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Editorial

Rudowicz Cz., Sojka Z., Jezierska J., Pietrzyk P.

Nukleonika

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2015

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Vol. 60, No. 3, part 1

375

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Optical recognition elements. Macrocyclic imidazole chromoionophores entrapped in silica xerogel

Kledzik K., Jamrógiewicz M., Gwiazda M., Wagner-Wysiecka E., Jezierska J., Biernat J. F., Kłonkowski A. M.

Materials Science Poland

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2007

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Vol. 25, No. 4

1041--1051

EN

Materials containing new chromoionophores consisting of crown residue and azole moiety as parts of macrocycles were encapsulated by the sol-gel procedure in silica xerogel matrices and proposed as chemical recognition elements especially for such metal ions as Li+, Cs+ and Cu2+. Action of these recognition elements is in principle based on changes of reflectance. The recognition elements containing 21- membered chromogenic derivatives of unsubstituted imidazole and 4-methylimidazole are able to distinguish in aqueous solution whether the Li+ concentration ratio is lower or higher than 1. In the case of Cu2+ complexes with 18-membered macrocyclic chromoionophore in which phenol residue was replaced by imidazole and 21-membered chromogenic derivative of 4-methylimidazole, values of the EPR parameters g and A suggest participation of two oxygen and two nitrogen atoms of the ligand in the equatorial plane of the tetragonally distorted octahedral environment of the central ion.

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Structural and Spectroscopic Characterization of Mixed Ligand Complex: Bis(quinoline-2-carboxylato)bis(imidazole)manganese(II)

Dobrzyńska D., Jerzykiewicz L., Jezierska J., Słoniec E.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 11

1789-1797

EN

A new complex, [Mn(quin-2-c)2(Him)2] (quin-2-c = quinoline-2-carboxylate ion, Him = imidazole), was synthesized by self assembly and its structure was determined by X-ray analysis. The compound crystallizes in the centrosymmetric space group C2/c with the Mn atom on a twofold axis, a = 18.091(6) Alfa; b = 10.125(4) Alfa; c = 13.708(5) Alfa; Beta= 111.73(3)graduate; V = 2332.5(15) Alfa3 and Z = 4 (T = 100 K). Strong hydrogen bonds between imidazole moieties and carboxylate groups connect themolecules of the complex into the 1D chains extending parallel to the c axis. The interchain contacts of the C-HźźźO, C-HźźźN,piźźźpi and C-Hźźźpi type influence the architecture of the crystal. The complex was characterized by thermal analysis, and by EPR and IR spectroscopy.

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Wpływ budowy polimerowych katalizatorów utleniania na ich aktywność katalityczną

Kolarz B., Jakubiak A., Jezierska J.

Polimery

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2006

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T. 51, nr 7-8

561-570

PL

Zbadano wpływ budowy określonej grupy polimerowych katalizatorów utleniania na ich aktywność katalityczną w modelowej reakcji utleniania hydrochinonu do p-benzochinonu nadtlenkiem wodoru. W tym celu metodą polimeryzacji suspensyjnej otrzymano dwie serie terpolimerów akrylonitrylu (AN) i octanu winylu (VA) usieciowanych bądź diwinylobenzenem (DVB), bądź też triakrylanem (1,1,1)-trihydroksymetylopropanu (TMPA), bądź też trimetakrylanem (1,1,1)-trihydroksymetylopropanu (TMPMA). W zależności od rodzaju monomeru sieciującego powstające usieciowane produkty miały strukturę żelową albo porowatą. Metodą dwustopniową poddano aminolizie hydrazyną grupy nitrylowe terpolimeru, a utworzone na tym etapie hydrazynowe grupy aminowe modyfikowano tiomocznikiem wobec jodku alkilu. Uzyskano nośniki z grupami aminoguanidynowymi, karboksylowymi i hydroksylowymi, których budowę scharakteryzowano metodą FT-IR. Właściwe katalizatory uzyskiwano w wyniku sorpcji jonów Cu(II) przez te nośniki. Porównano stopień przereagowania hydrochinonu (LH2Q), wydajność p-benzochinonu (YQ) jako głównego produktu oraz obliczaną na tej podstawie selektywność (S) (S = YQ/LH2Q) przedstawionych powyżej katalizatorów oraz katalizatorów uzyskanych na drodze jednoetapowej aminolizy terpolimerów węglanem guanidyny lub węglanem aminoguanidyny. Katalizatory usieciowane DVB i poddane jednostopniowej modyfikacji charakteryzowały się największą aktywnością i selektywnością (blisko 100 %). We wszystkich przypadkach katalizatory z grupami aminoguanidynowymi były bardziej aktywne niż katalizatory z grupami hydrazynowymi, niepoddanymi dalszej modyfikacji. Przedstawione wyniki badań świadczą o tym, że o aktywności badanych katalizatorów, w tym także o ich selektywności, decydują warunki sprzyjające powstawaniu kompleksu N2O2 oraz korzystne mikrośrodowisko wytwarzane przez wolne, nieskompleksowane grupy funkcyjne.

