PL ISSN 0137-5083
Synthesis and Spectral Studies on Mononuclear Copper(II) Complexes of Isonitrosoacetyl-acetone Ligand
Reduction Mechanisms of Co(II) Complexes with Diamino Acids and Histidine on the Dropping Mercury Electrode
Synthesis of Some New Pyrimidines
Assy M.G. and Moustafa H.Y.
2- and 2,7-Substituted Iodonium/Diiodonium Salts Derived from Xanthene, Xanth-9-one, Fluorene, and Fluoren-9-one
Farhan A.N., Skulski L. and Kryska A.
Synthesis and Properties of New 2-Alkyl-1,4-benzoxazepine Derivatives. Part II. Halogenated|
Kwiecien H. and Baumann E.
Isovellerol and New Isolactarane Sesquiterpenes, Their Structure and Antifeedant Activity
Daniewski W.M., Gumulka M., Bloszyk E., Jacobsson U. and Norin T.
Stability of Micelles in Aqueous Salt Solutions of Dodecylpyridinium Halides
Binary Monolayers of Functionalized Long-chained Amphiphiles
Kucharski S. and Janik R.
Kinetics of Consecutive Reactions Catalyzed by Decaying Catalysts
Marczewski M. and Marczewska H.
Adsorption of Some Normal Aliphatic Amines on Polycrystalline Gold Electrode
Brzostowska-Smolska M. and Krysinski P.
The Kinetics of 1-Chloro-2,3-epoxypropane Reaction with Alcohols and Their Adducts in the Presence of Boron Trifluoride
Chlebicki J. and Pozniak R.
Note on the Capillary Model of Transport through Charged Membranes
Hydrodechlorination of CF2Cl2 (CFC-12) on Pd/Al2O3 Catalysts
Juszczyk W., Malinowski A., Bonarowska M. and Karpinski Z.
Molecular Modelling of Three-Dimensional Structure of 1,25-Dihydroxycholecalciferol and Its A-Ring Analogs
Cholinski J. and Kutner A.
1H and 14N NMR Shielding Constants Differentiate Two Polymorphic Forms of Solid NH4NO3
Wielogorska E., Jackowski K. and Wozniak K.
Thermoelectric Characteristics of the CuCl2-HCl Electrochemical System with Copper Electrodes
Tevtul Ya. and Burkun N.
CRYSTAL AND MOLECULAR STRUCTURES
Crystal Structure and Phase Transitions of the Ferroelectric Antimony Sulfoiodide SbSI. Part I. Phase Diagram and Thermal Expansion of SbSI
Lukaszewicz K., Pietraszko A., Stepien-Damm J. and Kajokas A.
The Crystal Structures of Diaquobis(3-aminopyrazine-2-carboxylato-N,O)magnesium(II)monohydrate and 3-Aminopyrazine-2-carboxylic Acid
Ptasiewicz-Bak H. and Leciejewicz J.
Molecular Ribbons Composed of Calcium Atoms Bridged by Carboxylate Oxygens in the|
X-ray Structure of Calcium Complex with 3-Aminopyrazine-2-carboxylic Acid
Leciejewicz J., Ptasiewicz-Bak H. and Paluchowska B.
Synthesis and Properties of the Complexes of Gadolinium with Nitronyl Nitroxides
Qi Y.Q., Zou G.Z., Liao D.Z., Jiang Z.H. and Wang G.L.
Systemin - a Polipeptide Inducer of Proteinase Inhibitors Synthesis in Plants: Synthesis and Chemical Stability
Mucha P., Rekowski P., Szyk A., Kupryszewski G. and Barciszewski J.
Synthesis and Spectral Studies on Mononuclear Copper(II)
by A.S. El-Tabl
(Received November 13th, 1996; revised manuscript February 28th, 1997)
Reaction of isonitrosoacetylacetone (Hinaa) with CuX2.nH2O, (X = CH3CO2, Cl or NO3, n = 1, 2 or 3) led to complexes of types (inaa)2Cu.3H2O and (Hinaa)2CuX2.H2O, (X = Cl or NO3). The octahedral complexes have been postulated due to elemental analysis, IR, VIS-U.V spectra, magnetic susceptibility, conductivity and ESR spectra. Molar conductance of the complexes in DMF indicates non-ionic character. ESR spectrum of (inaa)2Cu.3H2O in CD3OD/D2O (10%) at 77 K shows axial type symmetry (dx2-y2). However, the spectrum of the solid (Hinaa)2CuCl2.H2O at room temperature with gperpend >> g|| >> 2.002 indicates a compressed tetragonal distortion along the Z-axis with the unpaired electron in dz2 orbital.
