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1.
Vukadin M. Leovac Goran A. Bogdanović Valerija I. Češljević Ljiljana S. Jovanović Sladjana B. Novaković Ljiljana S. Vojinović-Ješić 《Structural chemistry》2007,18(1):113-119
The ligand, salicylaldehyde Girard-T hydrazonium chloride, [H2SalGT]Cl (1), and two complexes [Cu(HSalGT)X2]·H2O (X = Br(2); Cl(3)) were synthesized and their crystal structures were determined by single-crystal X-ray analysis. In the two isostructural
complexes, the Cu(II) is located in a square-pyramidal environment, with the chelating ligand and one halogen atom in the
basal plane and the second halogen in the apical position. The most apparent structural difference between the 1 and its complexes 2 and 3 is the orientation of the N(CH3)3 group: in 1, it is practically coplanar to the rest of the molecule, while in 2 and 3 it is oriented to the side of the axially bonded halogen, which can be explained by the C–H…X intramolecular interactions.
The compounds were characterized by elemental analysis, molar conductivity, magnetic susceptibility and electronic absorption
spectra. 相似文献
2.
V. M. Leovac E. Z. Ivegeš K. Mészáros Szécsényi K. Tomor G. Pokol S. Gal 《Journal of Thermal Analysis and Calorimetry》1997,50(3):431-440
Solvate complexes of UO 2 2+ andN(1), N(4)-bis(salicylidene)-S-methylisothiosemicarbazone, (H2Me-L1), of general formula [UO2(Me-L1)S] (S= H2O, MeOH, EtOH, Py, DMF and DMSO) were synthesized. The methanolic UO 2 2+ ” adducts of N(1)-benzoylisopropylidene-N(4)-salicylidene-S-alkylisothiosemicarbazone, (H2R-L2,R=Me, Prn) of general formula [UO2(R-L2)· MeOH], were also prepared. Thermal decomposition of the complexes was investigated in air and argon. The complexes decompose to α-U3O8 in air, while in argon the decomposition is not completed up to 1000 K. The temperature and the mechanism of decomposition of the complexes are a function of the solvent belonging to the inner coordination sphere. 相似文献
3.
D. Z. Obadovic V. M. Leovac A. F. Petrovic S. Yu. Chundak 《Journal of Thermal Analysis and Calorimetry》1990,36(7-8):2483-2492
A study was made of the thermal decomposition of octahedral Co(II) complexes of the type CoLn
X
2·mH2O, wheren=2 and 3,m=1,2 and 5 andX=Cl, Br, I, NCS, OAc andv
2So4, in both air and nitrogen atmospheres. It was established that the complexes are completely decomposed below 800° and CoO is formed as final product. The most probable decomposition mechanism was proposed. The tris(ligand) complexes were characterized by elemental analysis, and spectral and magnetic measurements, and all the data suggested the presence of a point group symmetry of type Oh.
Zusammenfassung Sowohl in Luft als auch in Stickstoffatmosphäre wurde die thermische Zersetzung von oktaedrischen Co(II)-Komplexen der allgemeinen Formel CoLnX2· mH2O (n=2 und 3,m=1, 2 und 5,X=Cl, Br, I, NCS, OAc und SO4) untersucht. Es wurde festgestellt, daß sich die Komplexe unterhalb 800°C vollkommen zu CoO als Endprodukt zersetzen. Der wahrscheinlichste Zersetzungsmechanismus wurde unterbreitet. Die tris-Ligandenkomplexe wurden mittels Elementaranalyse sowie Spektral- und magnetischen Untersuchungen charakterisiert, alle Angaben deuten auf eine Punktsymmetriegruppe vom Typ Oh hin.相似文献
4.
Vukadin M. Leovac Vladimir Divjaković Ana F. Petrović Nikolai V. Gerbeleu 《Monatshefte für Chemie / Chemical Monthly》1989,120(3):181-186
Summary The reaction of warmDMF solutions of Cu(II) perchlorate, 5-nitrosalicylaldehyde S-methylisothiosemicarbazone (H2
L) and piperidine (Pip) yielded the paramagnetic (eff=2.19 B.M.) Cu(L)Pip complex, whereL is the dianionic form of H2
L, formed as a result of deprotonation of the phenolic hydroxyl and NH2 group. Crystal data of the complex are: monoclinic P21,a=11.902(4),b=6.765(3),c=11.343(4)Å; =112.92°,V=841.20(8)Å3,M=400.9,Z=2,d
0=1.60 gcm–3,d
c
=1.58 gcm–3,F(000)=424. The structure was refined to a residualR=0.047. The copper(II) ion is coordinated in a square-planar arrangement by the piperidine nitrogen and the NNO set of donor atoms ofL.
