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1.
The synthesis and characterization of Ru2Cl(μ‐O2CCH2CH2OMe)4 ( 1 ), [Ru2(μ‐O2CCH2CH2OMe)4(H2O)2]BF4 ( 2 ), PPh4[Ru2Cl2(μ‐O2CCH2CH2OMe)4] ( 3 ), (PPh4)2[Ru2Br2(μ‐O2CCH2CH2OMe)4]NO3 ( 4 ), and (PPh4)2[Ru2I2(μ‐O2CCH2CH2OMe)4]I0.5(NO3)0.5 ( 5 ), are described. The structure of complexes 2 – 5 was established by single crystal X‐ray diffraction. All complexes show a diruthenium(II, III) unit bridged by four 3‐methoxypropionate ligands. The cationic complex 2 have two axially coordinated water molecules, with a Ru–Ru bond distance of 2.2681(12) Å. This complex shows a supramolecular two‐dimensional organization across hydrogen bonded between the axial water molecules and two methoxy groups of adjacent diruthenium units. The metal‐metal bond lengths, in the anionic complexes 3 , 4 , and 5 , are 2.3039(5), 2.3077(6), and 2.3115(8) Å, respectively. These distances are longer than the observed in compound 2 . In the anionic complexes, the axial positions of the diruthenium units are occupied by two halide ligands. Complexes 3 – 5 have PPh4+ cations as counterion, although 4 and 5 are double salts with PPh4NO3 and PPh4I0.5(NO3)0.5, respectively. All compounds have been also characterized by elemental analysis, magnetic measurements, and spectroscopic techniques.  相似文献   

2.
Phosphoraneiminato Acetate Cluster of Copper and Zinc. Crystal Structures of [Cu4(NPEt3)2(O2CCH3)6] and [Zn4(NPEt3)2(O2CCH3)6] The anhydrous acetates of copper(II) and zinc react with the silylated phosphaneimine Me3SiNPEt3 in dichloromethane at 20 °C forming the mixed phosphoraneiminato acetate clusters [Cu4(NPEt3)2(O2CCH3)6] ( 1 ), which forms emerald crystals, and colourless [Zn4(NPEt3)2 · (O2CCH3)6] ( 2 ). In spite of analogous composition the structures of 1 and 2 are completely different. In the asymmetric unit of 1 three copper atoms of an almost isosceles triangle are linked via two nitrogen atoms of the NPEt3– groups to form a trigonal bipyramidal aggregate. One of these three copper atoms is chelated by an acetate group, another one is connected with the fourth copper atom via three μ2‐O2C–CH3 groups. The asymmetric units are associated via a μ2‐O2C–CH3 group and a μ3‐OC(O)CH3 group at a time so that infinite chains result. In 2 two zinc atoms are linked via the nitrogen atoms of the two NPEt3– groups to form an almost centrosymmetric four‐membered ring. Both nitrogen atoms of the four‐membered ring are connected with another zinc atom each. These zinc atoms again are linked with the zinc atoms of the Zn2N2 four‐membered ring via two μ2‐O2C–CH3 groups each and additionally coordinated with a terminal acetate ligand each.  相似文献   

3.
Binuclear hexafluoroacetylacetonate complexes of Rh(II) with axial ligands (Py, H2O) exhibit activity in hydrogenation and isomerization of allylbenzene, and the isomerization reaction also takes place in an atmosphere of Ar. The catalytic system [Rh2(hfacac)4(H2O)2]-Ph3P is much more active than Rh(II) hexafluoroacetylacetonate complexes in transformation of allylbenzene. Treatment of the acetate complex [Rh2(O2CCH2)4] with sodium borohydride significantly increases its activity, probably due to the formation of [Rh2(O2CCH3)3]+ and [Rh2(O2CCH2)2]2+ complexes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 1957–1961, September, 1989.  相似文献   

