National Repository of Grey Literature 78 records found  beginprevious54 - 63nextend  jump to record: Search took 0.01 seconds. 
Salts of 2-aminoethanol and ferrocene-based acids
Zábranský, Martin ; Štěpnička, Petr (advisor) ; Němec, Ivan (referee)
Combination of the compact but sterically flexible ferrocene scaffold with intermolecular binding potential and conformational variability of (2-hydroxyethyl)ammonium structural motif was utilised in the construction of solid crystalline materials. Crystallisation in systems containing ferrocenecarboxylic, 2-ferrocenylacetic, 3-ferrocenylpropionic, 3-ferrocenyl- acrylic, 3-ferrocenylacrylic, 3-ferrocenylpropiolic, ferrocene-1,1'-dicarboxylic or ferrocene- sulfonic acid with 2-aminoethanol afforded crystals of the corresponding salts. The resulting crystalline products were characterised with the usual methods (proton nuclear magnetic resonance, infrared spectroscopy, elemental analysis) and their crystal structures were determined by means of single-crystal X-ray diffraction analysis. The crystal structures of the salts mentioned above usually contain rather complicated two dimensional networks of charge-assisted hydrogen bonds. With the aim of studying potentially more simple hydrogen-bonded structures, additional crystallisation experiments were conducted in systems of ferrocenecarboxylic acid and 2-(methylamino)ethanol or 2-(dimethylamino)ethanol. These experiments yielded simple salt of the former amine and adducts of salts of both bases with ferrocenecarboxylic acid in the ratio of 1:1. The...
Orgonophosphorus analogues of triphosphate
Šrein, Jakub ; Kubíček, Vojtěch (advisor) ; Štěpnička, Petr (referee)
Two substances were prepared in this work, both with PCPCP structure motif. The motif is similar to ATP molecule, although the oxygen bridges are replaced with methylene groups. Both compounds were characterized by mass spectrometry and NMR spectroscopy. Since bis(methylenephosphonato)phosphinate is soluble in water, four pKa values were determined. Both prepared compounds have potential to serve as chelating ligands. Powered by TCPDF (www.tcpdf.org)
Polar ligands derived from a phosphinoferrocene hydrazide
Vašíček, Tomáš ; Štěpnička, Petr (advisor) ; Schulz, Jiří (referee)
Title: Polar ligands derived from a phosphinoferrocene hydrazide Author: Tomáš Vašíček Institution: Faculty of Science, Charles University in Prague, Department of Inorganic Chemistry Supervisor: prof. RNDr. Petr Štěpnička, Ph.D. This thesis describes the syntheses of three new ligands derived from a phosphinoferrocene hydrazide, namely 1'-(diphenylphosphino)ferrocene-1-carbohydrazide. The reaction conditions were optimized by varying the reaction time and temperature in order to achieve high yields and purity of the products. Newly prepared compounds that bear extended polar groups were characterized by NMR spectroscopy, mass spectrometry, infrared spectroscopy and by elemental analysis. Additionally, the molecular structure of 1'-(diphenylphosphino)-1- {[2-(aminocarbonyl)hydrazino]-carbonyl}ferrocene (8) was determined by X-ray diffraction analysis. Key words: Ferrocene, Phosphines, Hydrazides
Synthesis of a ferrocenyl-substituted bicyclic phosphite
Bárta, Ondřej ; Štěpnička, Petr (advisor) ; Kubíček, Vojtěch (referee)
Title: Synthesis of a ferrocenyl-substituted bicyclic phosphite Author: Ondřej Bárta Institution: Faculty of Science, Charles University in Prague, Department of Inorganic Chemistry Supervisor: prof. RNDr. Petr Štěpnička, Ph.D. This thesis describes the synthesis of a novel bicyclic phosphite ester, {N-(2,6,7-trioxa-1-phosphabicyclo[2.2.2]oct-4-yl)carbamoyl}ferrocene (3). This compound was obtained by the reaction of phosphorus trichloride with the appropriate tris(hydroxymethyl)methyl-amide in the presence of triethylamine or pyridine. The reaction conditions were optimized by varying the solvent, reaction temperature and the base to achive the highest possible yield of the product and to enable its easy and effective chromatographic purification. A new compound, 2-ferrocenyl-4,4-bis(chloromethyl)-4,5-dihydro-1,3-oxazol (4), was isolated as the by-product of this reaction. Compound 3 was further used to prepare the carbonyl complex cis-[W(CO)4(3-κP)2] (5). All the newly prepared compounds were characterized by NMR spectroscopy, mass spectrometry, infrared spectroscopy and by elemental analysis, and their molecular structures were determined by X-ray diffraction analysis. Hydrogen bonds are cooperating to form one-dimensional chains in the crystals of phosphite 3 and solvate 4 × ½ H2O or...
