National Repository of Grey Literature 2 records found  Search took 0.01 seconds. 
Macrocycles and complexation of large metal cations
Faltejsek, Jan ; Hermann, Petr (advisor) ; Drahoš, Bohuslav (referee)
In the last years, radioisotopes of heavy elements from the bottom of the Periodic Table have been increasingly used in nuclear medicine with focus on alpha-therapy. These large metal ions demand ligands fulfilling their special requirements. Complexes of polyazamacrocyclic ligands have been used in radiomedicine for a long time as diagnostic and therapeutic agents. This work aims to con- tribute to understanding of coordination chemistry of large macrocycles toward large metal ions. Thus, this work deals with structural studies, formation and decomplexation kinetics of Ln(III)-H4pyta complexes employing X-ray solid-state and solution NMR/UV-Vis spectroscopic data. The H4pyta is a 18-membered hexaazamacrocycle formed by two pyridine units and four amine groups which are modified with four acetate pendant arms. In the solid state, several isomeric complexes were structu- rally characterized. Large Ln(III) ions form decacoordinated species with two and two acetates on each side of the macrocyclic N6-plane. Small Ln(III) binds the ligand in a nonadentate fashion with one pendant non-coordinated. In the middle of lanthanide series, both isomers were characterized for several Ln(III) ions. Formation of the complexes takes place in a three-step mechanism with fast formation of an out-of-cage intermediate...
Preparation of precursors to ferrocenophane ligands
Škoch, Karel ; Štěpnička, Petr (advisor) ; Veselý, Jan (referee)
Title: Preparation of precursors to ferrocenophane ligands Autor. Karel Škoch Department: Department of Inorganic Chemistry (Faculty of Science, Charles University in Prague) Supervisor: doc. RNDr. Petr Štěpnička, Ph.D. This thesis focuses on a comparison of two alternative literature methods for the preparation [3]ferrocenophan-1-one. One-step Friedel-Crafts acylation of ferrocene with acryloylchloride in presence of aluminium chloride doesn't provide satisfactory yields and the product is contamined with inseparable impurities. For the preparation of a larger amount of pure [3]ferrocenophan-1-one is therefore suggested the original three-step synthesis starting from ferrocenecarbaldehyde. Ferrocenecarbaldehyde is first reacted with malonic acid to give β- ferrocenylacrylic acid, which can be easily reduced with hydrogen to β-ferrocenylpropionic acid. Treatment of β-ferrocenylpropionic acid with trifluoracetic anhydride acid induces heteroannular cyclization, affording [3]ferrocenophan-1-one with good purity and yields (up to 70 % over the three steps). All compounds were characterised by spectroscopic methods (1 H NMR, 13 C NMR and IR).

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