4.
The cations Cobipy 2(CH2NH2)2+ formed through the photodecarboxylation of Cobipy 2(O2CCH2NH2)2+ have been shown by single-crystal X-ray diffraction to contain the three-membered Co-C-N cycles, with Co-C, Co-N, and C-N distances being 195, 194, and 141 pm respectively.
Ein neuer Typ von Organo-Kobaltkomplexen. Struktur von 2-Aminomethylenbis(2,2-bipyridyl)-kobalt (III) (Kurze Mitteilung)
Zusammenfassung Die durch Photodecarboxylierung von Cobipy 2(O2CCH2NH2)2+ gewonnenen Kationen Cobipy 2(CH2NH2)2+ enthalten einen dreigliederigen Ring Co-C-N der durch Einkristall-Röntgenstrukturanalyse bestätigt wurde. Die gefundenen Co-C-, Co-N- und C-N-Abstände betragen 195, 194 und 141 pm.
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5.
The values of the kinetic parametersE andA were determined by Kissinger's method on the basis of the DTA, DTG and DSC curves of particular stages of the thermal decomposition of [Co(NH3)6]2(C2O4)3· 4H2O in air and argon atmospheres. It is shown that the use of Kissinger's method for different kinds of experimental curves (DTA, DSC, DTG) leads to close results.
Zusammenfassung Für verschiedene Schritte der thermischen Zersetzung von [Co(NH3)6]2(C2O4)3· 4H2O in Luft bzw. Argon wurden nach dem Kissinger-Verfahren auf der Basis von DTA-, DTG- und DSC-Kurven Werte für die kinetischen ParameterE undA ermittelt. Es wurde gezeigt, daß das Kissinger-Verfahren für die verschiedenen Arten von experimentellen Kurven (DTA, DSC, DTG) genaue Ergebnisse liefert.
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6.
Kinetic parameters (apparent activation energy, reaction order, pre-exponential factor (Z) in the Arrhenius equation) for thermal decomposition of the [Co(NH3)6]Cl3, Co[(NH3)4Cl2]Cl, K3[Fe(C2O4)3]3H2O and Fe(CH3COO)3 are reported. They have been calculated on the DTA and TG data according to Coats-Redfern's model. Both, decomposition data obtained in argon and in air atmosphere have been considered and the results are compared.
Zusammenfassung Es werden die kinetischen Parameter (scheinbare Aktivierungsenergie, Reaktionsordnung, prÄexponentieller Faktor (Z) der Arrhenius-Gleichung) der thermischen Zersetzung von [Co(NH3)6]Cl3, [Co(NH3)4Cl2]Cl, K3[Fe(C2O4)3]3H2O und Fe(CH3COO)3 beschrieben, die entsprechend dem Coats-Redfern-Modell auf der Basis der DTA- und TG-Daten errechnet wurden. Die Zersetzung wurde sowohl in Argon als auch in Luft durchgeführt und die erhaltenen Daten miteinander verglichen.

Helpful comments from Professor W. Wojciechowski and financial support from Institute for Low Temperatures and Structure Research Polish Academy of Sciences (CPBP 01.12) are greatefully acknowledged.  相似文献   

7.
The mixed carboxylate diruthenium complexes trans-[Ru 2 II,III (O2CCH3)2(O2CAr)2Cl] (I) and trans-[Ru 2 II,II (O2CCH3)2(O2CAr)2] (II) (O2CAr = 2,6-di(p-tolyl)benzoate) have been synthesised along with [Ru 2 II,III (O2CAr)4Cl] (III) and the homoleptic complex [Ru 2 II,II (O2CAr)4] (IV). The structures trans-[Ru2(O2CCH3)2(O2CAr)2Cl(thf)]·(thf) and [Ru2(O2CAr)4Cl(η 1-CH2Cl2)] were determined by X-ray crystallography, and display the expected paddlewheel arrangement of the carboxylate ligands around the diruthenium core. The structure of III is a rare example of a structurally characterised dichloromethane complex, highlighting the Lewis acidic nature of the diruthenium axial position. The bulky ?O2CAr ligand protects the axial positions from intermolecular interactions in the absence of strong nucleophiles for III and IV, and the effect this has on the electronic structure of the diruthenium core in these complexes was investigated by cyclic voltammetry, electronic absorption spectroscopy and magnetic susceptibility studies.  相似文献   