Reduction Mechanisms of Co(II) Complexes
by J. Urbanska
(Received February 10th, 1997; revised manuscript March 17th, 1997)
DC and DP polarography were used to study the reduction of Co(II) in the presence of potentially terdentate diamino acids (2,3-diaminopropionic acid, 2,4-diaminobutyric acid, histidine). The stoichiometry of the species discharging on a mercury electrode and the relevant electrochemical kinetic parameters were determined. The electrochemical behaviour of particular species strongly depends on the donor system bound to the metal ion.
Synthesis of Some New Pyrimidines
by M.G. Assy and H.Y. Moustafa
(Received November 14th, 1996; revised manuscript April 16th, 1997)
Chlorolysis of pyrimidinethione 1 yielded chloropyrimidine 3, which reacted with arylamines to yield 4-arylaminopyrimidines 4a-c. Compounds 4a,b were condensed with benzaldehyde to afford pyridopyrimidines 6a,b, which underwent cyclization to pyirmidoquinazoline 7. Compound 3 reacted with ethyl glycinate to give pyrrolopyrimidine 9. Chloropyrimidine 3 reacted with acid hydrazide to afford hydrazides 10a,b that underwent intramolecular cyclodehydration to triazolopryimidine 11. Synthesis of furopyrimidine 13, thienopyrimidine 14 and 4-ethoxypyrimidine 15 was also described.
2- and 2,7-Substituted Iodonium/Diiodonium Salts
by A.N. Farhan, L. Skulski and A. Kryska
(Received May 6th, 1997; revised manuscript June 5th, 1997)
Thirty three new 2- and 2,7-substituted iodonium/diiodonium salts derived from xanthene, xanth-9-one, fluorene, and fluoren-9-one are reported in this paper. Their structures were supported analytically and by their 1H NMR and IR interpreted spectra.
Synthesis and Properties of New 2-Alkyl-1,4-
by H. Kwiecien1 and E. Baumann2
(Received April 17th, 1997; revised manuscript June 9th, 1997)
Novel bromo and iodo substituted 2-alkyl-2,3,4,5-tetrahydro-1,4-benzoxazepine-3,5- -diones 5 have been prepared by cyclodehydratation of 2-(2-carbamoilphenoxy) alkanoic acids 4 and as the result of the reaction of halogenated salicylamides 1 with 2-bromo
Isovellerol and New Isolactarane Sesquiterpenes,
by W.M. Daniewski1, M. Gumulka1, E. Bloszyk2, U. Jacobsson3 and T. Norin3
(Received June 10th, 1997; revised manuscript June 23th, 1997)
High antifeedant activity of isovellerol, a gamma-hydroxy-aldehyde sesquiterpene of marasmane skeleton prompted us to synthesize the same type of compounds with the isolactarane skeleton, and to check their antifeedant activity. LiAlH4 reduction of isolactarorufin gave the desired compound, besides the tetraol (a compound with open lactone ring). Extensive spectroscopic investigation (including X-ray) indicated that the desired gamma-hydroxy-aldehyde in chloroform solution existed in the cyclic (lactol) form. Antifeedant activities of both compounds against the storage pests were moderate.
Stability of Micelles in Aqueous Salt Solutions
by R. Zielinski
(Received January 17th, 1997; revised manuscript March 13th, 1997)
Stability of spherical and rod-like micelles of cationic surfactants in aqueous salt solutions have been treated on the basis of a statistical thermodynamic theory, corrected by incorporation of the micellar surface energy term. The modified equations for the double logarithmic relationship between micellar aggregation number and ionic strength of the solution have been derived. The newly derived equations have been applied to aqueous sodium halides solutions of dodecylpyridinium halides including those of chloride, bromide and iodide. Effect of salt concentration on the degree of ionization and the energy of hydration of both spherical and rod-like micelles have been demonstrated. Degree of ionization of the micellar associates decreases with increasing salt concentration for all surfactants studied. Energy of hydration of both spherical and rod-like micelles is negative and it increases with increasing salt concentration.
Binary Monolayers of Functionalized
by S. Kucharski and R. Janik
(Received March 17th, 1997)
Monolayer films of binary systems were investigated with reference to miscibility of the components described in terms of excess surface area, Aexc, and excess free energy of mixing, DELTAGexc. The binary systems contained at least one component able to generate nonlinear optical effects or (and) to show semiconductive ability. The materials tested were: poly(n-octadecylthiophene), p-(1-n-octadecylpyrryl-2-azo)benzenesulfonic acid, (p-(1-n-octadecylpyrryl-2-azo)benzoic acid, and 2,4-dinitrophenylhydrazone of 3-n- -octadecanoylpyrrole. As film builders there were used 1-n-octadecylimidazole and 3-n-octadecylpyrrole. On the basis of surface excess area, Aexc, and surface excess free energy, DELTAGexc, the regions of positive synergic interactions between film components were determined.