Komplexe der Übergangsmetalle mit Thiosemicarbazid-Liganden, IV. Synthese und molekulare Struktur von 5-Nitrosalicylaldehyd-S-methylisothiosemicarbazonato-piperidin-kupfer(II)
Zusammenfassung Durch die Reaktion in warmenDMF-Lösungen von Cu(II) Perchlorat, 5-Nitrosalicylaldehyd-S-methylisothiosemicarbazon (H2 L) und Piperidin (Pip) wurde ein paramagnetischer Komplex (eff=2.19 B.M.) Cu(L)Pip erhalten, wobeiL nach doppelter Deprotonierung (NH2- und Phenolhydroxyl-Gruppe) als dianionische Form von H2 L vorliegt. Die kristallographischen Daten des Komplexes sind: monokline Raumgruppe P21,a=11.902(4),b=6.765(3),c=11.343(4)Å, =112.92°;V=841.20Å3,M=400.9,Z=2,d 0=1.60 gcm–3,d c =1.58 gcm–3,F(000)=424. Die struktur wurde bis zu einemR-Wert von 0.047 verfeinert. Die Koordination des Kupfers wird quadratisch-planar über den Piperidin-Stickstoff und die NNO-Donorhülle der Chelatliganden gebildet.相似文献
5.
Ferenc F. Gaál Vukadin M. Leovac Branislava Dj. Avramovi 《Fresenius' Journal of Analytical Chemistry》1973,266(5):355-357
Summary Tertiary amines and salts of organic acids in acetic anhydride with 5% of acetic acid were titrated applying a biamperometric indicating system consisting of a polarised or unpolarised pair of tin electrodes by means of 0.1 N perchloric acid in glacial acetic acid. Amounts of 15.4–29.8 mg were analysed with average deviations of <0.6%, the results obtained being in a good agreement with those of potentiometry. The biamperometric end-point detection using an indicating system of polarised pair of tin electrodes can be applied for coulometric determinations of these bases with satisfying accuracy. By means of anodic generation of hydrogen ions in the presence of hydroquinone amounts of 0.5–1.0 mg were titrated with average deviations of < 1.3%. The results obtained were compared with those obtained of catalytic thermometric and photometric titrations.
Biamperometrische Neutralisationstitrationen in nichtwärigen Lösungsmitteln unter Anwendung eines Zinn-Elektrodenpaares als Indicatorsystem
Zusammenfassung Tertiäre Amine und Salze organischer Säuren werden in Acetanhydrid mit 5% Essigsäure durch Titration mit einer 0,1 N Lösung von Perchlorsäure in Essigsäure bestimmt. Das verwendete biamperometrische Indicatorsystem besteht aus einem Paar polarisierter oder nichtpolarisierter Zinnelektroden. Mengen von 15,4–29,8 mg wurden mit einer mittleren Abweichung von <0,6% analysiert. Die Ergebnisse stimmen gut mit denen von potentiometrischen Titrationen überein. Die biamperometrische Endpunkttechnik mit polarisierten Zinnelektroden kann für coulometrische Bestimmungen dieser Basen mit zufriedenstellender Genauigkeit benutzt werden. Durch anodische Erzeugung von Wasserstoffionen in Gegenwart von Hydrochinon wurden Mengen von 0,5–1,0 mg mit einer mittleren Abweichung von < 1,3% titriert. Die Ergebnisse wurden mit denen von katalytisch-thermometrischen und photometrischen Titrationen verglichen.相似文献
6.
D. Z. Obadovic D. M. Petrovic V. M. Leovac S. Caric 《Journal of Thermal Analysis and Calorimetry》1990,36(1):99-108
The thermal decompositions of acetone 1-naphthoylhydrazone (L) and its octahedral complexes with Ni(II), with the general formula NiL2X2 (X=Cl, Br, NO3 and NCS), were studied in air and nitrogen atmospheres. It was established that the organic ligand is decomposed in an exothermic processes, which is followed by oxidation of the decomposition fragments by atmospheric oxygen. At temperatures below 640°, all the complexes decompose completely, yielding NiO as the final product, which was confirmed by its X-ray analysis. From the difference between the enthalpy changes for the decompositions of the complexes and of the ligand itself, the nature of the final oxide, and the crystal field splitting parameters obtained from optical measurements, the corresponding stabilization energies were determined.
