JSCS Vol 63, No. 12
J. Serb. Chem. Soc. 63(12) 903-908 (1998)
UDC 547.924:542.91
JSCS-2599
Original scientific paper
Partial synthesis of
14a-hydroxy-5a-cholestan-3b-yl acetate
MIRA BJELAKOVIC*, VLADIMIR PAVLOVIC*,**, LJUBINKA LORENC*,** and
MIHAILO LJ. MIHAILOVIC*,**
*Center for Chemistry, ICTM,
P.O.Box 815, YU-11001 Belgrade, and
**Faculty of Chemistry, University of Belgrade, Studentski trg
12-16, P.O.Box 158, YU-11001 Belgrade, Yugoslavia
(Received
10 September 1998)
A
convenient synthesis (in seven steps) of the 14a-hydroxy-5a-cholestan-3b-yl
acetate (8, Scheme 2) is described. The synthesis starts from
cholesteryl acetate (1) and involves the following transformations: (i)
bromination/dehydrobromination of cholesteryl acetate (1); (ii)
partial hydrogenation of the D5-bond in
the obtained 7-dehydrocholesteryl acetate (2); (iii) migration of
the D7-double bond in the thus formed compound 3 to the D8(14)-position;
(iv) isomerisation of the D8(14)-unsaturated
product 4 to the D14-analogue 5 (v)
epoxidation of the D14-bond in 5; (vi) lithium aluminium hydride reduction
of the 14a-,15a-epoxide 6; and (vii) partial acetylation of the
3b-hydroxyl function in the obtained diol 7 producing the final product 8.
The total yield of the synthesis is ca. 18%.
Key
words: 7-dehydrocholesteryl acetate, partial hydrogenation, D7-bond
migration, 14a,15a--epoxy-5a-cholestan-3b-yl acetate,
14a-hydroxy-5a-cholestan-3b-yl acetate.
J. Serb. Chem. Soc. 63(12) 909-913 (1998)
UDC 547.8:542.91:547.391.1
JSCS-2600
Original scientific paper
Synthesis of heterocyclic compounds
from the amination products of 3-(4-phenyl benzoyl)acrylic acid
A. Y. SOLIMAN and I. A. ATTIA*
Chemistry Department, Faculty of
Science at Fayoum, Cairo University, Fayoum, Egypt, and
*Chemistry Department, Faculty of Engineering, Ain Shams
University, Cairo, Egypt
(Received
17 November 1997)
Amination
of 3-(4-phenylbenzoyl)acrylic acid gave 2N-(arylamino)-3-(4'-phenylbenzoyl)propionic
acids 2, the hydrazinolysis of which yielded the corresponding
6-(4-biphenylyl)-4-(N-arylamino)-2,3,4,5-tetrahydro pyridazin-3-ones 3.
These latter com-pounds were also prepared by the hydrazinolysis of Db,g
- butenolides, which were obtained from the dehydration of 2. The lactam
= lactim dynamic equilibrium of 3 was chemically investigated.
Key
words: heterocyclic compounds, amination of acrylic acid derivatives,
hydrazinolysis.
J. Serb. Chem .Soc. 93(12) 915-920 (1998)
UDC 547.836.3
JSCS-2601
Original scientific paper
A convenient preparation of
3-substituted-2-N-phenylamino-4(1H, 3H)-quinazolones
IBRAHIM M. EL-DEEN
Faculty of Education, Suez Canal
University, Port-Said, Egypt
(Received
24 June 1998)
Cyclization
of 2-(3-phenylthioureido)-benzoic acid (1) with acetic anhydride to give
2-N-phenylamino-4H-3,1-benzothiazin-4-one (3), followed by
the condensation of 3 with different amines results in 3-substituted-2-N-phenylamino-4(1H,
3H)-quinazolones.
Key
words: cyclization, 3,1-benzothiazinone, 3-substituted quinazolones.
J.
Serb. Chem. Soc. 63(12) 921-930 (1998)
UDC 547.787
JSCS-2602
Original scientific paper
Chiral oxazolines in 1,3-dipolar
cycloaddition reactions of azomethine ylides
SUREN HUSINEC and VLADIMIR SAVIC*
Institute of Chemistry, Technology
and Metallurgy, Center for Chemistry, Njegoseva 12, P.O.Box 815, YU-11000
Belgrade and
*Faculty of Pharmacy, Department of Organic Chemistry, Vojvode
Stepe 450, YU-11000 Belgrade, Yugoslavia
(Received
22 May, revised 24 September 1998)
Chiral
oxazolines have been used as chiral auxiliaries in cycloaddition reactions of
azomethine ylides generated from imines. Although cycloadducts were isolated in
good yields, the stereoselectivity varied depending on the auxiliary structure.
