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Lanthanide macrocyclic complexes with phosphonate/phosphinate pendant arms
Procházková, Soňa
Imaging methods have become an integral part of diagnostic and therapeutic procedures in current medicine. Contrast agents based on metal complexes are often used to improve the final image. Complexes contain radioisotopes in nuclear medicine and gadolinium(III) ion in MRI. These complexes have to show high kinetic and thermodynamic stability and their preparation must not be time consuming. H4DOTA and its derivatives are convenient type of ligand for the formation of stable complexes. This work has focused on phosphonate and phosphinate derivatives of the ligand H4DOTA. The studied compounds can be divided into ligands containing only methylphosphinate/phosphonate (H4DO3APH, H5DO3APOH) and ligands with a second coordination center (H6DO3APIDA, H5DO3APPIN, H4DO3APAM, H8DO3APBP a H7DOTAMBP). The work has examined the possibilities of influencing the way and rate of complexation under different conditions. In order to approach the preparation conditions of radio complexes, kinetics measurements were performed not only under the metal ions excess, but also under the ligand excess. The aim was to compare the results of both types of measurements, which often showed to be different. A mechanism for the formation of various types of intermediates formed during complexation has been proposed. The...
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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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Lanthanide macrocyclic complexes with phosphonate/phosphinate pendant arms
Procházková, Soňa ; Kubíček, Vojtěch (advisor) ; Cígler, Petr (referee) ; Řezanka, Pavel (referee)
Imaging methods have become an integral part of diagnostic and therapeutic procedures in current medicine. Contrast agents based on metal complexes are often used to improve the final image. Complexes contain radioisotopes in nuclear medicine and gadolinium(III) ion in MRI. These complexes have to show high kinetic and thermodynamic stability and their preparation must not be time consuming. H4DOTA and its derivatives are convenient type of ligand for the formation of stable complexes. This work has focused on phosphonate and phosphinate derivatives of the ligand H4DOTA. The studied compounds can be divided into ligands containing only methylphosphinate/phosphonate (H4DO3APH, H5DO3APOH) and ligands with a second coordination center (H6DO3APIDA, H5DO3APPIN, H4DO3APAM, H8DO3APBP a H7DOTAMBP). The work has examined the possibilities of influencing the way and rate of complexation under different conditions. In order to approach the preparation conditions of radio complexes, kinetics measurements were performed not only under the metal ions excess, but also under the ligand excess. The aim was to compare the results of both types of measurements, which often showed to be different. A mechanism for the formation of various types of intermediates formed during complexation has been proposed. The...
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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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Synthesis of alkylphosphinic acids
Procházková, Soňa ; Vojtíšek, Pavel (referee) ; Kubíček, Vojtěch (advisor)
The preparation of methylphosphinic acid and (3-terc-butoxy-3-oxopropyl)phosphinic acid using reaction between bis(trimethylsilyloxy)phosphine (BTSP) and iodomethane or tert-butyl acrylate was investigated. BTSP was generated in situ from ammonium phosphinate and hexamethyldisilazane. Simultaneously, the preparation of BTSP using N,O-bis(trimethylsilyl)acetamide was optimilized. The effect of conditions of the alkylation and addition reactions on the yield of monosubstituted and disubstituted phosphinic acids was examined. Furthemore, the preparation and properties of the BTSP-borane adduct and its possible employment in H-phosphinic acid syntheses were explored KEYWORDS: Organophosphorus synthesis, silylesters, borane adducts.
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