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1

Nanocząsteczkowe katalizatory palladowe w reakcjach tworzenia wiązań C-C

Trzeciak A. M., Ziółkowski J. J.

Wiadomości Chemiczne

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2009

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[Z] 63, 1-2

1-15

EN

The important role of palladium nanoparticles has been recently demonstrated in many catalytic systems designed for C-C bond forming reactions [1-4]. There are examples of catalytic systems described earlier as homogeneous in which Pd(0) nanoparticles were now identified. In the article three different palladium catalytic systems are discussed. In the first one, Pd(0) nanoparticles, obtained by chemical reduction of PdCl2 and stabilized by polyvinylpyrrolidone, were used for Heck coupling in [Bu4N]Br medium. Decrease of nanoparticles size in reaction conditions was explained as a result of dissolution of Pd(0) colloid and simultaneous formation of catalytically active monomolecular anionic palladium complexes [33]. The second example presents application of Pd(II) and Pd(0) supported on alumina-based oxides in Suzuki-Miyaura reaction [36]. Reduction of Pd(II) to Pd(0) nanoparticles under reaction conditions was confirmed. In contrast to the first described case, in Suzuki-Miyaura reaction the size of Pd(0) nanoparticles was the same before and after the catalytic cycle. The catalytic activity of both palladium forms was quite high, however Pd(0) formed in situ was slightly more efficient as catalyst. In the third part of the article studies of palladium reduction in anionic complexes of [IL]2[PdX4] type are shown, where IL = imidazolium cation [37]. These complexes catalyzed well Suzuki-Miyaura cross-coupling, but they were not stable under reaction conditions and decomposed to Pd(0) nanoparticles and Pd black. Using ESI-MS method it was possible to identify polynuclear (Pd3, Pd5) intermediate forms, stabilized with imidazolium cations or N-heterocyclic carbenes. In all systems discussed in the article co-existence of Pd(0) nanoparticles and monomolecular complexes was observed. That is important for understanding of the nature of catalytically active forms in C-C bond forming reactions.

2

Palladium Complexes with Aminophosphine and Aminophosphite Based PNP and PCP Pincer-type Ligands as Catalysts of Heck Reaction

Benito-Garagorri D., Kirchner K., Trzeciak A. M., Mieczyńska E., Ziółkowski J. J.

Polish Journal of Chemistry

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2008

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Vol. 82, nr 9

1687-1687

EN

Pd(II) complexes with aminophosphine-based PNP and PCP pincer type ligands were used as catalysts of Heck coupling of bromobenzenes and styrene at 110 graduate C. The best results were obtained with catalyst I, [Pd(PNP-Ph)Cl]Cl, where PNP = N,N'-bis(diphenyl - phosphino)-2,6-diaminopyridine. Heck reaction performed in the presence of I and [Bu4N]Br as co-catalyst produced in 5 h up to 100% of coupling products with E/Z ratio equal from 8.6 to 33.5. Palladium catalyst I was recycled and used at least 3 times with out remark able decrease of catalytic activity.

3

Homogeniczne i heterogenizowane katalizatory rodowe w reakcjach hydroformylacji związków nienasyconych

Trzeciak A. M., Ziółkowski J. J.

Przemysł Chemiczny

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2006

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T. 85, nr 2

96-100

PL

Przedstawiono ogólne wprowadzenie do szeroko stosowanych w przemyśle procesów hydroformylacji związków nienasyconych (monoolefin, dienów i nienasyconych alkoholi). Podsumowano ponad 25-letnią działalność naukową w zakresie syntezy, badań strukturalnych i reaktywności katalitycznej kompleksów rodu w reakcjach hydroformylacji, izomeryzacji i uwodornienia prowadzonych na Wydziale Chemii Uniwersytetu Wrocławskiego.

EN

A review with 30 refs. covering selected problems of hydroformylation based on studies conducted at the Faculty of Chemistry University of Wroclaw. The influence of P ligand type on the selectivity of hydroformylation of monoolefins, dienes and unsaturated alcohols and the reactivity of rhodium catalysts supported on Al2O3 – ZrO2 and on SiO2 are discussed.