It has been demonstrated that a careful choice of the oxazoline auxiliary and
the dipolarophile could lead to a high diastereoselectivity.
Key
words: oxazolines, azomethine ylides, cycloadditions.
J.
Serb. Chem. Soc. 63(12) 931-939 (1998)
UDC 547.435.2/.3:547.572.3
JSCS-2603
Original scientific paper
Synthesis and reactivity of some
Mannich bases,
V.
Arylamine N-alkylation with Mannich bases derived from
2-hydroxy-5-methylacetophenone
GHEORGHE ROMAN, EUGENIA COMANITA*, BOGDAN COMANITA** and CAMELIA
DRAGHICI
Chemistry Department,
"Transilvania" University, 29 Eroilor Blvd., RO-2200 Brasov, Romania,
*Department of Organic Chemistry, "Gheorghe Asachi"
Technical University, 71A D. Mangeron Blvd., RO-6600 Iasi, Romania and
**Department of Organic Chemistry, University of Ottawa, 32
George Glinski, K1N 6N5 Ottawa, Canada
(Received 17 July 1998)
This paper presents the synthesis of a series of
arylamine Mannich bases derived from 2-hydroxy-5-methylacetophenone by means of
an amine-exchange reaction between 3-(dimethylamino)-1-(2'-hydroxy-5'-methylphenyl)propan-1-one
and variously substituted arylamines in an ethanol-water mixture. The reaction
proceeds smoothly and offers access with good yields to the desired products,
thus proving the applicability of this indirect method of arylaminomethylation
in the case of ortho-hydroxyacetophenones. The structures of the newly
prepared substances were ascertained by elemental analysis, IR, 1H-
and 13C-NMR, as well as mass spectroscopy.
Key
words: Mannich bases, amine-exchange reaction, arylamines,
barylaminoketones, ortho-hydroxyacetophenones.
J.
Serb. Chem. Soc. 63(12) 941-953 (1998)
UDC 623.459.46:623.459.8
JSCS-2604
Original scientific paper
The decomposition kinetics of some
contaminants in a mixture of sodium-2-methoxyethoxide and diethylenetriamine in
2-methoxyethanol
ZORAN LUKOVIC, NIKOLA BOCVAROV, BRATISLAV JOVANOVIC,* SNEZANA
RADOVANOVIC-SJAUS and MLADjEN MICEVIC**
Military Technical Institute of the
Yugoslav Army, Kataniceva 15, YU-11000 Belgrade,
*Faculty of Technology and Metallurgy, Karnegijeva 4, YU-11000
Belgrade and
**Institute of Disinfection, Desinsection and Deratisation,
Zarkovacka 14, YU-11000 Belgrade, Yugoslavia
(Received
10 July 1998)
The
results of the degradation kinetics of a fluorophosphonate (soman) and a
thiophosponate (VX), as well as of an analogue of N-yperite, with sodium
2-methoxyethoxide with or without diethylenetriamine (DETA) in 2-methoxyethanol
as a solvent are presented in this paper. The kinetic parameters of the denoted
reactions were calculated on the basis of the experimental data. For
comparison, the kinetic parameters obtained for the degradation of S-yperite,
using the same reagents were discussed.
Key
words: chemical warfare agents, decontamination, decontamination solution,
alkoxide, amine, mixtures of alkoxides and amines.
J. Serb. Chem. Soc. 63(12) 955-959 (1998)
UDC 547.92/ .924
JSCS-2605
Short communicaiton
SHORT COMMUNICATION
An
improved approach to B-norsteroids: An one-pot preparation of 3b-acetoxy-5-oxo-5,6-seco-cholestan-6-oic
and 3b-acetoxy-5,17-dioxo-5,6-seco-androstan-6-oic acids
LJUBOMIR S. STEVOVIC*, VLADIMIR D. PAVLOVIC*.** SASA B.
