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Synthesis and structural properties of arsenates of selected organic amines
Večerka, Jakub ; Havlíček, David (advisor) ; Vojtíšek, Pavel (referee)
Five organic-inorganic hybrid crystals composed of various organic amines and arsenic acid were prepared. Their stoichiometry was investigated by elementary analysis and their structures were elucidated by means of X-ray crystallography. The length of hydrogen bonds was determined. Further, the thermogravimetric analysis was performed in order to test the thermal stability of compounds prepared. The obtained data were compared with those gained for phosphoric analogues, which were described in papers published and the dissertation thesis of Mgr. Chudoba. The arsenates and phosphates were compared taking into account their structural differences, the length and the arrangement of the hydrogen bonds.
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Complexes of 2,6-bis[(N-methylpiperazine-1-yl)methyl]-4-formyl phenol
Marečková, Vendula ; Vojtíšek, Pavel (advisor) ; Kubíček, Vojtěch (referee)
Thirteen new dinuclear complexes of ligand 2,6-bis[(N-methylpiperazine-1- yl)methyl]-4-formyl phenol (L1) were prepared. Copper(II) and palladium(II) salts were used for the syntheses. Following compounds were prepared: [Cu2L1(CH3COO)2]ClO4, [Cu2L1(CF3COO)2(ClO4)][Cu2L1(CF3COO)2]ClO4, [Pd2L1(CH3COO)3], [Pd2L1(CF3COO)3], [Pd2L1(Cl)4]. These ones should act as anion receptors. The acetates were exchanged for phenylphosphinates in the case of the complex cation [Cu2L1(CH3COO)2]+ and the structure of [Cu2L1(phPO2H)2]ClO4 was obtained. Geometry of coordination shell of Cu2+ - ions in prepared complexes is tetragonal pyramid. The UV-VIS spectroscopy was used for study of interactions in system of the ligand - metal - anion. Interactions between the ligand and metals in oxidation state 2 were observed as well as interactions between the complex [Cu2L1(CH3COO)2]ClO4 and sodium salts.
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Symmetrical aminophosphinates
Procházková, Soňa ; Kubíček, Vojtěch (advisor) ; Vojtíšek, Pavel (referee)
Title: Symmetrical aminophosphinates Author: Bc. Soňa Procházková Department of Inorganic Chemistry, Faculty of Science, Charles University Supervisor: RNDr. Vojtěch Kubíček, Ph.D. Supervisor's email address: kubicek@natur.cuni.cz ABSTRACT Two types of α-aminophosphinates were prepared and studied: phosphinate analogues of iminodiacetic acid − aminobis(methyl(hydroxymethyl)phosphinic acid) (IDPhm ) and aminobis(methyl(2-carboxyethyl)phosphinic acid) (IDPce ), and bis(aminomethyl- phosphinates) − (hydroxy(fenyl)methylen)bis(aminomethylphosphinic acid) (PheOHABPin) and (methylen)bis(aminomethylphosphinic acid) (ABPin). All prepared compounds were fully characterized (by NMR, MS, elemental analysis). One crystal structure was determined by X-ray singlecrystal analysis. The diphosphinates were synthesized by Mannich type reaction, whereas the bis(aminomethylphosphinates) were prepared by multistep synthesis including reactive silylesters. Compounds were prepared in moderate or good yields Acid-base and coordination properties of ligands were investigated and compared by potentiometric and NMR titrations. The values of protonation constants of aminogroups, which determine stability of complexes, showed surprising results. An extremely low basicity of nitrogen atom was found in diphosphinates. So, these compounds...
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Bifunctional chelators for selective copper(II) binding
Paúrová, Monika ; Kotek, Jan (advisor) ; Vojtíšek, Pavel (referee)
Title: Bifunctional chelators for selective copper(II) binding Autor: Bc. Monika Paúrová Department: Department of Inorganic Chemistry, Faculty of Science Supervisor: doc. RNDr. Jan Kotek, Ph.D. Supervisor's e-mail: modrej@natur.cuni.cz Abstract: In this Master thesis, cyclam bifunctional derivatives bearing pendant phosphinate groups (4-methyl-11-p-aminobenzyl-1,4,8,11-tetraazacyclotetradecane-1,8- bis(methylenephosphinic acid)) and phosphonate groups (4-methyl-11-p-aminobenzyl- 1,4,8,11-tetraazacyclotetradecane-1,8-bis(methylenephosphonic acid)), were prepared and studied as potential ligands for complexation of divalent copper. These ligands are suitable for binding to a macromolecular carrier. Keywords: radiomedicine, copper, cyclam, chelating agent, phosphinate, phosphonate, kinetic inertness, kinetic lability, thermodynamic stability
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Alternative synthesis of of 1-(diphenylphosphino)-1'-(N,N-dimethylaminomethyl)ferrocene
Zábranský, Martin ; Štěpnička, Petr (advisor) ; Vojtíšek, Pavel (referee)
An alternative, more straightforward and effective method for the preparation of 1- (diphenylphosphino)-1'-(N,N-dimethylaminomethyl)ferrocene was developed using 1-bromo- 1'-(diphenylphosphino)ferrocene as the starting material and Eschenmoser's salt as an aminomethylation agent. Purity of thus prepared phosphinoamine was verified by 1 H and 31 P NMR spectroscopy and by comparison of the data with those reported in the literature (M. E. Wright, Organometallics, 1990, 9, 853). The coordination chemistry of this compound was investigated in gold(I) complexes. Thus, chlorido[1-(diphenylphosphino)-1'-(N,N-dimethyl- aminomethyl)ferrocene]gold(I) complex was synthesized and converted to ill-defined [1- (diphenylphosphino)-1'-(N,N-dimethylaminomethyl)ferrocene]gold(I) perchlorate by halogen abstraction with AgClO4. Protonization of the nitrogen atom in both compounds with hydrogen chloride yielded the corresponding hydrochlorides. It was shown that 1- (diphenylphosphino)-1'-(N,N-dimethylaminomethyl)ferrocene is coordinated as a simple phosphine in the resulting complexes while its amine nitrogen is protonated. All these complexes were characterized by means of 1 H, 31 P and 13 C NMR spectroscopy, mass spectroscopy with electrospray ionisation, elemental analysis and by single-crystal X-ray diffraction analysis.
