Download Abstracts

Survey
yes no Was this document useful for you?
   Thank you for your participation!

* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project

Document related concepts
no text concepts found
Transcript
Polish J. Chem., 76, 1053–1084 (2002)
REVIEW ARTICLE
Palladium Complexes in Carbohydrate Synthesis
by A. Zamojski
Institute of Organic Chemistry, Polish Academy of Sciences,
ul. Kasprzaka 44/52, 01-224 Warsaw, Poland
(Received April 22nd, 2002)
The survey reports the results achieved in carbohydrate synthesis by application of
organopalladium complexes. Most remarkable results have been noted in C-glycoside
synthesis and in the chemistry of unsaturated sugars. In the majority of cases high
regio- and stereoselectivity of transformations is observed. Many palladium catalysts
with different organic ligands have been employed. The literature up to the end of 2001 is
reviewed.
Polish J. Chem., 76, 1085–1094 (2002)
INORGANIC CHEMISTRY
Synthesis, Structural Characterization, Redox and
Antimicrobial Studies of Schiff Base Copper(II),
Nickel(II), Cobalt(II), Manganese(II), Zinc(II) and
Oxovanadium(II) Complexes Derived from Benzil and
2-Aminobenzyl Alcohol
by N. Raman1, A. Kulandaisamy1 and K. Jeyasubramanian2
2
1
Department of Chemistry, VHNSN College, Virudhunagar 626 001, India
Department of Chemistry, Mepco Schlenk Engineering College, Sivakasi 626 005 , India
(Received March 4th, 2002; revised manuscript May 13th, 2002)
Neutral complexes of Cu(II), Ni(II), Co(II), Mn(II), VO(II) and Zn(II) have been synthesized from the Schiff base derived from benzil and 2-aminobenzyl alcohol. The structural features have been arrived from their microanalytical, IR, UV-Vis, 1H NMR, Mass
and ESR spectral data. All of the complexes exhibit square-planar geometry except the
Mn(II) and VO(II) complexes. The Mn(II) chelate shows an octahedral environment
and the VO(II) chelate exists in a square-pyramidal geometry. The monomeric and
non-electrolytic nature of the complexes is evidenced by their magnetic susceptibility
and low conductance data. The cyclic voltammogram of copper complex in acetonitrile
solution shows two quasi reversible peaks for the Cu(II)/Cu(III) and Cu(II)/Cu(I) couples.
The X-band ESR spectra of the Cu(II) and VO(II) complexes in DMSO at 300 and 77 K
were recorded and their salient features are reported. The biological activity of the
metal chelates against the bacteria Staphylococcus aureus, Bacillus subtilis, Klebsiella
pneumoniae, Salmonella typhi, Pseudomonas aeruginosa and Shigella flexneri are
also reported. Most of the complexes have higher activity than that of the free Schiff base
and the control.
Polish J. Chem., 76, 1095– (2002)
Phase Equilibria in the System CePO4 – Ba3(PO4)2
by W. Szuszkiewicz, E. Radomiñska, T. Znamierowska and P. Wilk
Department of Inorganic Chemistry, Faculty of Engineering and Economics,
Wroc³aw University of Economics, Komandorska 118/120, 53-345 Wroc³aw, Poland
(Received April 25th, 2002)
Based on thermal investigation and X-ray powder diffraction the unknown so far phase
diagram of the binary system CePO4–Ba3(PO4)2 has been elaborated. It contains an intermediate compound Ba3Ce(PO4)3, which congruently melts at about 2080°C, is stable
down to room temperature and has an eulytite structure. In the composition range given
by the molar ratio of CePO4:Ba3(PO4)2 from 1:1 to 1:6 there exist solid solutions of the
eulytite structure. At high temperatures there exist two binary eutectics (te1 = 1840°C,
te2 = 1600°C).