MARTINOVIC**, MILAN M. DABOVIC**, and IVAN O. JURANIC*,**
*Faculty of Chemistry, University
of Belgrade, Studentski trg 12-16, YU-11000 Belgrade and
**Center for Chemistry, Institute of Chemistry, Technology and
Metallurgy, Njegoseva 12,
YU-11000 Belgrade, Yugoslavia
(Received 10 August
1998)
A simple one-pot procedure for the synthesis of
the 5,6-seco-steroidal acids 9a,b in described in this paper. It
consists of the epoxidation of the D5-steroids, i.e.,
cholesteryl acetate (8a) and 17-oxo-aandrost-5-en-3b-yl acetate (8b)
with peracetic acid (generated in situ by the H2WO4/H2O2 system), followed by the CrO3/H2SO4 oxidation of the thus formed epoxides. The
5,6-seco-steroidal acids 9a,b (obtained in about 90% and 77% yield,
respectively) are transformed to the corresponding B-norsteroids by the known
method (Beayer-Villiger oxidation and subsequent thermolysis of the respective
blactones).
Key
words: D5-steroids, oxidation, 3b-acetoxy
-5-oxo-5,6-secocholestan-6-oic acid, 3b-acetoxy-5,17-dioxo-5,6-secoandrostan-6-oic
acid, B-norsteroids.
J.
Serb. Chem. Soc. 63(12) 961-966 (1998)
UDC 678.84
JSCS-2606
Original scientific paper
Short-range interaction parameters
for polydimethylsiloxanes with different terminal groups
GABRIELA GRIGORESCU, SILVIA IOAN, MARIANA PINTEALA and BOGDAN C.
SIMIONESCU
"P. Poni" Institute of
Macromolecular Chemistry, Iasi 6600 Romania and
*"Gh Asachi" Technical University, Department of
Macromolecules, Iasi 6600, Romania
(Received 4 Avgust 1998)
This paper discusses the influence of different
terminal groups on the conformation of polydimethylsiloxanes in dilute
solutions. The steric factor, which reflects the flexibility in the unperturbed
state, shows that the introduction of different end groups results in the
chains becoming less flexible as compared to polydimethylsiloxanes.
Key
words: polymer solution, polysiloxanes, flexibility.
J. Serb. Chem. Soc. 63(12 )967-977 (1998)
UDC 547.821.2:541.428.49/546.56 72'73''74'''
JSCS-2607
Original scientific paper
Transition metal complexes with
thiosemicarbazide-based ligands.
Part
36. Complexes of iron(III), nickel(II), cobalt(II) and copper(II)
with
2-acetylpyridine S-methylisothiosemicarbazone
VALERIJA I. CESLJEVIC, VUKADIN M. LEOVAC, PETAR N.
RADIVOJSA*, BRANISLAVA GORDIC** and GYULA ARGAY***
Institute of Chemistry, Faculty of
Sciences, University of Novi Sad, Trg D. Obradovica 3, YU-21000 Novi Sad,
Yugoslavia,
*Faculty of Chemistry, University of Belgrade, P.O. Box 158,
YU-11001 Belgrade, Yugoslavia,
**Faculty of Technology, University of Novi Sad, Bul. Cara Lazara
1, Yugoslavia and
***Central Research Institute for Chemistry, Hungarian Academy of
Sciences, P.O.Box 17, Budapest 114, H-1525, Hungary
(Received 25 May,
revised 3 September 1998)
The reaction of ethanolic solutions of
2-acetylpyridine S-methylisothiosemicarbazone with different salts of iron(II,
III), nickel(II), cobalt(II), and copper(II) gave mono(ligand), and in the case
of iron and nickel also bis(ligand) complexes of different compositions, in
which the ligand is coordinated either in the neutral, monoanionic, or mixed
form. A bidentate coordination of the neutral and a tridentate coordination of
the monoanionic form were postulated. The molar conductivities and IR spectra
indicate that, in addition to the organic ligand, the acid anions are in some
cases involved in the coordination. The bis(ligand) complexes have an
octahedral geometry, whereas for the mono(ligand) complexes a tetra- or
penta-coordination is supposed. Magnetic measurements showed that the title
ligand, even in the presence of iodide, can stabilize the higher oxidation
states of iron and copper.
Key
words: complex, iron(III), nickel(II), cobalt(II), copper(II),
2-acetylpyridine S-methylisothiosemicarbazone.