EN

The effect of the structure of particular group of polymeric catalysts of the oxidation process on their catalytic activity, in the model reaction of hydroquinone oxidation to p-benzoquinone with hydrogen peroxide, was investigated. Two series of terpolymers of acrylonitril (AN) and vinyl acetate (VA) crosslinked with either divinylbenzene (DVB) or trihydroxymethylpropane triacrylate (TMPA) or trihydroxymethylpropane trimethacrylate (TMPMA) (Table 2) were obtained in suspension polymerization. Dependently on the type of crosslinking monomer the products showed either the gel structure or porous one. In two-stage process the nitrile groups of terpolymer were subjected to aminolysis with hydrazine and amino groups obtained in this way were modified with thiourea in the presence of alkyl iodide (Scheme A). The supports containing aminoguanidyl, carboxyl or hydroxyl groups were obtained (Table 1 and 3) and their structures were characterized using FT-IR method. The proper catalysts were prepared via sorption of Cu(II) ions on these supports. Some parameters of these catalysts and of the catalysts prepared in one-stage aminolysis of terpolymers with guanidine carbonate or aminoguanidine carbonate were compared. They were: hydroquinone conversion degree (LH2Q), yield of quinone (YQ) as a main product and selectivity of the catalysts calculated on this basis (Table 4 and 5, Fig. 5 and 6). The catalysts crosslinked with DVB and subjected to one-stage modification showed the highest activity and selectivity (close to 100 %). In all cases the catalysts with aminoguanidyl groups were more active than those with hydrazine groups not subjected further modification. The results obtained show that the conditions encouraging the formation of N2O2 complexes as well as advantageous microenvironment formed by uncomplexed functional groups determine the activity and selectivity of the catalysts investigated.

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Complexes of uracil (2,4-Dihydroxypyrimidine) Derivatives. Part I. Cu(II), Ca(II) and MG(II) Coordination with Uracil and Related Compounds in Aqueous Solution

Kufelnicki A., Kupińska I., Jezierska J., Ochocki J.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 11

1559-1570

EN

Potentiometric pH studies were carried out on proton and metal (Cu(II), Ca(II) and Mg(II)) complexes of HL = uracil, thymine (5-methyluracil), 6-chloromethyluracil, 5-hydroxymethyluracil, 6-methyluracil and a diethyl 6-uracilmethylphosphonate derivative. For Cu(II) additional spectroscopic (absorption and EPR) measurements were carried out. The results have been compared with the literature data accessible only for uracil and thymine. A deprotonation of the ML complexes in a more basic solution was indicated, thus, extending the coordination mode proposed up to now for uracil and thymine. An electron withdrawing effect of substituents has been found for 6-chloromethyluracil and diethyl 6-uracilmethylphosphonate.

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Reactivity of cis-Diaminedichloroplatinum(II) (cis-Platin) Toward Chromium(IV)

Stawińska J., Staszak Z., Jezierska J., Cieślak-Golonka M., Daszkiewicz M.

Polish Journal of Chemistry

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2000

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Vol. 74, nr 3

291-301

EN

The interaction of Cr(VI) compounds: K2Cr2O7 with cis-diaminedichlorplatinum(II) (cis-Platin) has been studied spectroscopically (UV-VIS, IR, FIR, ESR). It was found that the redox processes took place with the precipiation of brown Pt(IV)-Cr(III) heteropolynuclear products. The deconvolution of the electronic spectra allowed the analysis in convention of independent Pt(IV) and Cr(III) crystal fields.

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The role of the side group in reactions involving 1-propyl-2-methylimidazole and 1-propyl-2-imidazole-carboxaldehyde and Co(II), Ni(II), Cu(II) and Zn(II) ions

Barszcz B., Kulig J., Jezierska J., Lisowski J.

Polish Journal of Chemistry

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1999

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vol. 73 nr 3

447-456

EN

The complexing properties of 1-propyl-2-methylimidazole (1-Pr-2-CH3Im) and 1-propyl-2-imidazolecarboxaldehyde (1-Pr-2-CHOIm) with CoII, NiII, CuII and ZnII were investigated pH-metrically at 25oC and at the ionic strength of 0.5 mol dm-3(KNO3). The stability constans calculated indicate the formation of complexes with metal: ligand ratio of 1:1, 1:2, 1:3, and 1:4. The stability of the metal complexes with both imidazoles depends mostly on the substituent situated between the nitrogen atoms of the imidazole ring. It was found that the carboxalaldehyde oxygen atom participates in the formation of the coordination bond. The formation of the weak chelate copper (II)-1-propyl-2-imidazolecarboxaldehyde complexes was confirmed by EPR spectra. The electronic spectra reveal that the cobalt(II) forms both tetrahedral and octahedral species with 1-Pr-2-CH3Im, but 1_Pr-2-CHIIm forms only six-coordinated compounds. The NMR spectra of 1_Pr-2-CHOIm indicate that hydration of the CHO takes place when Zn(II) ions are introduced into the ligand solution at pH5.03.