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Polar ferrocene phosphines with nitrogen-containing linkers
Navrátil, Michal ; Štěpnička, Petr (advisor) ; Dostál, Libor (referee) ; Horáček, Michal (referee)
Title: Polar Ferrocene Phosphines with Nitrogen-Containing Linkers Author: RNDr. Michal Navrátil Supervisor: prof. RNDr. Petr Štěpnička, Ph.D., DSc. Abstract: This Ph.D. thesis describes three series of bridged ferrocene phosphines derived from aminoferrocene. The first series is comprised of homoannular α- and β-aminophosphines 1-3. The α-aminobis(phosphine) 1 was synthesized from aminoferrocene and (diphenylphosphino)- methanol via phospha-Mannich reaction in a 87% yield. This product was formed regardless of the reaction stoichiometry. Later, ligand 1 was utilized as a ligand for group 10 and 11 metal ions. With group 10 metal precursors, the ligand afforded five different square-planar complexes [MX2(1-κP)] (M/X = Ni/Cl, Pd/Cl, Pd/Br, Pd/I, Pt/Cl). In contrast, the complexes of group 11 metals showed varied geometry around the metal centre, ranging from a linear arrangement in [Au2Cl2(1-κP)], cyclic structure in [Au2(1-κP)2][SbF6]2 and tetrahedral arrangement in [M(1-κP)2][X] (M/X = Cu/BF4; Ag/SbF6; Au/SbF6). The cyclic voltammetry measurements suggested that Fe(II) oxidation is the first oxidation process. The attribution was corroborated by DFT calculations of 1 and [PdCl2(1-κP)]. To obtain the analogous monophosphine 2, aminoferrocene was N-methylated prior to the phospha-Mannich reaction. Subsequent...
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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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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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