J. Serb.
Chem. Soc. 63(12) 979-985 (1998)
UDC 547.442.3:541.428.49/546.73/
JSCS-2608
Original scientific paper
Synthesis and physicochemical
characterization of the complex cis-[Co(acac)cyclam](ClO4)2
SOFIJA P. SOVILJ, KSENIJA BABIC-SAMARDZIJA and DRAGICA M. MINIC*
Faculty of Chemistry, University of
Belgrade, P.O. Box 158, YU-11001 Belgrade and
*Faculty of Physical Chemistry, University of Belgrade, P.O. Box
137, YU-11001 Belgrade, Yugoslavia
(Received 11 June,
revised 8 September 1998)
A new cobalt(III) complex cis-[Co(acac)cyclam](ClO4)2 (cyclam =
1,4,8,11-tetraazacyclotetradecane, acac = 2,4-pentanedione ion) has been
synthesized and characterized by elemental analysis, IR, electronic, 1H- and 13C-NMR and mass spectroscopy. Thermal decomposition
studies were also performed and the thermal stability region determined. The
spectroscopic data are consistent with a folded conformation of the macrocycle
around the cobalt atom, which is hexa-coordinated in a distorted octahedral
arrangement. The acac ion joins symmetrically through both the oxygen
atoms, the two remaining sites at the cobalt atom acting as a bidentate ligand.
Key
words: cobalt(III), cyclam, acetylacetonate, synthesis, complexes.
J. Serb. Chem. Soc. 63(12) 987-993 (1998)
UDC 547.538:54.022:541.124
JSCS-2609
Original scientific paper
Topologically activated sites in
benzenoid hydrocarbons. Polyacenes and benzo-annelated polyacenes
IVAN GUTMAN
Faculty of Science, University of
Kragujevac, P.O.Box 60, YU-34000 Kragujevac, Yugoslavia
(Received 24 August
1998)
If the interruption of conjugation at a pair of
carbon atoms of a benzenoid hydrocarbon, in the para position to each
other, increases the Kekul‚ structure count, then these sites are said to be
topologically activated. Oxidation, Diels-Alder addition, etc. usually occur at
topologically activated sites. The rules determining the existence and location
of toplogically activated sites in polyacenes and benzo-annelated polyacenes
are established.
Key
words: benzenoid hydrocarbons, Kekulé‚ structures, reactivity.
J.
Serb. Chem. Soc. 63(12) 995-1000 (1998)
UDC 541.183:661.65:546.57/541.182/
JSCS-2610
Original scientific paper
Adsorption of boron containing
molecules on silver nanoparticles
VESNA V. VODNIK and JOVAN M. NEDELJKOVIC
Vinca Institute of Nuclear
Sciences, P.O. Box 522, YU-11001 Belgrade, Yugoslavia
(Received 18 April,
revised 2 September 1998)
The effects of adsorption of boron containing
molecules on the optical properties and reactivity of colloidal silver
particles (4 nm diameter) were studied. The absorption spectra of silver
particles surface modified by tetraalkoxyborones are significantly different
from that of the primary silver sol. A decrease and broadening of the surface
plasmon absorption band are accompanied with the formation of a distinct long-wavelength
absorption band. The Fermi potential of silver particles complexed on their
surface by tetraethoxyborone is shifted towards a negative potential, and lies
between -0.2 and + 0.153 V.
Key
words: silver sol, surface modification, tetraalkoxyborones, Fermi level.
J. Serb. Chem. Soc. 63(12) 1001-1009 (1998)
UDC 547.263/.264:532.13:53.096
JSCS-2611
Original scientific paper
Viscosities and excess molar
volumes of binary liquid mixtures containing aliphatic alcohols at several
temperatures
MILAN SOVILJ and JASMINA JAKONIC
Department of Chemical Engineering,
Faculty of Technology, University of Novi Sad, YU-21000 Novi Sad, Yugoslavia
(Received
28 February, revised 22 September 1998)
Experimental
viscosities and excess molar volumes are presented for three binary liquid
mixtures containing aliphatic alcohols at 20, 25, 30 and 35 °C and atmospheric
pressure. The mixtures investigated were 2-propanol + 2-butanol, chloroform +
2-butanol, and chloroform + 2-propanol. The new viscosity data were fitted to
the Redlich-Kister equation to estimate the binary parameters and standard
deviations. The derived excess molar volumes were also correlated using the
Redlich-Kister equation.
Key
words: viscosity, excess molar volume, binary mixture, aliphatic alcohols.