Synthesis and characterization of ferrocenylated amidophosphine
Horký, Filip ; Štěpnička, Petr (advisor) ; Kubíček, Vojtěch (referee)
Title: Synthesis and characterization of ferrocenylated amidophosphine. Author: Filip Horký Department: Department of Inorganic chemistry Supervisor: prof. RNDr. Petr Štěpnička, Ph.D. Abstract: Complexes with amidophosphine donors have found interesting applications in catalysis and in medicinal chemistry. This led us to synthesize {[(2-(diphenylphosphino) ethyl)]-amino]carbonyl}ferrocene (compound 1) and the corresponding phosphine oxide (compound 2). This work describes three new synthetic routes to the target amidophosphine 1. The first one is a simple reaction of ferrocenecarboxylic acid with 2-(diphenylphosphino)ethylamine with reagents mediating amide bond formation. The second approach is based on the reaction of the mentioned amine with the respective acylbenzotriazole. Finally, the third way makes use of the reaction between the amine and an active ester, pentafluorophenyl ferrocencarboxylate. All products and intermediates were characterized by NMR spectra. The newly prepared phosphine oxide 2 was further characterized by infrared spectroscopy, elemental analysis, mass spectrometry and its crystal structure was determined by single-crystal X-ray crystallography. Keywords: ferrocene ligands, ferrocene, phosphine, amide, phosphineoxide, synthesis.
Polar ferrocene amidophosphines for catalytic applications
Schulz, Jiří ; Štěpnička, Petr (advisor) ; Růžička, Aleš (referee) ; Čermák, Jan (referee)
5 Abstract The formerly reported hydroxyamide Ph2PfcC(O)NHCH2CH2OH 1 and its respective novel congeneric analogues Ph2PfcC(O)NHCH3−n(CH2OH)n (3: n = 2; 4: n = 3) were used to prepare a series of arene-ruthenium(II) complexes [(η6 -arene)RuCl2(L-κP)] 6-8 (arene = C6H6, p-cymene, C6Me6; L = 1, 3 or 4). These complexes were studied as pre-catalysts in redox isomerization of allylic alcohols to carbonyl compounds. Among the compounds prepared, complex 6b [(η6 -p-cymene)RuCl2(1-κP)] showed best results. The solid state structure of the product of photolytic decomposition of complex [(η6 - C6Me6)RuCl2(2-κP)] (2 = Ph2PfcC(O)N(CH2CH2OH)2), viz, [(µ-Cl)3{Ru(η6 -C6Me6)}2] [FeCl4] 9, was determined by single-crystal X-ray diffraction analysis. The bis-phosphane complexes [MII Cl2(1-κP)2] (M = trans-Pd (10), cis-Pt (11) and trans- Pt (12)) together with chalcogenide derivatives Ph2P(O)fcC(O)NH(CH2)2OH (13) and Ph2P(S)fcC(O)NH(CH2)2OH (14) derived from hydroxyamide 1 were tested in vitro for their cytotoxicity against human ovarian A2780 cancer cell line. Complexes tested showed moderate cytotoxicity. Triol-amide FcC(O)NHC(CH2OH)3 15 (Fc = ferrocenyl) reacted with decavanadate (Bu4N)2[H3V10O28] at elevated temperature and prolonged reaction time yielding the hybrid hexavanadate (Bu4N)2[{FcC(O)NHC(CH2O)3}2V6O13] 16...