8.
The compounds TlLn(SO4)2·2H2OLn=La, Ce, Pr, Nd and Tl[Ln(SO4)2(H2O)3]·H2OLn=Nd, Sm, Eu, Gd, Tb have been isolated from aqueous solutions of the corresponding sulfates. The dihydrates are all isomorphous and crystallize monoclinic, space groupP21/n,Z=4. The compounds which belong to the second type are also isomorphous and crystallize in monoclinic space groupP 21/c withZ=4.The dehydration has been studied by thermogravimetry, differential scanning calorimetry and isothermal weight change determination. The dihydrates dehydrate in a single step. For the tetrahydrates the reaction is more complex, however no intermediate phases could be isolated.The unit cell parameters, the dehydration temperatures and the dehydration enthalpies are correlated to the ionic radii ofLn 3+.
Synthese und Charakterisierung von TlLn(SO4)2·xH2O (Ln=La-Tb)
Zusammenfassung Die Verbindungen TlLn(SO4)2·2H2OLn=La, Ce, Pr, Nd und Tl[Ln(SO4)2(H2O)3]·H2OLn=Nd, Sm, Eu, Gd, Tb wurden aus wäßrigen Lösungen der entsprechenden Sulfate isoliert. Die Dihydrate sind alle isomorph und kristallisieren monoklin, RaumgruppeP 21/n,Z=4. Die Verbindungen des zweiten Typs sind auch isomorph und kristallisieren in der monoklinen RaumgruppeP 21/c mitZ=4.Die Dehydration wurde mit TG, DSC und dem isothermalen Gewichtsverlust untersucht. Die Entwässerung der Dihydrate verläuft in einer Stufe, die von Tetrahydraten aber in mehreren Stufen mit keiner isolierbaren Zwischenphase.Die Gitterkonstanten, die Dehydratations-Temperaturen und -Enthalpien wurden mit den Ionenradien vonLn 3+ korreliert.
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9.
Inhaltsübersicht. Die erstmals dargestellte Verbindung HgPb2O(OH)Br3 kristallisiert orthorhombisch in der Raumgruppe Aba2 (Nr. 41) mit den Gitterkonstanten a = 14,652(3) Å, b = 14,6491(8) Å, c = 7,782(2) Å und Z = 8. Die Bestimmung der Kristallstruktur mit Einkristallmethoden zeigte “isolierte”, verzerrt würfelförmige Baugruppen der Zusammensetzung [Hg2Pb4O2(OH)2]. Diese Einheiten werden von Bromidionen umhüllt. HgPb2O(OH)Br3 stellt damit hinsichtlich des strukturellen Aufbaus ein Bindeglied zwischen den Verbindungen [Pb4(OH)4](ClO4)4 · 2H2O [1] und Pb9O4Br10 [2] dar. Preparation and Crystal Structure of HgPb2O(OH)Br3 The new compound, HgPb2O(OH)Br3 was prepared and investigated by X-ray crystal structure analysis. Crystals of orthorhombic symmetry show space group Aba2 (No. 41) with lattice parameters a = 14.652(3) Å, b = 14.6491(8) Å, c = 7.782(2) Å, and Z = 8. Remarcable structural units with heterocubane skeleton were found. The [Hg2Pb4O2(OH)2] group forms a new member of the structural class between [Pb4(OH)4] and [Pb8O4] units with the relating compounds [Pb4(OH)4)](ClO4)4 · 2 H2O [1] und Pb9O4Br10 [2].  相似文献   

