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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...
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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.
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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.
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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.
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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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MRI contrast agents based on saturation transfer
Krchová, Tereza ; Kotek, Jan (advisor) ; Štěpnička, Petr (referee)
Title: MRI Contrast Agents Based on Saturation Transfer Author: Bc. Tereza Krchová Department: Department of Inorganic Chemistry, Faculty of Science, Charles University in Prague Supervisor: doc. RNDr. Jan Kotek, Ph.D. Supervisor's email: modrej@natur.cuni.cz Abstract: The aim of this thesis was to synthesize macrocyclic ligands (based on the DO3A and DO2A framework) with exchangeable protons on the aminic coordinating groups that could be (after the complexation with suitable paramagnetic metal ions) potential contrast agents based on saturation transfer, so called CEST contrast agents (Chemical Exchange Saturation Transfer). Two ligands H3L1 and H2L2 with one and two aminoethyl groups have been synthesized. The structurally similar ligands H3L1 Me and H3L1 2Me with one exchangeable proton and without it have been also prepared. The protonation constants of the ligands H3L1 and H2L2 have been determined by pH 1 H NMR and potentiometric titrations. The stability constants of metal ion complexes with H3L1 and H2L2 have been also determined by potentiometry. The CEST effect of Eu3+ and Yb3+ complexes with H3L1 , H3L1 Me and H3L1 2Me in solution have been studied. The residence lifetime of the inner-sphere water molecule has been determined for Gd-L1 complex. Keywords: CEST, MRI, aminoethyl, DO3A, DO2A, 17 O...
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Synthesis and catalytic properties of ferrocenophane phosphines
Škoch, Karel ; Štěpnička, Petr (advisor) ; Veselý, Jan (referee)
6 Title: Sythesis and catalytic properties of ferrocenophane phosphines Author: Karel Škoch Institution: Faculty of Science, Charles University in Prague, Department of Inorganic Chemistry Supervisor: prof. RNDr. Petr Štěpnička, Ph.D. Keywords: ferrocene, ferrocenophane, phosphine ligands, palladium, asymetric catalysis, aza- Morita-Baylis-Hillman reaction, asymetric allylic alkylation Abstract: This Thesis describes the preparation of five sterically and electronically different ferrocene phosphines, (R)-1,1'-[1-(diarylphosphino)propan-1,3-diyl]ferrocenes (R)-1a-e, and a study into their coordination and catalytic properties. The key precursor of the phosphine synthesis, chiral alcohol (R)-2, was prepared according to the procedure described in the literature. Alcohol (R)-2 was converted with retention of configuration to diarylphosphines (R)-1a-e in one-step reaction with trimethylsilylchloride and sodium iodide and then with the corresponding diarylphosphine. Phosphines 1a-e were characterized by NMR and MS methods. For the basic representative 1a the following palladium(II) complexes were prepared: [PdCl(LNC )(1a)] (10, LNC = 2-[(dimethylamino)methyl]phenyl-C1 ,N) and trans- [PdCl2(1a)2] (9a). In addition, the isomeric complex cis-[PdCl2(1a)2] (9b) was isolated from the reaction mixture after catalytic...
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Alternative synthesis of of 1-(diphenylphosphino)-1'-(N,N-dimethylaminomethyl)ferrocene
Zábranský, Martin ; Štěpnička, Petr (advisor) ; Vojtíšek, Pavel (referee)
An alternative, more straightforward and effective method for the preparation of 1- (diphenylphosphino)-1'-(N,N-dimethylaminomethyl)ferrocene was developed using 1-bromo- 1'-(diphenylphosphino)ferrocene as the starting material and Eschenmoser's salt as an aminomethylation agent. Purity of thus prepared phosphinoamine was verified by 1 H and 31 P NMR spectroscopy and by comparison of the data with those reported in the literature (M. E. Wright, Organometallics, 1990, 9, 853). The coordination chemistry of this compound was investigated in gold(I) complexes. Thus, chlorido[1-(diphenylphosphino)-1'-(N,N-dimethyl- aminomethyl)ferrocene]gold(I) complex was synthesized and converted to ill-defined [1- (diphenylphosphino)-1'-(N,N-dimethylaminomethyl)ferrocene]gold(I) perchlorate by halogen abstraction with AgClO4. Protonization of the nitrogen atom in both compounds with hydrogen chloride yielded the corresponding hydrochlorides. It was shown that 1- (diphenylphosphino)-1'-(N,N-dimethylaminomethyl)ferrocene is coordinated as a simple phosphine in the resulting complexes while its amine nitrogen is protonated. All these complexes were characterized by means of 1 H, 31 P and 13 C NMR spectroscopy, mass spectroscopy with electrospray ionisation, elemental analysis and by single-crystal X-ray diffraction analysis.
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Functional phosphinoferrocene carboxamides
Schneiderová, Barbora ; Štěpnička, Petr (advisor) ; Vojtíšek, Pavel (referee)
Functionalized amides 3 and 4 were prepared by the reaction of 1'-(diphenylphosphino)ferrocene-1- carboxylic acid (Hdpf) with 2-(diphenylphosphino) ethylamine or 2-N,N'- (dimethylamino)ethylamine. The amides were converted to their respective phosphinsulfides 5 and 6. Addition of MeI to the solution of 6 gave ammonium salt 7 which, after desulfuration with Raney nickel afforded ammonium salt 8. Compounds 3-8 were characterized by NMR and IR spectroscopy and by MS spectrometry. Phosphine sulfides 6 and polar amides 7 and 8 were structurally characterized. Amides 3, 4 and 8 were tested as ligands in Pd-catalyzed Suzuki-Miyaura coupling reaction of phenylboronic acid with 4-bromacetophenone in organic solvent, water and in biphasic system. Amides 3 and 4 and the related amides 1'-(diphenylphosphanyl)-1-[N-{3- (diphenylphosphino)propyl)}carbamoyl]ferrocene(1) and 1'-(diphenylphosphanyl)-1-[N-(3- dimethylaminopropyl)carbamoyl] ferrocene (2) were reacted with [(COD)PdCl2] to afford palladium complexes of the general formula [(L)PdCl2]. These compounds were characterized by NMR and IR spectroscopy and by MS spectrometry and, for selected representatives, also by X-ray diffraction analysis. Keywords: ferrocene, phosphinoamides, palladium, coordination study, catalysis, Suzuki-Miyaura cross-coupling reaction.
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Deposited palladium catalysts for C-C bond forming reactions
Semler, Miloslav ; Štěpnička, Petr (advisor) ; Sedláček, Jan (referee)
Palladium based catalysts are widely used for C-C bonding reactions. This work describes the preparation of several such catalysts deposited onto siliceous, SBA-15 type support and common silica gel, whose surface was modified by organic chains with amine donor groups. The prepared catalysts have been tested in coupling reactions of organotin compounds and organic halides (Stille reactions) under various conditions.
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