Synthesis and properties of a ferrocenyl-substituted diphosphine
Verníček, Marek ; Štěpnička, Petr (advisor) ; Vojtíšek, Pavel (referee)
Title: Synthesis and properties of a ferrocenyl-substituted diphosphine Author: Marek Verníček Department: Department of Inorganic Chemistry (Faculty of Science, Charles University in Prague) Supervisor: prof. RNDr. Petr Štěpnička, Ph.D. In this work, a new ligand was prepared, namely N,N-bis[2-(difenylfosfino)ethyl]amide of ferrocenecarboxylic acid. This ligand was obtained by the reaction of pentafluorophenylferrocenecarboxylate, which was newly synthesized, with the appropriate amine. The ligand was characterized by 1 H, 13 C, 31 P NMR spectroscopy, elemental analysis, IR spectroscopy and by mass spectrometry. Subsequently, a sulphide was prepared from this diphosphine-amide by the reaction with sulfur in toluene at elevated temperature. The sulphide was characterized in the same manner and also analyzed by single-crystal X-ray diffraction analysis. The coordination properties of the ligand were examined in a reaction with [PtCl2(cod)] (cod = cyclooctadiene) in dichloromethane. The resulting complex was studied by 1 H NMR, mass spectrometry, elemental analysis and by X-ray structural analysis. Keywords: ferrocene; phosphine ligands; amidophosphines; platinum(II) complexes; crystal structure.
Palladium catalysts deposited over novel siliceous supports
Křečková, Pavlína ; Štěpnička, Petr (advisor) ; Sedláček, Jan (referee)
Title: Palladium catalysts deposited over novel siliceous supports Author: Pavlína Křečková Department: Department of Inorganic Chemistry, Faculty of Science, Charles University in Prague Supervisor: prof. RNDr. Petr Štěpnička, Ph.D. Supervisor's e-mail address: stepnic@natur.cuni.cz Advisor: prof. Ing. Jiří Čejka, DrSc. Advisor's e-mail address: jiri.cejka@jh-inst.cas.cz Abstract Keywords: palladium; deposited catalysts; siliceous supports; C-C coupling reaction. The aim of this work was to prepare a deposited palladium catalyst from Pd2+ and twodimensional zeolite ITQ-2 bearing ≡SiCH2CH2CH2NHCH2CH2NEt2 groups at the surface. This catalys has been evaluated in the Heck reaction between n-butyl-acrylate and brombenzene to give n-butyl-cinnamate. Influence of the reaction temperature, the solvent, base and hydrate water on the progress of the Heck reaction was investigated. This work also deals with the possibility of recycling the catalyst and, due to its nature, with the quantity of leached palladium into the reaction mixture. Furthermore, the work describes differences in morphology between the fresh and a recycled catalyst.
Catalytic testing of polar amidophosphines
Šrámková, Helena ; Štěpnička, Petr (advisor) ; Veselý, Jan (referee)
Catalytic testing of polar amidophosphines: abstract A series of new nine arylruthenium complexes [(aryl)RuCl2(L)] was studied in isomerisations of allylic alcohols to carbonyl compounds. The best reaction conditions were found. The best solvent and reaction temperature were chosen. The best amount of catalyst and the best base and its amount were chosen too. In these conditions, the catalysts were tested for four substituted allylic alcohols. It was proven that these catalysts isomerise readily simple allylic alcohols, but not substrates that is highly substituted.
Phosphinoferrocene conjugates of selected amino acids
Tauchman, Jiří ; Štěpnička, Petr (advisor) ; Růžička, Aleš (referee) ; Dvořák, Dalimil (referee)
A series of chiral phosphinoferrocene amides was prepared by the condensation either of 1'- (diphenylphosphino)ferrocene-1-carboxylic acid (Hdpf) or its planar-chiral 1,2-isomers and amino acid methyl esters in the presence of peptide coupling agents. The resulting phosphinoamides were tested as ligands in Cu-catalyzed asymmetric conjugate additions of diethylzinc to chalcones and in Pd-mediated asymmetric allylic substitution reactions of 1,3- diphenylallyl acetate with the respective nucleophile (alkylation, amination and etherification). The catalytic tests were focused on an optimization of the reaction parameters (solvent, temperature, base, metal/ligand ratio) and on survey of various substrates. Compounds based on Hdpf proved to be better ligands in both catalytic reactions than their planar chiral analogues. In order to rationalize the influence of the ligand structure on the reaction course and also to interpret the catalytic results, several model complexes were prepared and structurally characterized. Other three series of non-chiral complexes were prepared from the corresponding (η6 - arene)ruthenium(II) precursor and Hdpf-glycine conjugates; the neutral complexes of the type [(arene)RuCl2(Hdpf-Gly(R)-κP)] (arene = benzene, p-cymene, hexamethyl-benzene; R = OMe, NH2, OH) as well as two...

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