Polish J. Chem., 76, 1104–1100 (2002)
The System LaPO4 – Ca3(PO4)2 – Ca2P2O7
by W. Jungowska
Department of Inorganic Chemistry, Faculty of Engineering and Economics,
Wroc³aw University of Economics, Komandorska 118/120, 53-345 Wroc³aw, Poland
(Received April 29th, 2002; revised manuscript June 7th, 2002)
The phase diagram of the ternary system LaPO4 – Ca3(PO4)2 – Ca2P2O7 has been determined by thermal, X–ray and microscopic examinations. The system contains only one
double phosphate Ca3La(PO4)3 which is formed at the 1:1 molar ratio LaPO4:Ca3(PO4)2.
Polish J. Chem., 76, 1105–1111 (2002)
ORGANIC CHEMISTRY
Application of Silicon-Phosphorus Based Reagents
in Synthesis of Aminophosphonates. Part 2:
Reactions of N-(Triphenylmethyl)-aldimines
with the Silylated Phosphorus Acid Esters
by B. Boduszek and M. Soroka
Institute of Organic Chemistry, Biochemistry and Biotechnology,
Wroc³aw University of Technology, 50-370 Wroc³aw, Poland
(Received December 27th, 2001; revised manuscript May 6th, 2002)
Reactions of silylated phosphorus acid esters with N-triphenylmethylaldimines (N-tritylaldimines) were investigated. N-Tritylmethaneimine reacts at room temperature with
a mixture of P(OMe)3 and Me3SiBr forming the corresponding aminophosphonate derivatives in high yield. Other N-tritylimines are resistant toward the silylated reagents at
room temperature, but undergo a similar phosphonylation reaction at elevated temperatures to form the expected aminophosphonic acids.
Polish J. Chem., 76, 1113–1125 (2002)
Structure and Rearrangement of Ring Substituted
N-Methyl-N-phenylnitramines
by Z. Daszkiewicz, J. Zaleski, E.M. Nowakowska and J.B. Kyzio³
Institute of Chemistry, University of Opole, 45-052 Opole, ul. Oleska 48, Poland
(Received February 15th, 2002; revised manuscript May 6th, 2002)
The mechanism of the acid catalyzed nitramine rearrangement must account for the unusual sensitivity of the reaction of N-methyl-N-phenylnitramine derivatives to the ring
substituents. Spectral analyses indicate the lack of interaction between the nitramino
group and the second substituent through the aromatic ring. X-ray analyses confirm the
spectral data: there is no conjugation between the aromatic and nitramine sextets of
p-electrons. X-ray structural data also indicate that the nitramino group cannot behave as
the basic centre. A reconsideration of the rearrangement rate constants of the series of
ring substituted N-methyl-N-phenylnitramines lead to the conclusion that migration of
the N-nitro group precedes protonation. The influence of the substituents on the reaction
rates is determined by their influence on the basicity of the imino nitrogen in an intermediate. The CIDNP effect, observed in the rearrangement, results from the transformation
of mobile nitrito group into the stable nitro substituent.
Polish J. Chem., 76, 1127–1136 (2002)
1
H, 13C and 15N NMR Study of Nitrosoureido Sugars,
Derivatives of 2-Amino-2-deoxy-b-D-glucopyranoside
and Amino Acids or Peptides
by I. Wawer1, M. Weychert1, B. Piekarska-Bartoszewicz2 and A. Temeriusz2
1
Faculty of Pharmacy, Medical University of Warsaw, Banacha 1, 02097 Warsaw, Poland
E-mail: [email protected]
2
Department of Chemistry, Warsaw University, Pasteura 1, 02093 Warsaw, Poland
E-mail: [email protected]
(Received January 28th, 2002; revised manuscript June 3rd, 2002)
Nitrosoureido sugars with amino acid and dipeptide ester residue were characterized by
1
H, 13C and 15N NMR and their spectra were assigned using 1D and 2D NMR methods.
The N-nitrosation of ureido sugars frequently yields a mixture of isomers. In the case of
ureido sugars with amino acid residues preferably the N3–NO isomers were obtained,
whereas for compounds with dipeptide esters the N1–NO isomers dominate. The results
are in agreement with the molecular modelling (PM3) predictions, when the intramolecular hydrogen bonds, net charges at nitrogen atoms and heat of formations of particular
isomers are considered.