4

Czasopisma chemiczne w Polsce - stan w 2004 r. : próba oceny

Jurczak M., Kijeński J., Ziółkowski J. J.

Wiadomości Chemiczne

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2005

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[Z] 59, 1-2

139--155

EN

The analysis of chemical periodicals in Poland in 2004 have been ordered by Pol ish Academy of Science, the Committe for Chemistry and presented in three parts. In Part 1 (Józef J. Ziółkowski) are presented: - journals of scientifics character, printed in english, english and polish and german (Group A) - journals printed in polish (Group B) - journals printed as scientitics bulletins edited by the univeristes or research institutes (Group C) - popularized scientific or commercial journals (Group D) and - the books publication, special issues usually for didactic purposes (Group E). In Part II (Jacek Kijenski) are disscussed chemical periodicals addressed to science, technology and industrial chemistry mainly related to environmental chemistry, polymers, fuels, energy problems, and raw materials. In Part III (Janusz Jurczak) is presented opinion about location of polish chemical periodicals in Europe. Presented above analysis is probably the first complex valuation and although not complete may stimulate further discussion on strategy of development of chemical periodicals in Poland.

5

Crystal and molecular structure of tetra(triphenylphosphine oxide) sodium hexafluorophosphate

Trzeciak A. M., Lis T., Wojtków W., Ziółkowski J. J.

Bulletin of the Polish Academy of Sciences. Chemistry

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2002

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Vol. 50, No. 1

27-35

EN

The complex compound of [Na(OPPh3)4]PF(6) formula was obtained in the reaction of triphenylphosphine oxide (OPPhs) with sodium hexafluorophosphate (NaPFg) in dichloromethane (CH(2)Cl(2). The slow crystallization at room temperature produced crystals suitable for X-ray analysis. Crystals are triclinic, space group P1 with a = 12.035(3), b= 14.268(3), c = 19.397(4) A, Alfa = 72.72(2), beta = 89.14(2), gamma = 88.29(2)°, V = 3178.9(12 A3 and Z = 2 at 100 K. The sodium cation is surrounded by four oxygen atoms of OPPh(3) ligands in a tetrahedral fashion. The slight difference of Na-O distances (2.207(2)-2.239(2) A) as well as remarkable difference of P-O-Na angles (137.37(7)-172.55(9)°) found in [Na(OPPh3)4J+ cation are explained by formation of intramolecular C-H.. .O interactions as well as intermolecular interactions of C-H.. .F type between phenyl rings and fluorins of PF-(6).

6

O reaktywności chemicznej polieterowego sorbenta SO2

Rybak W., Ziółkowski J. J., Matyschok H.

Prace Naukowe Politechniki Szczecińskiej. Instytut Technologii Nieorganicznej

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1998

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Nr 547

371-375

PL

Przeprowadzono modelowe badania trwałości chemicznej polieterowego sorbenta SO2 na przykładzie tetraglymu CH3(OCH2CH2)4OCH3 w warunkach zbliżonych do pracy w instalacji technologicznej. Na podstawie analizy GC-MS stwierdzono możliwość znacznej destrukcji sorbenta, której stopień zależeć będzie od składu gazów odlotowych i warunków pracy sorbenta. Stwierdzono, że złożone procesy destrukcji polieterów przebiegają zasadniczo według dwóch mechanizmów: rozpadu homolitycznego polegającego na reakcjach wolnorodnikowego autoutleniania z udziałem tlenu atmosferycznego, oraz rozpadu heterolitycznego, polegającego na rozszczepieniu wiązania eterowego z udziałem silnych kwasów Brönsteda (głównie H2SO4) tworzących się w układzie. Oba te procesy destrukcji mogą być katalizowane, np. związkami Cu(II) lub inhibitowane, np. tlenkami arsenu (III)/(V).

