VII Zwei Oxidationsstufen und vier verschiedene Koordinationen von Eisen in einer Verbindung. Synthese,Kristallstruktur und spektroskopische Charakterisierung von 1,4‐Dimethylpiperazinium‐Chloroferrat(II,III), (dmpipzH2)6[FeIICl4]2[FeIIICl4]2[FeIICl5] [FeIIICl6]

Halogeno Metallates of Transition Elements with Cations of Nitrogen‐containing Heterocyclic Bases. VII Two Oxidation States and Four Different Iron Coordinations in one Compound. Synthesis, Crystal Structure, and Spectroscopic Characterization of 1,4‐Dimethylpiperazinium Chloroferrate(II, III), (dmpipzH₂)₆[Fe^IICl₄]₂[Fe^IIICl₄]₂[Fe^IICl₅] [Fe^IIICl₆] The title compound being stable on air crystallizes from aqueous hydrochloric acid solutions in the trigonal space group R3 with a = 13,197(1), c = 38,405(6) Å. Besides the cations in chair form, the structure contains six discrete, mononuclear chloroferrate anions arranged on a threefold axis. Tetrahedral, octahedral, and, for the first time with iron(II), trigonal bipyramidal metal coordinations occur. Four sub‐spectra contributing to the ⁵⁷Fe Mössbauer spectrum can be distinguished and have been attributed to all four types of chloroferrate anions in the structure. The Raman spectroscopic investigation of orientated single crystals allows to recognize polarized and non‐polarized vibrations as well as to attribute all observed frequencies.     

Halogenometallate von Übergangselementen mit Kationen stickstoffhaltiger heterocyclischer Basen. I. Die Kristallstrukturen von 1,4-Dimethylpiperazinium-tetrachlorocobaltat(II) und -zinkat(II), (dmpipzH2)[MIICl4] (M = Co,Zn)

Halogenometalates of Transition Elements with N-heterocyclic Base Cations. I. The Crystal Structures of 1,4-Dimethylpiperazinium Tetrachlorocobaltate(II) and -zincate(II), (dmpipzH₂)[M^IICl₄] (M = Co, Zn) The compounds (dmpipzH₂)[M^IICl₄] crystallize in the monoclinic space group P2₁/m with a = 6.133(1), b = 14.306(1), c = 6.902(1) Å, β = 90.54(2)°, Z = 2 for M = Co and with a = 6.141(1), b = 14.282(1), c = 6.907(1) Å, β = 90.60(2)°, Z = 2 for M = Zn. The structures consist of tetrahedra [MCl₄]^2? and centrosymmetric cations (dmpipzH₂)²⁺ in the chair form. Bifurcated hydrogen bridging bonds of the N? H …? Cl type connect the nitrogen atom to two chloride ions. Two short distances C …? Cl are interpreted in terms of C? H …?Cl hydrogen bridges.     

Monomere und polymere Dimethylaminothioquadratato‐Komplexe: Die Kristallstrukturen von Nickel(II)‐, Cobalt(II)‐, Silber(I)‐, Platin(II)‐, Gold(I)‐, Quecksilber(II)‐ und Blei(II)‐Dimethylaminothioquadrataten

Monomeric and Polymeric Dimethylaminothiosquarato Complexes: The Crystal Structures of Nickel(II), Cobalt(II), Silver(I), Platinum(II), Gold(I), Mercury(II) and Lead(II) Dimethylaminothiosquarates The ligand 2‐dimethylamino‐3, 4‐dioxo‐cyclobut‐1‐en‐thiolate, Me₂N‐C₄O₂S⁻ (L) forms neutral and anionic complexes with nickel(II), cobalt(II)‐, silver(I)‐, platinum(II)‐, gold(I)‐, mercury(II)‐ and lead(II). According to the crystal structures of seven complexes the ligand is O, S‐chelating in [Ni(L)₂(H₂O)₂]·2 H₂O, [Co(L)₂(CH₃OH)₂] and (with limitations) in [Pb(L)₂·DMF]. In the remaining compounds the ligand behaves essentially as a thiolate ligand. The platinum, gold and mercury complexes [TMA]₂[Pt(L)₄], [TMA] [Au(L)₂] and [Hg(L)₂] are monomeric. In [TMA][Ag₂(L)₃]·5.5 H₂O a chain‐like structure was found. In the asymmetric unit of this structure eight silver ions, with mutual distances in the range 2.8949(4) to 3.1660(3)Å, are coordinated by twelve thiosquarato ligands. [Pb(L)₂·DMF] has also a polymeric structure. It contains a core of edge‐bridged, irregular PbS₄ polyhedra. TMA[Au(H₂NC₄O₂S)₂] has also been prepared and its structure elucidated.     