10.
Syntheses and Crystal Structures of New Selenido-bridged Ruthenium Clusters The reaction of Se(SiMe3)2 with [RuCl2(PPh3)3], or a mixture of [RuCl2(PPh3)3] and alkylphosphines leads to the formation of selenido-bridged ruthenium clusters. In this publication the compounds [Ru6Se8(PPh3)6] ( 1 ), [Ru6Se8(PEt3)6] ( 2 ) und[Ru6Se8(PnPr3)6] ( 3 ) are described.The compounds 1-3 contain Ru616+ cluster cores with Ru2+ and Ru3+ centers. The structures of these compounds were elucidated by single crystal X-ray structural analyses.  相似文献   

11.
The complete sequence of reactions in the base‐promoted reduction of [{RuII(CO)3Cl2}2] to [RuI2(CO)4]2+ has been unraveled. Several μ‐OH, μ:κ2‐CO2H‐bridged diruthenium(II) complexes have been synthesized; they are the direct results of the nucleophilic activation of metal‐coordinated carbonyls by hydroxides. The isolated compounds are [Ru2(CO)4(μ:κ2‐C,O‐CO2H)2(μ‐OH)(NPF‐Am)2][PF6] ( 1 ; NPF‐Am=2‐amino‐5,7‐trifluoromethyl‐1,8‐naphthyridine) and [Ru2(CO)4(μ:κ2‐C,O‐CO2H)(μ‐OH)(NP‐Me2)2][BF4]2 ( 2 ), secured by the applications of naphthyridine derivatives. In the absence of any capping ligand, a tetranuclear complex [Ru4(CO)8(H2O)2(μ3‐OH)2(μ:κ2‐C,O‐CO2H)4][CF3SO3]2 ( 3 ) is isolated. The bridging hydroxido ligand in 1 is readily replaced by a π‐donor chlorido ligand, which results in [Ru2(CO)4(μ:κ2‐C,O‐CO2H)2(μ‐Cl)(NP‐PhOMe)2][BF4] ( 4 ). The production of [Ru2(CO)4]2+ has been attributed to the thermally induced decarboxylation of a bis(hydroxycarbonyl)–diruthenium(II) complex to a dihydrido–diruthenium(II) species, followed by dinuclear reductive elimination of molecular hydrogen with the concomitant formation of the RuI? RuI single bond. This work was originally instituted to find a reliable synthetic protocol for the [Ru2(CO)4(CH3CN)6]2+ precursor. It is herein prescribed that at least four equivalents of base, complete removal of chlorido ligands by TlI salts, and heating at reflux in acetonitrile for a period of four hours are the conditions for the optimal conversion. Premature quenching of the reaction resulted in the isolation of a trinuclear RuI2RuII complex [{Ru(NP‐Am)2(CO)}{Ru2(NP‐Am)2(CO)2(μ‐CO)2}(μ3:κ3‐C,O,O′‐CO2)][BF4]2 ( 6 ). These unprecedented diruthenium compounds are the dinuclear congeners of the water–gas shift (WGS) intermediates. The possibility of a dinuclear pathway eliminates the inherent contradiction of pH demands in the WGS catalytic cycle in an alkaline medium. A cooperative binuclear elimination could be a viable route for hydrogen production in WGS chemistry.  相似文献   

12.
《Polyhedron》2002,21(12-13):1299-1304
The crystal structure of a trinuclear iron monoiodoacetate complex was determined. Although it has been incorrectly characterized as [Fe3O(O2CCH2I)6(H2O)3], the correct chemical formula turned out to be [Fe(III)2Fe(II)O(O2CCH2I)6(H2O)3]-[Fe(III)3O(O2CCH2I)6(H2O)3]I (1). The two kinds of Fe3O molecules (Fe(III)2Fe(II)O and Fe(III)3O) are crystallographically indistinguishable. All the Fe atoms are crystallographically equivalent because of a crystallographic threefold symmetry. Heat capacities of 1 seem to exhibit no thermal anomaly in the temperature range 5.5–309 K, although the valence detrapping phenomenon has been observed in this temperature range. This fact indicates that the valence-detrapping phenomenon in 1 occurs without any phase transition, leading 1 to a glassy state, probably because the crystal of 1 is just like a solid solution of distorted mixed-valence Fe(III)2Fe(II)O molecules and permanently undistorted Fe(III)3O molecules which may act as an inhibitor for a cooperative valence-trapping.  相似文献   