Kinetics of Consecutive Reactions Catalyzed
by M. Marczewski and H. Marczewska
(Received March 13th, 1997; revised manuscript April 3rd, 1997)
The kinetics of complex catalytic reaction of A -> B -> C type proceeding in the presence of decaying catalyst in a batch reactor is discussed. Calculated model correlations between reactant conversions and reaction time/total conversion were used to analyze n-pentane transformation in the presence of solid superacid Al2O3-SbF5 catalyst.
Adsorption of Some Normal Aliphatic Amines
by M. Brzostowska-Smolska and P. Krysinski
(Received January 24th, 1997; revised manuscript April 10th, 1997)
The adsorption of n-octylamine, n-dodecylamine, n-hexadecylamine and n-octadecyl-amine on a polarized Au electrode from LiClO4 methanolic solutions has been studied by capacity measurements. Some adsorption parameters for the potential near to the potential of maximum adsorption have been calculated, according to Frumkin's and Damaskin's theory. A discussion of the results connected with the literature data concerning the adsorption of alcohol molecules has been provided.
The Kinetics of 1-Chloro-2,3-epoxypropane Reaction
by J. Chlebicki and R. Pozniak
(Received December 20th, 1996; revised manuscript April 11th, 1997)
Rate constants for the reaction of 1-chloro-2,3-epoxypropane with n-, sec-, tert-butyl, n-hexyl, n-octyl, and n-decyl alcohols in the presence of boron trifluoride were studied at 30, 40, and 50oC. The reaction rate is first order with respect to 1-chloro-2,3-epoxypropane and independent of alcohol concentration. The rate constant is proportional to the catalyst concentration. The rate constants increase in the homologous series of C4-C10 alcohols. The reaction rates of 1-chloro-2,3-epoxypropane with 1-alkoxy-3- -chloro-2-propanols are considerably larger than that with corresponding alcohols.
Note on the Capillary Model of Transport
by S. Koter
(Received January 17th, 1997; revised manuscript April 18th, 1997)
The capillary model of transport through charged membranes has been reformulated by transport equations of non-equilibrium thermodynamics. Two geometries of pores has been considered - a capillary and a slit. It has been assumed that the distribution of mobile components is governed by the zero components of forces in the plane perpendicular to the direction of transport. It has been shown that the part of transport coefficients, describing the motion of the center of mass, depends on the distribution of species inside the capillary and on the viscosity of the solution. The transport coefficients, averaged over the cross-section, are symmetrical.
Hydrodechlorination of CF2Cl2 (CFC-12)
by W. Juszczyk, A. Malinowski, M. Bonarowska and Z. Karpinski
(Received April 22nd, 1997)
The reaction of hydrodechlorination of CF2Cl2 was studied in the presence of similarly dispersed alumina-supported palladium catalysts. Catalytic activity of alpha-Al2O3- and gamma-Al2O3-supported palladium does not depend on the fact, which type of alumina was used as a support. However, palladium supported on alpha-Al2O3 appeared more selective towards CF2H2 than Pd/gamma-Al2O3. Since alpha-Al2O3 is markedly less porous carrier than gamma-Al2O3, lower selectivity towards partial hydrodehalogenation on Pd/gamma-Al2O3 may result from a consecutive reaction of CF2H2 to methane. High temperature pretreatment supposedly eliminates narrow pores in gamma-Al2O3, what, in consequence, leads to higher selectivity to CF2H2. Carbiding palladium surfaces takes place during the reaction. After carbon removal, Pd/Al2O3 shows a similar catalytic behaviour as fresh samples.
Molecular Modelling of Three-Dimensional
by J. Cholinski and A. Kutner
(Received February 12th, 1997; revised manuscript May 9th, 1997)
Two major force fields (Tripos and MMX) were used to calculate three dimensional structures, steric energies and Boltzmann distribution of low energy conformers of 1,25-dihydroxycholecalciferol and its A-ring analogs. Molecular modelling revealed that out of a series of analogs substituted at carbon atom C(4), (4R)-4-methyl-1,25-dihydroxycholecalciferol might be expected to exist in a solution preferentially in a ß-type of conformation of an A ring. This analog, compared to the (4S) isomer, is to be used for further structure - activity study of the ß-type conformation of an A-ring as a hypothetical active form in which vitamin D compound interacts with vitamin D receptor.