J. Serb. Chem. Soc. 63(12) 1011-1017 (1998)
UDC 546.273-325:546.171.1
JSCS-2612
Original scientific paper
Thermodynamic consideration of the plasma
process for boron nitride powder production from boric acid
ZIVOTA G. KOSTIC, PREDRAG LJ. STEFANOVIC, PAVLE B. PAVLOVIC,
SLOBODAN Dj. SIKMANOVIC and DEJAN B. CVETINOVIC
The Vinca Institute of Nuclear
Sicences, Laboratory for Thermal Engineering and Energy, P.O. Box 522, YU-11001
Belgrade, Yugoslavia
(Received
15 May 1998)
The
results of equilibrium composition and total enthalpy computation in the
temperature range of 1000 to 6000 K and at pressure of 1 bar, for the systems
B-O-H-N and B-O-C-H-N are presented in this paper. These data enable the
determination, and optimization of mass, temperature and energy parameters of
the process for the production of ultrafine boron nitride powder by the
decomposition of boric acid in a nitrogen plasma, followed by reactive
quenching with cold methane.
Key
words: boron nitride, ceramic powder, plasma synthesis.
J.
Serb. Chem. Soc. 63(12) 1019-1030 (1998)
UDC 661.872.2:553.532
JSCS-2613
Original scientific paper
Influence of the iron oxidation
state on the nucleation of basalt glass
MIHAJLO B. TOSIC, RADOVAN Z. DIMITRIJEVIC*, SLOBODAN A.
RADOSAVLJEVIC and MIRJANA A. DjURICIC
Institute for the Technology of
Nuclear and Other Mineral Raw Materials, Franche d'Epere 86, YU-11000 Belgrade
and
*Faculty of Mining and Geology, University of Belgrade, Djusina 7,
YU-11000 Belgrade, Yugoslavia
(Received 10 December
1997, revised 3 September 1998)
The influence of the FeO/(FeO+Fe2O3) ratio on the nucleation of basalt glass was
investigated. In the studied glasses, this ratio was 0.69 and 0.995. It was
shown that at the ratio of 0.995 nucleation temperature was lower by 5°C, the
nucleation rate was lower by 13.4%, the crystallization activation energy was
higher by 94 kJ/mol and the nucleation curve was narrower. Heterogeneous
nucleation occurs in the investigated glasses. The same crystalline phase,
monoclinic pyroxene-augite (Ca, Mg, Fe, Al)(Si,Al)2O6 was developed during the
controlled crystallization of glasses A and B.
Key
words: glass, nucleation, iron effects.
J.
Serb. Chem. Soc. 63(12) 1031-1047 (1998)
UDC 547.261:541.138.2
JSCS-2614
Original scientific paper
The role of OHad species in
the methanol oxidation on low-index planes of platinum in alkaline solution
A. V. TRIPKOVIC, K. Dj. POPOVIC and D. M. DRAZIC
ICTM-Institute of Electrochemistry,
University of Belgrade, P.O.Box 815, YU-11001 Belgrade, Yugoslavia
(Received
9 October 1998)
The
oxidation of methanol was studied on the low-index planes of platinum in sodium
hydroxide solution, from the viewpoint of the influence of OHad species.
The OHad species originate during the reversible process of OH ion
electrosorption. The existence of some other kinds of oxygen containing
species, adsorbed at higher potentials and irreversibly desorbed, are
postulated for the (110) plane. The activity of the surface in the oxidation of
methanol is determined by its coverage with OHad species.
The other kind of species, found on the (110) surface, are inactive in this
reaction. The OHad species are the reactive intermediates in the proposed reaction.
Key
words: methanol oxidation; low-index planes of platinum; sodium hydroxide
solution; OH ion electrosorption; influence of OHad species;
reaction mechanism.
J.
Serb. Chem. Soc. 63(12) 1049-1052 (1998)
UDC 546.48:543.062
JSCS-2615
Original scientific paper
Kinetic determination of nanogramme
amounts of Cd(II) in solution
TODOR G. PECEV, RANGEL P. IGOV, ALEKSANDAR R. IGOV and SOFIJA M.
RANCIC
Department of Chemistry, Faculy of
Philosophy, University of Nis, YU-18000 Nis, Yugoslavia
(Received 4 May, revised
2 September 1998)
A new kinetic method is described for Cd(II)
traces determination, based on its inhibiting effect on the oxidation of
alizarine by hydrogen peroxide and in the presence of the constant
concentration of Co(II), as a catalyst, in solution. The sensitivity of 2.5×10-8 g cm-3 Cd(II) was achieved. The relative error ranges
between 2.5 and 20% for the concentration interval of 5×10-7 to 1×10-7 g cm-3. Appropriate kinetic
equations were formulated, and the effect of different ions upon the reaciton
rate was tested.
Key
words: kinetic method, Cd(II) determination.
Subject index
1061
Author index
1065
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