Zusammenfassung In Luft- und Stickstoffatmosphäre wurde die thermische Zersetzung von Azeton-1-naphthoylhydrazon (L) und seinen oktaedrischen Komplexen mit Ni(II) mit der allgemeinen Formel NiL2X2 (mit X=Cl, Br, NO3 und NCS) untersucht. Es wurde festgestellt, daß der organische Ligand in einem exothemen Prozeß einer Zersetzung und einer anschließenden Oxydation der Zersetzungsprodukte durch Luftsauerstoff unterliegt. Unterhalb 640° zerfällen alle Komplexe vollständig und liefern NiO als Endprodukt, welches mittels Röntgendiffraktionsanalyse identifiziert wurde. Aus dem Unterschied zwischen Enthalpieänderungen für die Zersetzung der Komplexe und des Liganden selbst, aus der Art der erhaltenen Oxide und aus den Parametern der durch optische Messungen bestimmten Kristallfeldaufspaltung wurden die entsprechenden Stabilisierungsenergien bestimmt.相似文献
7.
Petrović A. F. Petrović D. M. Leovac V. M. Budimir M. 《Journal of Thermal Analysis and Calorimetry》1999,58(3):589-596
The paper describes the results of differential thermal analysis of the octahedral Fe(III) complexes of the general formula [Fe(HLn)2]Cl and Fe(HL3)L3, as well as of the corresponding ligands H2Ln (H2Ln — tridentate salicylaldehyde semi thiosemi- and S-methylisothiosemi-carabazones with n=1, 2 and 3 respectively). The decomposition of the complexes involving sulphur-containing ligands (H2L2 and H2L3) starts with sulphur elimination. In case of the complexes [Fe(HL2)]Cl and [Fe(HL3)]Cl sulphur evolves independently, whereas with Fe(HL3)L3 it is eliminated within the SCH3 group. In the former case, sulphur elimination takes place at the same temperature for both complexes. The change in the coordination mode, being a consequence of the replacement of O by S, has no essential effect on thermal stability of the coordination polyhedron. The complexes involving ONN coordination, realized with the H2L3 ligand, exhibit a comparatively highest thermal stability of the coordination polyhedron.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
8.
Mészáros Szécsényi K. Leovac V. M. Jaćimović Ž. K. Češljević V. I. Kovács A. Pokol G. 《Journal of Thermal Analysis and Calorimetry》2001,66(2):573-581
The synthesis of copper(II) chloride complexes with 3,5-dimethylpyrazole, 1-carboxamidine-3,5-dimethylpyrazole, 5-amino-4-carboxamide-1-phenylpyrazole
and 4-acetyl-3-amino-5-methylpyrazole is described. The compounds are characterized by elemental analysis, FT-IR spectroscopy,
thermal methods, magnetic moment and molar conductivity measurements. Thermal decomposition of the dichloro-(3,5-dimethylpyrazole)-copper(II)
complex results in an unstable intermediate with a stochiometric composition. The decomposition of the other compounds is
continuous.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
9.
Summary The reaction of warm alcoholic solutions of acetates of CoII, MnII, ZnII and NiII with 2, 6-diacetylpyridine andS-methylisothiosemicarbazide hydrogen iodide yielded the complexes: [Co(H2L)I2]·H2O, [Mn(H2L)(MeOH)2]I2, [Zn(H2L)(MeOH)I]I and [Ni(HL)]I, (H2L=the pentadentate pentaaza-ligand 2, 6-diacetylpyridine bis(S-methylisothiosemicarbazone)). The reaction of methanolic solutions of [Ni(HL)]I and NH4NCS or LiOAc.2H2O, give [Ni(HL)]NCS and NiL, respectively. For the complexes of CoII, MnII and ZnII, a pentagonal bipyramidal configuration is proposed, with H2L in the equatorial plane and two unidentate ligands (I and/or MeOH) in the axial positions. The complexes [Ni(HL)]X (X=I or NCS) and NiL probably have monomeric five- and dimeric six-coordinate structures, respectively, in which only the chelate ligand is involved in coordination. 相似文献
10.
A template synthesis procedure yielded [Ni(HL1)NH3]I, where HL1 is the monoanion of the terdentate ONN benzoylacetone S-methylisothiosemicarbazone ligand. The reaction of this complex with an excess of NH4NCS, pyridine, or hydrazine resulted in the complexes [Ni(HL1)(NH3)NCS] and [Ni(L1)A] (A = Py, N2H4). The monoanionic form of the ligand is obtained by deprotonation of the enolic form of the benzoylacetone moiety, whereas the dianion is formed by additional deprotonation of the terminal NH2 group. Finally, the reaction of [Ni(HL1)NH3]I with salicyladehyde produced the NiL2 complex in which L2 stands for the dianion of the ONNO ligand N(1)-2-butylidene-4-oxo-4-phenyl-N(4)-salicylidene-S-methylisothiosemicarbazide. All complexes are diamagnetic and have a square-planar configuration, except for [Ni(HL1)(NH3)NCS], for which te data of i.r. spectra suggest a square-pyramidal structure. The electronic absorption spectra of the ethanolic solutions of all complexes are characteristic of typical square-planar coordination of nickel(II). 相似文献