13.
From cyclic linear sweep voltammograms of some Cr(III) complexes it is evident that after electron transfer ligand groups are expelled relatively slowly inDMSO and the tetra coordinated complex is formed. The rate constants could be determined in some cases by the methods of cyclic voltammetry. The following compounds were examined: [Cr(en)3]3+, [Cr(acac)(en)2]2+, [Cr(acac)3]. [Cr(dien)2]3+, [Cr(DMSO)6]3+, [Cr(ur)6]3+. For [Cr(en)3]3+ the energy of activation could be determined as well.The dependence of the velocity of ligand elimination on complex structure is discussed.
Untersuchung von Ligandenaustauschreaktionen einiger Cr(III)-Komplexe mittels cyclischer Voltammetrie
Zusammenfassung Bei der Reduktion einiger der folgenden Cr(III)-Komplexe inDMSO läßt sich auf Grund der Voltammogramme auf eine Ligandenabspaltung und Bildung der vierfach koordinierten Cr(II)-Komplexe schließen: [Cr(en)3]3+, [Cr(acac)(en)2]2+, [Cr(acac)3], [Cr(dien)2]3+, [Cr(DMSO)6]3+, [Cr(ur)6]3+. Für das [Cr(en)3]3+ konnten Geschwindigkeitskonstante und Aktivierungsenergie dieser nachgelagerten Reaktion bestimmt werden.Der Einfluß der Struktur des Komplexes auf die Zerfallsgeschwindigkeit wird diskutiert.
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14.
Chemical and electrochemical oxidation of rhodium (III) oxo-bridged carboxylate complexes was studied. The chemical [with O3 and Ce(IV) salts] or electrochemical (at potentials of 1.00-1.20 V) oxidations of the binuclear complexes [Rh2(-O)(-O2CCH3)2(H2O)6]2 + and [Rh2(-O)(-O2CCF3)2(H2O)6]2 + leads to the superoxo complexes [Rh2(-O)(O2-)(-O2CCH3)2(H2O)5]+ and [Rh2(-O)(O2 -)(-O2CCF3)2(H2O)5]+ with terminal coordination of O2-. The trinuclear acetate [Rh3(3-O)(-O2CCH3)6(H2O)3]+, unlike its trifluoroacetate analog [Rh3(3-O)(-O2CCF3)6(H2O)3]+, is oxidized only electrochemically at a potential of 1.38 V. The oxidation of [Rh3(3-O)(-O2CCH3)6(H2O)3]+ is reversible and involves formation of an unstable superoxo group O2 - between two Rh3III(3-O) cores.  相似文献   

15.
Oxo-phosphoraneiminato Complexes of Molybdenum and Tungsten. Crystal Structures of [Mo(O)2(NPPh3)2] and [WO(NPPh3)3]2[W6O19] The dioxo-phosphoraneiminato complexes [Mo(O)2(NPPh3)2] ( 1 ) and [W(O)2(NPPh3)2] ( 2 ) originate from hydrolysis of the nitrido complexes [MN(NPPh3)3] (M = Mo, W). They form colourless crystals, which are characterized by IR and NMR spectroscopy as well as by mass spectrometry. According to the crystal structure analysis of 1 (space group Fdd2, Z = 8; lattice dimensions at –83 °C: a = 1953.3(1), b = 3275.8(3), c = 953.4(1) pm) there are monomeric molecules with tetrahedrally coordinated molybdenum atoms. The distances MoO of 171.2 pm and MoN of 185.9 pm correspond to double bonds. In dichloromethane solution 2 undergoes further hydrolysis with colourless crystals of [WO(NPPh3)3]2[W6O19] ( 3 ) originating, which are characterized crystallographically (space group Pbcn, Z = 4; lattice dimensions at –50 °C: a = 3225.1(6), b = 1803.6(3), c = 1811.9(3) pm). 3 consists of cations [WO(NPPh3)3]+ with tetrahedrally coordinated tungsten atoms and of the known [W6O19]2– anions. The tungsten atoms of the cations show distances WO of 171.8 pm and WN of 182 pm which correspond to double bonds as in 1 .  相似文献   