The excited states of bipyridyl and phenanthroline complexes of Fe(III), Ru(II) and Ru(III): A molecular orbital study

The semiempirical zero-differential-overlap molecular orbital model which was shown in earlier papers in this series to give a good account of the charge transfer and -* spectra of Fe(II) complexes with conjugated ligands such as 2,2-bipyridyl and 1,10-phenanthroline is extended to complexes having openshell ground states, such as those of Fe(III), and to complexes of Ru(II) and Ru(III). The results are used to assign the observed charge transfer and intra-ligand absorption bands to specific orbital transitions. Observed and calculated intensities are in good agreement: reasons are advanced for the much lower intensity of the charge transfer bands in Ru(III) compared to Ru(II) complexes.     

Synthesis,characterization and magnetism of copper(II)‐lanthanide(III) heterobimetalic complexes with N,N'‐oxamidobis‐(benzoato)cuprate (II)

Seven new μ‐oxamido copper(II)‐lanthanide(III) heterobimetalic complexes described by the formula Cu(obbz) Ln‐(Ph‐phen)₂NO₃(Ln = La, Nd, Eu, Gd, Tb, Ho, Er), where obbz denotes the oxamidobis(benzoato) and Ph‐phen represents 5‐phenyl‐1, 10‐phenanthroline, have been synthesized and characterized by the elemental analyses, spectroscopic (IR, UV, ESR) studies, magnetic moments (at room temperature) and molar conductivity measurement. The temperature dependence of the magnetic susceptibility of Cu(obbz)Gd(Ph‐phen)₂NO₃ complex has been measured over the range 4.2–300 K. The least‐squares fit of the experimental susceptibilities based on the spin Hamiltonian operator, ? = ?2 J?₁·?₂, yielded J= +1.28 cm^?1, a weak ferromagnetic coupling, A plausible mechanism for a ferromagnetic coupling between Gd(III)‐Cu(II) is discussed in terms of spin‐polarization.     

Reaktionen von Lanthanoidhalogeniden mit Alkalibenzylverbindungen. Darstellung und Kristallstrukturen von [(tmeda)(C6H5CH2)2Y(μ-Br)2Li(tmeda)], [(tmeda)2SmBr(μ-Br)2Li(tmeda)] und [(dme)2SmBr(μ-Br)]2

Reactions of Lanthanide Halides with Alkalibenzyl Compounds. Synthesis and Crystal Structures of [(tmeda)(C₆H₅CH₂)₂Y(μ-Br)₂Li(tmeda)], [(tmeda)₂SmBr(μ-Br)₂Li(tmeda)] and [(dme)₂SmBr(μ-Br)]₂ Alkali-benzyl compounds react via a metathesis reaction with lanthanide halides to benzyl complexes of the rare earths. Reaction of [(C₆H₅CH₂)Li(tmeda)] with YBr₃ leads to the complex [(tmeda)Y(C₆H₅CH₂)₂ (μ-Br)₂Li(tmeda)] 1 , in which Yttrium and lithium are linked via two bromide bridges. However, the reaction of [(C₆H₅CH₂)Li(tmeda)] with SmBr₃ in toluene/tmeda leads under reduction of the Sm ion to the compound [(tmeda)₂SmBr(μ-Br)₂Li(tmeda)] 2 . 2 reacts with DME to yield the dimeric compound [(dme)₂SmBr(μ-Br)]₂ 3 . The structures of 1 – 3 were determined by X-ray single crystal structure analysis:

• 1: Space group P2₁/c, Z = 4, a = 829.5(6) pm, b = 1477.9(11) pm, c = 2575.0(10) pm, β = 92.03(6)°,
• 2: Space group P2₁, Z = 2, a = 954,7(3) pm, b = 1338.5(6) pm, c = 1244.9(5) pm, β = 107.51(3)°,
• 3: Space group P1 , Z = 1, a = 797.2(7) pm, b = 818.3(7) pm, c = 1169.7(8) pm, α = 100.96(6)°, β = 92.03(6)°, γ = 91.75(7)°.