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Education in inorganic chemistry in the context of common life
Matoušková, Šárka ; Čtrnáctová, Hana (advisor) ; Vojtíšek, Pavel (referee) ; Klečková, Marta (referee)
CHARLES UNIVERSITY IN PRAGUE Faculty of Science Department of Teaching& Didactics of Chemistry Ph.D. study program: Chemistry Education Education in Inorganic Chemistry in Context of Common Life Ph. D. thesis Mgr. Šárka Matoušková Abstract The objective of this Ph.D. thesis is to contribute to the effectiveness and quality of education of inorganic chemistry in the context of common life. The first chapter characterizes the current state of inorganic chemistry as a science and as a teaching subject. The requirements of the teachers teaching inorganic chemistry in secondary schools were determined by using the method of personal interview in the second chapter. After comparing the school systems in the third chapter and the analysis of selected textbooks used in the Czech Republic and in one of the countries of Germany, the criteria for creating teaching materials for inorganic chemistry were set. A textbook on the topic of the transition metals for secondary school pupils was created by means of a transformation of a scientific text. Finally, the textbook was evaluated by chemistry teachers at secondary schools in the form of a questionnaire survey and adjusted to the final form. Keywords: school system, secondary school, inorganic chemistry, chemistry education, textbook, transition metals, interview,...
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Complexes of metals as potential anion receptors
Marečková, Vendula ; Vojtíšek, Pavel (advisor) ; Mosinger, Jiří (referee)
An important class of anion receptors are based on bimetallic complexes with phenols bearing an pendant arms in 2,6-positions. A ligand of this type, 2,6-bis[(N- methylpiperazine-1-yl)methyl]-4-formyl phenol (L1), was prepared using the Mannich reaction. An attempt to prepare a similar compound L2 yield only an oily product. The molecular structure of compound L1 was determinated by X-ray diffraction. Comparison of the L1 structure with similar ones from CCDC showed important influence of the intramolecular H-bond on pendant arms orientations in this type of compounds. Further synthetic exploitation of the aldehyde group (in the position 4) was tested by reaction with 4-nitroaniline. The Shiff base (L3) was obtained but only as an oily substance. Reactions of L1 with Cu(ii) and Zn(ii) perchlorate or acetate produce complexes; the compound [Cu2L1(OH)(OAc)(H2O)]ClO4 (K1) was obtained in a crystallic form. The interactions of anion-bimetallic complex receptor were discused from stereochemical point of view using the structural data from CCDC in the last part of this work.
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Exectrochemical methods as tools for study complex macrocyclic moleculs
Liška, Alan ; Vojtíšek, Pavel (advisor) ; Liška, František (referee)
By means of electrochemical techniques, the electroreduction of polynitrocalix[4]arenes - molecules with multiple redox centers - was investigated and described. Based on interpretation of experimental data and on their correlation with quantum chemical calculations the relationship between structure and redox properties of the title molecules was revealed and discussed. It was shown that the tetranitrocalix[4]arenes involve two different couples of equivalent nitrogroups, what confirms experimentally the pinched shape of the molecule even in solution. The sequence of reduction steps was determined and the corresponding mechanism described. In the first part of the thesis different reduction mechanisms of p-substituted nitroaromates were found in dependence on substitution. It points to an important influence of lower ring substitution on the redox properties of the whole tetranitrocalix[4]arene.
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Quantitative analysis by X-Ray powder diffraction
Stachová, Sandra ; Havlíček, David (advisor) ; Vojtíšek, Pavel (referee)
Quantitative analysis methods using X-ray powder diffraction are still highly actual conception in the area of research of modern materials. The Reference Intensity Ratio (RIR) method is used here for quantitative analysis by X-ray powder diffraction of model samples in this bachelor thesis. The model samples are three mixtures of corundum, mullite and calcite. To get diffraction patterns of the mixtures, two different diffractometers are used and their outputs are then compared.
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Synthesis of nanostructured ZnFe2O4 as a sorbent for H2S removal from syngas
Košťálová, Zuzana ; Nižňanský, Daniel (advisor) ; Vojtíšek, Pavel (referee)
The use of sorption properties of materials as sorbents for removing unwanted substances from gasified solid or liquid fuels (coal, oil, natural gas and biomass) in the heating plant industry seems to be more suitable than existing technology. In this diploma work, ZnFe2O4 is studied as a possible sorbent for the removal of H2S from gasified fuel. ZnFe2O4 has been prepared by various methods in the form of nanoparticles and nanocomposites. The prepared samples were characterized by powder X- ray diffraction, electron microscopy, BET measurement and thermal analysis. Further, the sorption activity of the samples was studied with regard to H2S. The results were evaluated with respect to the possible application of the prepared materials in heating plant industry. Keywords: ZnFe2O4, H2S absorption, sol-gel method, sol-gel auto-combustion method, SBA-15.
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