EN

The chemical stability of polyoxirane absorbents of SO2 has been investigated in case of tetraglym CH3(OCH2CH2)4OCH3 as model system. Applied reaction conditions were close to those used in wet desulphurization process. Followed by GC-MS analyses of the reaction products abilities of absorbent decomposition has shown. Proportions of these decomposition mainly depend on extent and kind of contamination present in exhausting gases. In principle two mechanisms are responsible for the decomposition. The homolytic degradation is caused by autoxidation reactions followed by dioxygen presence in the system. Second one, is the heterolytic degradation consisting on oxirane arrangement splitting caused by Brönsted acids (mainly H2SO4) formed in the system. Both decomposition processes can be catalysed, e.g. by Cu(II) compounds, or inhibited, e.g. by arsenic (III)/(V) oxides.

7

Katalityczna aktywność układu N-hydroksyftalimid - kokatalizator w reakcji utleniania związków organicznych ditlenem

Sobczak J. M., Ziółkowski J. J.

Prace Naukowe Politechniki Szczecińskiej. Instytut Technologii Nieorganicznej

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1998

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Nr 547

335-338

PL

Zbadano aktywność katalityczną czwartorzędowych soli amoniowych i chlorowodorków niektórych amin jako kokatalizatorów w reakcji utleniania związków organicznych ditlenem katalizowanych przez N-hydroksyftalimid (NHPI). Zbadano wpływ podstawnika alkilowego przy atomie azotu, a na przykładzie soli tetrabutyloamoniowych, wpływ anionu. Szczególnie efektywnymi kokatalizatorami okazały się sole chlorkowe, a w szczególności: Et4NCl, Bu4NCl oraz Et3NHCl, przy czym ilości tych związków są kilkadziesiąt razy mniejsze niż katalizatora (NHPI). Zastosowanie soli amoniowych zdecydowanie wpływa na szybkość procesu utleniania i umożliwia prowadzenie reakcji w łagodniejszych warunkach (niższe temperatury, atmosferyczne ciśnienie ditlenu). Nowy układ katalityczny, oparty na kombinacji NHPI i czwartorzędowej soli amoniowej stwarza interesujące perspektywy opracowania nowej energooszczędnej i bezpiecznej dla środowiska technologii dla procesu utleniania niektórych związków organicznych.

EN

Activity of quaternary ammonium salts and some of teritiary amine hydrochlorides were studied as co-catalysts vs. N-hydroxyphthalimide - catalyst in oxidation reaction of organic compounds by dioxygen. Influence of alkyl substituents at N-atom and different tetrabutylammonium salts were studied. We have found that some of these compounds, e.g. Et4NCl, Bu4NCl or Et3NHCl are very active (reactions were carried on with very low concentration of co-catalyst, at a lower temperature and under normal pressure of oxygen) and are comparable to known system based on NHPI-Co(acac)3. The new catalytic system is very promissing, because eliminating metals is environmental safety.

8

Superoxo rhodium(III) complexes with higher carboxylic and amino-carboxylic acids as ligands

Moszner M., Ziółkowski J. J.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 11

2357-2365

EN

Replacement of H2O and/or OH(-) ligands in the [Rh2(O2(-))(OH)2(H2O)n](3+)cation by carboxylate ions: RCO2(-) (R=C2H5, C3H7, C4H9, (CH3)3), glycine, L-aspartic acid and L-proline have been studied by electronic and ESR spectra. Two new superoxo rhodium(III) carboxylates formulated as [Rh2(O2(-))(OH)(RCO2)4]n, (R=C2H5 (1), C3H7 (2)), have been synthesized in the reaction between the rhodium (III) superoxo hydroxide, assumed to be [Rh2(O2(-))(OH)2+m(H2O)n-m] with RCO2H. Reaction products were characterized by elemental analysis, UV-VIS, IR, ESR spetroscopies and magnetic susceptibility measurements. The results indicated the formation both the superoxo rhodium(III) carboxylates and amino-carboxylates, containing the [Rh2(O2(-))]5+ core of higher stability in the compounds with the amino-carboxylic acid anions.