16.
Pb2(Hg3O4)(CrO4) consists of [CrO4]2− tetra­hedra, linear O—Hg—O dumbbells and divalent Pb atoms in [3+5]‐coordination. The HgO2 dumbbells are condensed into [Hg3O4]2− units and can be regarded as a section of the HgO structure. The [Hg3O4]2− complex anions are connected by inter­stitial Pb2+ ions, while the [CrO4]2− tetra­hedra are isolated.  相似文献   

17.
Cis-/Trans-Isomerism of Bis-(trisalkoxy)-hexavanadates: cis-Na2[V O7(OH)6{(OCH2)3CCH2OH}2] · 8 H2O, cis-(CN3H6)3[VIVV O13{(OCH2)3CCH2OH}2] · 4.5 H2O and trans-(CN3H6)2[V O13{(OCH2)3CCH2OH}2] · H2O Polyoxovanadates with distorted Lindquist-structure, in which six of the twelve μ2-oxygen atoms are formally replaced by the oxygen atoms of two coordinated pentaerythritol ligands, can be prepared by a simple method in an aqueous medium. The “fully reduced”, six-fold protonated compound cis-Na2[VO7(OH)6{(OCH2)3CCH2OH}2] · 8 H2O ( 1 ), the mixed valence species cis-(CN3H6)3[VIVVO13{(OCH2)3CCH2OH}2] · 4.5 H2O ( 2 ) containing one localized VIV centre and the “fully oxidized” compound trans-(CN3H6)2[VO13{(OCH2)3CCH2 · OH}2] · H2O ( 3 ) have been synthesized and characterized by UV/VIS-, IR- and EPR-spectroscopy, by magnetic measurements, cyclic voltammetry and by a single-crystal X-ray structure analysis. The organic {(CH2)3CCH2OH}3+-groups tend to cap the triangular faces formed by μ2-oxygen atoms of the central approximately octahedral {V6O19}-unit. Therefore the anions of bis-(trisalkoxy)-hexavanadates can exist in a trans-form as well as in an isomeric cis-form referring to a “basic” plane of four vanadium atoms of the {V6}-octahedron. The different relative positions of the ligands have a significant influence on the redox potentials of the compounds. For structural details see “Inhaltsübersicht”.  相似文献   

18.
利用水热法合成了两种过渡金属配合物为模板剂的含水硼酸盐晶体Co(en)3[B4O5(OH)4]Cl·3H2O(1) 和 [Ni(en)3][B5O6(OH)4]2·2H2O (2),并通过元素分析、X射线单晶衍射、红外光谱及热重分析对其进行了表征。化合物1晶体结构的主要特点是在所有组成Co(en)33+, [B4O5(OH)4]2–, Cl– 和 H2O之间通过O–H…O、O–H…Cl、N–H…Cl和N–H…O四种氢键连接形成网状超分子结构。化合物2晶体结构的特点是[B5O6(OH)4]–阴离子通过O–H…O氢键连接形成沿a方向有较大通道的三维超分子骨架,模板剂[Ni(en)3]2+阳离子和结晶水分子填充在通道中。  相似文献   

