Key words: Cyclam; Contrast agents; Phosphonic acids, 19 F MRI, Paramagnetic relaxation, d-metals
|
|
|
Ligand systems for zirconium complexation
Hacaperková, Eliška ; Kubíček, Vojtěch (advisor) ; Vojtíšek, Pavel (referee)
The aim of this thesis is to synthesize new kind of macrocyclic ligands for complexation of Zr4+ . Zirconium(IV) complexes have potential as contrast agents in immuno-PET. Three macrocyclic ligands L1, L2 and L3 with dif- ferent pendant arms (HOPO, maltol, hydroxamate) were designed. Despite numerous attempts syntheses of L1 and L2 were unsuccessful. Ligand L3 was synthesized and the protonation constants were determined by poten- tiometric titration. Complexes [Zr4+ (L3)] were studied too. Catechol ligand L4 was prepared and complexes with cations Zn2+ , Ga3+ and Zr4+ were investigated. 1
|
|
|
Synthesis and catalytic properties of phosphinoferrocene guanidine
Bárta, Ondřej ; Štěpnička, Petr (advisor) ; Vojtíšek, Pavel (referee)
Title: Synthesis and catalytic properties of phosphinoferrocene guanidine Author: Ondřej Bárta Institution: Faculty of Science, Charles University in Prague, Department of Inorganic Chemistry Supervisor: prof. RNDr. Petr Štěpnička, Ph.D. Polar phosphine ligands proved to be useful in homogeneous and biphasic catalysis. Most of these phosphines bears anionic functional groups. On the other hand, functionalization of phosphines by cationic substituents is still quite uncommon, although these functional groups possess properties that could improve catalytic performance of the catalyst. In this regard, nitrogenous bases are particularly attractive due to their inherent basicity and the ability to enter into hydrogen bonding interactions. This thesis describes the synthesis of a novel ferrocene-based phosphine functionalized with guanidine moiety, viz. N-[1′-(diphenylphosphino)ferrocenylmethyl]guanidine (3). This compound was obtained by direct guanylation of 1′-(diphenylphosphino)- 1-(aminomethyl)ferrocene (2) (see scheme). Compound 3 was further used to prepare palladium complexes including the unusual zwitterionic complex [PdCl3(3H)]. The molecular structures of the prepared complexes were determined by X-ray diffraction analysis. Catalytic properties of phosphine 3 and complex [PdCl3(3H)] were...
|
|
|
Contrast agents for 19F magnetic resonance imaging
Martinisková, Marie ; Kotek, Jan (advisor) ; Vojtíšek, Pavel (referee)
The aim of this Master Thesis is to synthesize and study new macrocyclic ligands containing fluorine atoms for use as potencial contrast agents in 19 F magnetic resonance imaging. New ligands were designed as analogues of ligands used in contrast agents already utilized in clinical practice - macrocyclic ligand for complexation of trivalent lanthanide ions based on DOTA skeleton and series of macrocyclic ligands for complexation of divalent nickel ion based on cyclam skeleton. All designed ligands were synthesized a characterized. The complexes [LnIII (dotptfe )]− were tested in vitro and in vivo to study 19 F NMR relaxation times enhancements.
|
|
|
Preparation of titanium and zirconium metallocene complexes with pendant nitrile groups
Večeřa, Miloš ; Štěpnička, Petr (advisor) ; Vojtíšek, Pavel (referee)
Preparation of metallocene complexes of titanium and zirconium with pendant nitrile groups Miloš Večeřa bachelor thesis Abstract: Two cyclopentadienide salts with pendant nitrile groups were prepared in the form of their corresponding lithium salts and these salts were utilized for the preparation of titanium and zirconium metallocene complexes. One of the ligands was already described in the literature, while the other as well as all the prepared group 4 metallocene complexes are new compounds. Starting materials for these syntheses were 6,6-dimethylfulvene and spiro[2.4]hepta-4,6-diene which, upon a nucleophilic attack by 2-lithio-2-methylpropanenitrile, afforded the corresponding substituted lithium cyclopentadienides, which were characterized by 1 H and 13 C NMR spectroscopy and infrared spectroscopy. Then lithium salts were reacted with Cp*TiCl3 and Cp*ZrCl3 to give the corresponding metallocene dichlorides. Solid-state structures of the prepared titanocene dichlorides were elucidated by means of single crystal X-ray diffraction analysis. The obtained structures allowed a comparison with the known structures of the previously prepared homologous derivative. Unfortunately the corresponding zirconocene dichlorides did not crystallize. Moreover, all the newly prepared metallocenes were characterized by 1...
|
guest ::
RSS feed.