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Preparation and characterization of crystalline materials - salts of N-guanylglycinium and guanidinium
Skopalík, Jiří ; Matulková, Irena (advisor) ; Zákutná, Dominika (referee)
The scope of this bachelor thesis is the preparation and study of new salts, which can be obtained from systems N-guanylglycine - inorganic acid and guanidine - amidosulfuric acid, as new materials with potential for applications in nonlinear optics. Prepared crystalline salts of N-guanylglycinium - i.e. chloride, two hydrogenphosphites and sulfate dihydrate along with guanidinium amidosulfate were characterized by methods of vibrational spectroscopy (infrared and Raman) and X-ray diffraction (single crystal and powder methods). To estimate the nonlinear optical properties and for the interpretation of the vibrational manifestations of N-guanylglycinium cation, quantum-chemical calculations were performed. Finally, for two non-centrosymmetric N-guanylglycinium hydrogenphosphites, the efficiency of second harmonic generation was determined for powder samples.
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Coordination properties of a 2-(diphenylphosphino)guanidine ligand
Leitner, Zdeněk ; Štěpnička, Petr (advisor) ; Lamač, Martin (referee)
Title: Coordination properties of phosphinoguanidine ligand Author: Bc. Zdeněk Leitner Institution: Faculty of Science, Charles University in Prague, Department of Inorfanic Chemistry Supervisor: prof. RNDr. Petr Štěpnička, Ph.D., DSc. Polar phosphine ligands have found use in variety of homogenous and biphasic catalytic processes. In the past, extensive research has been performed also on cationic phosphines, namely phosphinoguanidinium salts. However, neutral phosphinoguanidines have been mostly neglected and their coordination chemistry has not been described to a satisfactory extent, even though the combination of soft phosphorous and harder nitrogen Lewis base could exhibit interesting properties, mainly hemilabile coordination, as well as protonation-controlled nitrogen coordination. These properties could have a positive impact on catalytical performance of this ligand in systems, which benefit from hydrogen bonding or the presence of basic guanidine group. The aim of this work was to study coordination properties of an earlier prepared ligand L and the corresponding phosphinoguanidine salt L·HCl in reactions with Group 11 metal precursors. New compounds were characterized, and their crystal structures were determined. In addition to conventional compounds, an uncommon dimeric complex...
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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...
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Ferrocene phosphinoguanidine donors
Bárta, Ondřej ; Štěpnička, Petr (advisor) ; Dostál, Libor (referee) ; Hoskovcová, Irena (referee)
The "Ferrocene phosphinoguanidine donors" project presented in this Thesis targeted on the synthesis, coordination chemistry and catalytic applications of a rather uncommon class of compounds combining phosphine and guanidine functional groups in their molecules. Two series of such compounds based on ferrocene backbone (henceforth fc = ferrocen-1,1΄-diyl) were studied. Firstly, a reliable synthetic route towards polar phosphinoguanidinium chlorides [R2PfcCH2NHC(NH2)2]Cl, where R = iso-propyl, cyclohexyl, phenyl and 2-furyl, was developed and these ligands were tested as supporting ligands in palladium-catalysed Suzuki-Miyaura-type reactions in biphasic aqueous mixtures and in rhodium-catalysed hydroformylation of 1-hexene. Deduced from the results, the hydrophilic guanidinium tag had a beneficial effect on the catalytic activity and, particularly, the electron-rich phosphines from this series could serve as a useful alternative to commonly used ligands for catalytic applications in polar or aqueous reaction media. Phosphinonitriles R2PfcCN obtained as intermediates during the synthesis of the abovementioned ligands were additionally used for the preparation of the dimeric complexes [Au2(µ-R2PfcCN)2][SbF6]2, in which the gold(I) centre was stabilised by nitrile coordination. These complexes proved...
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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...
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