19.
Summary Single crystal X-ray data of the hydrothermally grown new phase Li2Cu3(SeO3)2(SeO4)2 were measured with a four-circle diffractometer up to sin /=0.81 Å–1 [I2/a,Z=4,V=1175.5 Å3,a=16.293(6),b=5.007(2),c=14.448(6) Å, = 94.21(1)°]. The structure was determined by direct and Fourier methods and refined toR=0.034,R w =0.027 for 2 086 independent reflections.Cu(1)[4+1]O5 forms a tetragonal pyramid, Cu(2)[4 + 2]O6 is a strongly elongated octahedron. The Li atom is surrounded by four O atoms forming a distorted tetrahedron. Se(IV)O3 and Se(VI)O4 groups are in accordance to literature, mean Se-O bond lengths are 1.714 and 1.644 Å.
Die Kristallstruktur von Li2Cu3(SeO3)2(SeO4)2
Zusammenfassung Einkristall-Röntgendaten der hydrothermal gezüchteten neuen Phase Li2Cu3(SeO3)2(SeO4)2 wurden mit einem Vierkreisdiffraktometer im Bereich bis zu sin /=0.81 Å–1 gemessen [I2/a,Z=4,V=1175.5 Å3,a=16.293(6),b=5.007(2),c=14.448(6) Å, =94.21(1)°]. Die Kristallstruktur wurde mittels direkter und Fourier-Methoden bestimmt und für 2 086 unabhängige Reflexe zuR=0.034,R w =0.027 verfeinert.Cu(1)[4+1]O5 bildet eine tetragonale Pyramide, Cu(2)[4+2]O6 ist ein stark verlängertes Oktaeder. Das Li-Atom ist von vier O-Atomen in Gestalt eines verzerrten Tetraeders umgeben. Die Se(IV)O3-und Se(VI)O4-Gruppen entsprechen der Literatur, die mittleren Se-O-Abstände betragen 1.714 und 1.644 Å.
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20.
Summary Stability constants of complexes of aryl-bis-(5-hydroxy-3-methyl-1-phenyl-4-pyrazolyl) methane [ArBPyM] derivatives with thorium(IV) ions were determined by the potentiometric method at 30°C and an ionic strength of 0.1 mol·dm–3 (KNO3) in 75% (v/v) dioxane-water. The evaluation of the titration data indicated that four kinds of complexes ([ThL]2+, [ThLOH]+, [ThL 2], and [ThL(OH)2]2–) were formed. The formation constants for all [ThL]2+ and [ThL 2] complexes have been calculated to compare these values with those previously reported [1, 2] with Ln3+ and UO 2 2+ metal ions [2, 3]. The probable ligand-bonding sites of the complexes are proposed. In addition, the applicability of theHammett equation for the correlation of the stability constants of [Th(IV)-ArBPyM] complexes are discussed.
Stabilitätskonstanten von Thorium(IV)-Komplexen mit Aryl-bis-(5-hydroxy-3-methyl-1-phenyl-4-pyrazolyl)-methan-Liganden
Zusammenfassung Stabilitätskonstanten von Komplexen von Aryl-bis-(5-hydroxy-3-methyl-1-phenyl-4-pyrazolyl)-methan — Derivaten [ArBPyM] mit Thorium(IV) — Ionen wurden bei 30°C und einer Ionenstärke von 0.1 mol-dm–3 (KNO3) in 75% (v/v) Dioxan-Wasser potentiometrisch bestimmt. Die Auswertung der Titrationskurven zeigte, daß vier verschiedene Komplexe vorlagen ([ThL]2+, [ThLOH]+, [ThL 2] und [ThL(OH)2]2+). Die Bildungskonstanten aller [ThL]2+- und [ThL 2]-Komplexe wurden berechnet, um sie mit den früher für Ln3+- und UO 2 2+ -Ionen publizierten zu vergleichen. Potentielle Bindungsstellen der Komplexe für Liganden werden vorgeschlagen. Zusätzlich wird die Anwendbarkeit derHammet-Beziehung auf die Korrelation der Stabilitätskonstanten von [Th(IV)-ArBPyM] — Komplexen diskutiert.
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