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Polar phosphinoferrocene ligands with hydrocarbyl bridges
Zábranský, Martin ; Štěpnička, Petr (advisor) ; Dostál, Libor (referee) ; Šebesta, Radovan (referee)
A new synthetic route towards methylene-spaced hybrid phosphinoferrocene ligands was developed, making use of a phosphinoferrocene betaine 3-(N,N,N-{[1'-(diphenylphosphino)- ferrocenyl]methyl}dimethylammonium)propane-1-sulfonate (2), that is readily accessible from 1-(diphenylphosphino)-1'-(N,N-dimethylaminomethyl)ferrocene (XIX) via treatment with 1,3-propanesultone. The betaine 2 was reacted with sodium alkylsulfinates (alkyl = methyl, phenyl, 4-tolyl) to afford the corresponding sulfones 4. The coordination chemistry of [1'-(diphenylphosphino)ferrocenyl]methyl(methyl)sulfone (4a) was investigated in its zinc(II) complexes. Surprisingly, only insoluble mixed-metal coordination polymers of the general formula [MZnX3(4a)(MeOH)]n (M/X = Na/Br, K/Br, Na/I) and six-centre complex [Li2Zn2Br6(4a)2(MeOH)4(H2O)] could be obtained. Two isomeric homologues of 1'-(diphenylphosphino)ferrocene-1-carboxylic acid (Hdpf, II), viz. 1'-(diphenylphosphino)ferrocenylacetic acid (HIIa) and 1'- [(diphenylphosphino)methyl]ferrocene-1-carboxylic acid (HIIb), were prepared and their coordination preferences were assessed in their palladium(II) complexes. The palladium(II) complexes were prepared by reacting various (acetylacetonate)palladium(II) precursors with these acids with concomitant release of acetylacetone....
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Electronically dissymmetric ferrocene bisphosphines
Horký, Filip
This Thesis describes the synthesis, reactivity, coordination properties, and catalytic activity of novel electronically dissymmetric bisphosphines structurally related to 1,1'-bis(diphenylphosphino)ferrocene (dppf). First, a methylene spaced congener containing a primary phosphine group, which is stable in the air, Ph2PfcCH2PH2 (fc = ferrocene-1,1'-diyl), was prepared. While studying its reactivity, an unprecedented stable primary phosphine oxide, Ph2PfcCH2P(O)H2, was isolated. The primary phosphine, the corresponding phosphine oxide, dppf and the known bis-tertiary phosphine Ph2PfcCH2PPh2 were studied as ligands in Ru(II) complexes. The catalytic activity of the defined complexes was compared in two ruthenium-catalyzed reactions: cyclization of (Z)-3-methylpent-2-en-4-yn-1-ol into 2,3-dimethylfuran and isomerization of estragole to anethole. Second, the remarkable stability of the prepared primary phosphine oxide called for a detailed investigation of this poorly described class of compounds. As a result, stable primary phosphine chalcogenides lacking steric protection FcCH2P(Y)H2 (Fc = ferrocenyl; Y = O, S, Se) were isolated for the first time. These compounds were studied as ligands in reactions with hard and soft Lewis acids (Zn(II) and Ru(II)), and the reactivity of the P-H hydrogens was...
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Electronically dissymmetric ferrocene bisphosphines
Horký, Filip ; Štěpnička, Petr (advisor) ; Horáček, Michal (referee) ; Šebesta, Radovan (referee)
This Thesis describes the synthesis, reactivity, coordination properties, and catalytic activity of novel electronically dissymmetric bisphosphines structurally related to 1,1'-bis(diphenylphosphino)ferrocene (dppf). First, a methylene spaced congener containing a primary phosphine group, which is stable in the air, Ph2PfcCH2PH2 (fc = ferrocene-1,1'-diyl), was prepared. While studying its reactivity, an unprecedented stable primary phosphine oxide, Ph2PfcCH2P(O)H2, was isolated. The primary phosphine, the corresponding phosphine oxide, dppf and the known bis-tertiary phosphine Ph2PfcCH2PPh2 were studied as ligands in Ru(II) complexes. The catalytic activity of the defined complexes was compared in two ruthenium-catalyzed reactions: cyclization of (Z)-3-methylpent-2-en-4-yn-1-ol into 2,3-dimethylfuran and isomerization of estragole to anethole. Second, the remarkable stability of the prepared primary phosphine oxide called for a detailed investigation of this poorly described class of compounds. As a result, stable primary phosphine chalcogenides lacking steric protection FcCH2P(Y)H2 (Fc = ferrocenyl; Y = O, S, Se) were isolated for the first time. These compounds were studied as ligands in reactions with hard and soft Lewis acids (Zn(II) and Ru(II)), and the reactivity of the P-H hydrogens was...
