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Copper(I) complexes with phosphinonitrile donors
Horký, Filip ; Štěpnička, Petr (advisor) ; Kubíček, Vojtěch (referee)
Title: Copper(I) complexes with phosphinonitrile donors Author: Bc. Filip Horký Department: Department of Inorganic chemistry Supervisor: prof. RNDr. Petr Štěpnička, Ph.D. Abstract: Although coordination compounds with phosphinonitrile ligands are already well known, in the vast majority of these complexes these ligands coordinate as simple P-donors with their cyano groups acting as auxiliary substituents. This led us to synthesize and study a series of Cu(I) complexes with two isomeric phosphinonitrile donors, namely 2-(diphenylphosphino)benzonitrile (Lo ) and 2-(diphenylphosphino)benzonitrile (Lp ), with different ligand-to-metal ratios and possibly characterize further coordination modes offered by these hybrid donors. This work describes the preparation of phosphinonitrile complexes from the aforementioned ligands and simple copper(I) halides (CuX, X = Cl, Br, I), pseudohalides (X = CN) and from [Cu(MeCN)4][BF4]. The products were characterized by nuclear magnetic resonance, infrared spectroscopy and elemental analysis, mass spectrometry, and their solid-state structures were determined by single-crystal X-ray crystallography. In addition, luminescent properties of the Cu(I) complexes were studied and catalytic activity of selected complexes was tested in copper-catalyzed alkyne-azide cycloaddition...
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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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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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Deposited palladium catalysts
Semler, Miloslav ; Štěpnička, Petr (advisor) ; Balcar, Hynek (referee) ; Bulánek, Roman (referee)
Palladium catalysts are frequently used in C-C coupling reactions. The aim of this work is to prepare several heterogeneous palladium catalysts from comercially available silica gel, each with different bifunctional ligand deposited on the surface of silica gel by N-propylamide linking group, and their testing on several C-C coupling reactions (Heck reaction, reaction of acyl chlorides with boronic acids and reaction of acyl chlorides with terminal acetylenes). Some other aspects of heterogeneous catalysis (such as palladium leaching into the reaction mixture and possibility of catalyst reuse) are discussed, too. Powered by TCPDF (www.tcpdf.org)
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Phosphinoferrocene ligands with polar amide substituents
Charvátová, Hana ; Štěpnička, Petr (advisor) ; Trávníček, Zdeněk (referee) ; Jambor, Roman (referee)
Title: Phosphinoferrocene ligands with polar amide substituents Author: Hana Charvátová Department: Department of Inorganic Chemistry Supervisor: prof. RNDr. Petr Štěpnička, Ph.D. Abstract: This thesis is focused on phosphino-urea ferrocene ligands that are still rather neglected in the literature. It describes the synthesis of novel polar amides and hydrazides of 1'-(diphenylphosphino)ferrocene-1-carboxylic acid (Hdpf) with or without ethylene linker bearing various urea and guanidine terminal functional groups. Urea and guanidine derivatives with ethylene bridge can be prepared from Hdpf and appropriate amine with amidation agents. Phosphine ureas without the linker are accessible from reactions of primary amide of Hdpf with suitable acylation agents while analogical guanidine is obtained from guanylation of amide-amine generated from Hdpf acylbenzotriazole and ethylenediamine. Reaction of the acylbenzotriazole with free guanidine leads to [1-(diphenylphosphino)ferrocenecarbonyl]guanidine hydrochloride. These ferrocene ligands were used to prepare four types of palladium(II) complexes, viz. where L denotes the newly synthesized ligands and LNC is 2- [(dimethylamino)methyl]phenyl-C,N auxiliary chelating ligand. Catalytic efficiency of complexes with ethylene bridge was tested on reactions of aromatic...
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Preparation of titanium and zirconium metallocene complexes with pendant nitrile groups
Večeřa, Miloš ; Štěpnička, Petr (advisor) ; Vojtíšek, Pavel (referee)
Preparation of metallocene complexes of titanium and zirconium with pendant nitrile groups Miloš Večeřa bachelor thesis Abstract: Two cyclopentadienide salts with pendant nitrile groups were prepared in the form of their corresponding lithium salts and these salts were utilized for the preparation of titanium and zirconium metallocene complexes. One of the ligands was already described in the literature, while the other as well as all the prepared group 4 metallocene complexes are new compounds. Starting materials for these syntheses were 6,6-dimethylfulvene and spiro[2.4]hepta-4,6-diene which, upon a nucleophilic attack by 2-lithio-2-methylpropanenitrile, afforded the corresponding substituted lithium cyclopentadienides, which were characterized by 1 H and 13 C NMR spectroscopy and infrared spectroscopy. Then lithium salts were reacted with Cp*TiCl3 and Cp*ZrCl3 to give the corresponding metallocene dichlorides. Solid-state structures of the prepared titanocene dichlorides were elucidated by means of single crystal X-ray diffraction analysis. The obtained structures allowed a comparison with the known structures of the previously prepared homologous derivative. Unfortunately the corresponding zirconocene dichlorides did not crystallize. Moreover, all the newly prepared metallocenes were characterized by 1...
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Synthesis, characterization and catalytic application of novel zeolites
Eliášová, Pavla ; Čejka, Jiří (advisor) ; Štěpnička, Petr (referee) ; Mintova, Svetlana (referee)
The PhD thesis concerns the synthesis of novel zeolite materials, investigation of their properties and their possible use in catalytic application. The work was focused on the two- dimensional zeolites. The thesis was worked out at the Department of Synthesis and Catalysis at J. Heyrovský Institute of Physical Chemistry, AS CR. Germanosilicate UTL (Si/Ge molar ratio 4.0-6.5) was found to undergo unique structural changes in the neutral or acid environment leading to transformation of its three-dimensional framework into two-dimensional layered material denoted IPC-1P. The UTL degradation, so called top-down synthesis, was enabled due to a presence of double-four-units (D4Rs), which can be seen as supporting units/pillars between the rigid layers. The preferential location of Ge in D4Rs makes the units an ideal target for their selective degradation. The interlayer space in lamellar IPC-1P was modified by swelling with long-organic chain surfactant (material IPC-1SW). To keep the interlayer space permanently expanded (up to 3.3 nm) the silica amorphous pillars were subsequently introduced (material IPC-1PI). The integrity of the layers and their preserved UTL character was confirmed in all members of IPC-1 family by HRTEM and electron diffraction measuring. The layers of IPC-1P were condensed back...
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