1H and 14N NMR Shielding Constants Differentiate
by E. Wielogorska, K. Jackowski and K. Wozniak
(Received May 20th, 1997)
The gauge-independent atomic orbital (GIAO) approach has been used within the coupled Hartree-Fock approximation to compute 1H and 14N NMR shielding constants in selected ion pairs of solid NH4NO3. Assuming additivity of intermolecular effects the shielding constants of NH4+ ions in two different polymorphic forms of ammonium nitrate have been determined. According to our calculations condensation of NH4NO3 leads to small deshielding effects for 1H and 14N nuclei. Geometry of the central NH4+ cation is the most important factor influencing results of calculations of nuclear shielding constants. This geometry reflects the role of intermolecular interactions in the crystal lattice. Our results show that the GIAO approach at the Hartree-Fock level differentiates two polymorphic forms of ammonium nitrate. Some results on temperature dependences for 1H and 14N shielding constants are included. There is a linear dependence between the 1H and 14N shielding constants.
Thermoelectric Characteristics of the CuCl2-HCL
by Ya. Tevtul and N. Burkun
(Received November 20th, 1996; revised manuscript May 23rd, 1997)
The non-isothermal system of copper electrodes in aqueous solution of CuCl2 + HCl has been studied. The interval of HCl concentrations with a linear dependence of non-isothermal electromotive force (emf) on the temperature difference has been determined. Thermoelectric potentials and phenomenological coefficients have been evaluated. The contribution of particle fluxes caused by temperature gradient to the total flux of charged particles is estimated to 15-20%.
Crystal Structure and Phase Transitions
by K. Lukaszewicz1, A. Pietraszko1, J. Stepien-Damm1 and A. Kajokas2
(Received February 3rd, 1997; revised manuscript March 21st, 1997)
Precise lattice parameters of antimony sulfoiodide SbSI single crystals have been determined by the Bond method between 95-460 K. Apart from the ferroelectric phase transition at 298 K, a high temperature phase transition was found at 410 K. In the ferroelectric phase the lattice parameter c increases with decreasing temperature and reaches the maximum value at about 150 K. There is also a small anomaly of the temperature dependence of lattice parameter a, which increases below the Curie point, reaches the maximum value at 290 K and decreases at lower temperatures. No anomalies of thermal expansion were observed between 210-260 K, where a low temperature phase transition was reported by some authors.
The Crystal Structures of Diaquobis(3-aminopyrazine-2-
by H. Ptasiewicz-Bak and J. Leciejewicz
(Received February 4th, 1997; revised manuscript April 29th, 1997)
Diaquobis(3-aminopyrazine-2-carboxylato-N,O)magnesium(II)monohydrate, MgC10H14N6O7 crystallizes in the monoclinic system, space group Cc. Lattice parameters: a = 12.225(5), b = 8.286(1), c = 15.964(2) Å, ß= 112.50(3) deg., Z = 4. The structure is composed of monomeric molecules. The Mg+2 ion is coordinated by two acid molecules and two water molecules. The coordination octahedron of the Mg+2 ion consists of two heteroring nitrogens (Mg-N = 2.255 Å) and two oxygen atoms belonging to two monodentate carboxylic groups (Mg-O = 2.070 Å) donated by two acid molecules plus two oxygen atoms of water molecules (Mg-O = 2.040 Å). A network of hydrogen bonds is operative between the monomers and solvation water molecules.
Molecular Ribbons Composed of Calcium Atoms
by J. Leciejewicz1, H. Ptasiewicz-Bak 1 and B. Paluchowska2
(Received April 10th, 1997; revised manuscript May 8th, 1997)
The crystals of monoaquabis(miu-3-amino-2-pyrazinato)calcium(II) are monoclinic, space group Cc, a = 22.787(5), b = 6.367(1), c = 9.906(2) Å, ß = 110.58(3) deg., Z = 4. Each calcium atom is coordinated by two aminopyrazinate molecules via their heteroring nitrogens (Ca-N = 2.594 Å ) and the nearest to them two oxygens of the carboxylate groups (Ca-O = 2.385 Å) and by one water molecule with Ca-O = 2.344 Å, making with aminopyrazinate ligands a planar "step". Two other oxygen atoms are chelated to the calcium atom, each contributed by the second oxygen atom of the carboxylic group situated in the "step" above and below (mean Ca-O = 2.363 Å). The carboxylic groups are bidentate and bridge the "steps" into ribbons propagating along the c axis. The ribbons are linked by strong hydrogen bonds of 2.71(1) and 2.74(1) Å operating between the coordinated water oxygen and the carboxylic oxygens in the adjacent ribbons.
Synthesis and Properties of the Complexes
by Y.Q. Qi, G.Z. Zou, D.Z. Liao, Z.H. Jiang and G.L. Wang
(Received January 27th, 1997; revised manuscript April 9th, 1997)
Systemin - a Polipeptide Inducer of Proteinase
by P. Mucha1, P. Rekowski1, A. Szyk1, G. Kupryszewski1 and J. Barciszewski2
(Received May 9th, 1997; revised manuscript June 9th, 1997)
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© 1997 Polish Journal of Chemistry
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