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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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Polar phosphinoferrocene ligands with hydrocarbyl bridges
Zábranský, Martin ; Štěpnička, Petr (advisor) ; Dostál, Libor (referee) ; Šebesta, Radovan (referee)
A new synthetic route towards methylene-spaced hybrid phosphinoferrocene ligands was developed, making use of a phosphinoferrocene betaine 3-(N,N,N-{[1'-(diphenylphosphino)- ferrocenyl]methyl}dimethylammonium)propane-1-sulfonate (2), that is readily accessible from 1-(diphenylphosphino)-1'-(N,N-dimethylaminomethyl)ferrocene (XIX) via treatment with 1,3-propanesultone. The betaine 2 was reacted with sodium alkylsulfinates (alkyl = methyl, phenyl, 4-tolyl) to afford the corresponding sulfones 4. The coordination chemistry of [1'-(diphenylphosphino)ferrocenyl]methyl(methyl)sulfone (4a) was investigated in its zinc(II) complexes. Surprisingly, only insoluble mixed-metal coordination polymers of the general formula [MZnX3(4a)(MeOH)]n (M/X = Na/Br, K/Br, Na/I) and six-centre complex [Li2Zn2Br6(4a)2(MeOH)4(H2O)] could be obtained. Two isomeric homologues of 1'-(diphenylphosphino)ferrocene-1-carboxylic acid (Hdpf, II), viz. 1'-(diphenylphosphino)ferrocenylacetic acid (HIIa) and 1'- [(diphenylphosphino)methyl]ferrocene-1-carboxylic acid (HIIb), were prepared and their coordination preferences were assessed in their palladium(II) complexes. The palladium(II) complexes were prepared by reacting various (acetylacetonate)palladium(II) precursors with these acids with concomitant release of acetylacetone....
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Functional phosphinoferrocene ligands
Škoch, Karel ; Štěpnička, Petr (advisor) ; Grüner, Bohumír (referee) ; Dostál, Libor (referee)
6 Abstract The first part of this Thesis describes the preparation of a novel phosphanyl-ferrocene amine, Ph2PfcCH2NH2 (1; fc = 1,1'-ferrocendiyl) in two steps from the known aldehyde Ph2PfcCHO. An oxime Ph2PfcCH=NHOH was prepared firstly by a condensation reaction, and subsequently treated with Li[AlH4] to give the desired amine. The amine was converted into its more stable hydrochloride salt, Ph2PfcCH2NH3Cl. Derivatization of amine 1 was examined through the preparation of a series of phosphanyl-urea ligands Ph2PfcCH2NHC(E)NR1 R2 . Some of these compounds were also prepared via an alternative method employing reductive amination reaction. These donors and their Pd(II) complexes were evaluated in Pd-catalyzed reaction of arylbromides with K4[Fe(CN)6] in order to prepare corresponding benzonitrile derivatives using aqueous reaction solvents. The reaction proceeds with excellent yields and purity when 1 mol.% of Pd- catalyst is used (at 100 řC for 3 hours), especially for electron-rich bromobenzenes. Substrates with electron-withdrawing substituents react significantly slower and corresponding hydrolytic products (benzamides) are isolated. The coordination properties of phosphanyl-amine 1 were examined towards Cu(I) ions. Thus, reaction of 1 with [Cu(MeCN)4][BF4] provided bis-chelate complex [Cu(1- κ2...
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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...
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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.
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