Polish J. Chem., 76, 1137–1142 (2002)
Reaction of N-Arylbenzamidines
with Arenenitrile N-Oxides
by W. Szczepankiewicz1, T. Borowiak2, M. Kubicki2,
J. Suwiñski1 and P. Wagner1
1
Institute of Organic Chemistry and Technology, Silesian University of Technology,
Krzywoustego 4, 44-100 Gliwice, Poland;
E-mail: [email protected]
2
Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60-780 Poznañ, Poland
(Received April 8th, 2002; revised manuscript June 10th, 2002)
Looking for a method of 4-arylamino-4-aryl-3-aza-3-buten-2-one oximes preparation a
reaction of N-arylbenzamidines with arenenitrile N-oxides (generated in situ form oximoyl
chlorides) has been performed to produce unstable 5-amino-4,5-dihydro-1,2,4-oxadiazoles,
which under aqueous acidic conditions hydrolyzed to acyclic N-benzoyloxy-N’-arylareneamidines. Structure of one of the latter compounds has been confirmed by X-ray
analysis.
Polish J. Chem., 76, 1143–1150 (2002)
PHYSICAL CHEMISTRY
A Study on a Phase Transition in Electrodeposited Thin
Film Polyaniline Using AC Conductivity Measurements
by M. Grzeszczuk and G. Bator
Faculty of Chemistry, University of Wroc³aw,
F. Joliot-Curie 14 str., 50-383 Wroc³aw, Poland
(Received March 11th, 2002)
Ac conductivity – temperature dependencies of Au/polyaniline/Au structures with the
electrodeposited thin film polyaniline are presented. The data for the reduced and reversibly oxidized polymer samples of estimated thickness being in 10–1–100 µm range are
shown. The charge transport laws are found similar to that observed for the chemically
prepared conducting polymer. The observed crossover in the conductivity – temperature
dependence coincides with the increase in the electrical capacitance of the polyaniline
electrode reported earlier.
Polish J. Chem., 76, 1151–1162 (2002)
Surface-Enhanced Raman Spectroscopy and
Electrochemical Studies of 4-Phenylpyridine
Adsorption at the Silver/Solution Interface
by J. Bukowska, M. Calvo, M. Jurkiewicz-Herbich and K. Jackowska
Department of Chemistry, Warsaw University, ul. Pasteura 1, 02-093 Warsaw, Poland
(Received March 20th, 2002)
The adsorption of 4-phenylpyridine (4-PhPy) on silver was examined using conventional
electrochemical techniques: cyclic voltammetry, impedance measurements and surface
enhanced Raman spectroscopy (SERS) in a wide range of electrode potentials. Electrochemical results indicate a weaker adsorption of 4-PhPy molecules on Ag than on Au
electrode, but considerably stronger than adsorption of pyridine. For saturated solutions
the Raman results point out the reorientation of the 4-PhPy molecules from more flat configuration at potentials more positive than –0.7 V vs SCE, to more perpendicular one at
more negative potentials. This reorientation may be connected with the formation of stable surface complexes at potentials more positive than –0.7 V and of molecular stacks at
more negative electrode potentials.
Polish J. Chem., 76, 1163–1173 (2002)
The Enthalpy of Formation of Cubic Boron Nitride
by I. Tomaszkiewicz
Chemical and Physical Properties Division, National Institute of Standards
and Technology, Gaithersburg, Maryland 20899, U.S.A. and
Institute of Physical Chemistry of the Polish Academy of Sciences,
Kasprzaka 44, 01-224 Warsaw, Poland; e-mail: [email protected]
(Received April 25th, 2002)
The massic energies of combustion in fluorine of two specimens of cubic boron nitride
have been measured in a bomb calorimeter, the standard molar enthalpy of formation
D f H0m (c-BN, cr, 298.15 K) = –254.6±1.5 and the enthalpy of polymorphic transition
D trs Hm0 (298.15 K) = –3.5±1.5 of the process: h-BN (cr) ® c-BN (cr) have been determined. Those quantities are compared with the values determined previously.