     

Darstellung und Strukturanalyse neuer Komplexe von Eisen(II), Cobalt(II) und Nickel(II) nach synergistischer Extraktion

Zusammenfassung Die synergistische Extraktion von Eisen(II)-, Cobalt(II)- und Nickel(II)-Komplexen wird untersucht. Verwendet werden fluorierte Diketone (A) (Derivate des Thenoyltrifluoracetons) und eine neue Gruppe Schiff' scher Basen. Aus den Extraktionskurven nach der Job- und Molar-Ratio-Methode, der Elementaranalyse und aus Molmassenbestimmungen werden Komplexverbindungen der Zusammensetzung [M₄A₈B⁴] nachgewiesen. Aus den Elektronen- und IR-Spektren und aus magnetischen Messungen wird für die Ni(II)-Komplexe eine octaedrische Struktur vorgeschlagen.

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Preparation and structure analysis of new iron(II), cobalt(II) and nickel(II) complexes by synergistic extraction

Summary The synergistic extraction of iron(II), cobalt(II) and nickel(II) complexes was investigated. Fluorinated diketones (A) (derivates of thenoyltrifluoracetones) and a new group of Schiff bases were used. By Job and molar-ratio method investigation on the extraction curves, by elementary analysis and molar mass detection, complex compounds of the composition [M₄A₈B⁴] could be proved. Electron and infrared spectra and magnetical measurements led to an octahedral structure proposal for the Ni(II)-complexes.

Mein Dank gilt besonders Herrn Professor Dr. H. Specker, Direktor des Instituts für Anorganische Chemie I der RUB, für die Zurverfügungstellung der Geräte und Chemikalien, Herrn Professor Dr. Metfessel und Frau Dr. Magdela Gronau für die magnetischen Messungen in der Abteilung Physik der RUB.     

A novel crystal structure of {tris[4‐(1H‐pyrazol‐3‐yl‐κN2)‐3‐azabut‐3‐enyl]amine‐κN}iron(II) bis(tetrafluoridoborate) methanol monosolvate featuring a low‐spin configuration

Mononuclear complexes are good model systems for evaluating the effects of different ligand systems on the magnetic properties of iron(II) centres. A novel crystal structure of the title compound, [Fe(C₁₈H₂₄N₁₀)](BF₄)₂·CH₃OH, with one molecule of methanol per formula unit exhibits a strictly sixfold coordination sphere associated with a low‐spin configuration at the metal centre. The incorporated methanol solvent molecule promotes extended hydrogen‐bonding networks between the tetrafluoridoborate anions and the cationic units. A less constrained crystal structure regarding close contacts between the tetrafluoridoborate anions and the cationic units allows a spin transition which is inhibited in the previously published hydrate of the title compound.     

Synthese,Kristallstrukturen und Eigenschaften von Lanthanoid(III)-Komplexen mit 7-Oxa-bicyclo[2.2.1]heptan-2,3-dicarbonsäure

Synthesis, Crystal Structures, and Properties of Lanthanoid(III) Complexes with 7-Oxa-bicyclo[2.2.1]heptane-2,3-dicarboxylic Acid The synthesis of coordination compounds [ML(HL)(H₂O)] with M = La³⁺, Ce³⁺, Pr³⁺, Nd³⁺ and H₂L = 7-oxa-bicyclo[2.2.1]heptane-2-exo,3-cis-dicarboxylic acid ( 1 ) has been described. Results of IR spectroscopy and thermal decomposition are given. As a result of X-ray analyses, the four investigated lanthanoid(III) complexes are isotypic. Their stereochemistry approximates to the tri-capped trigonal prism with nine O atoms coordinating the metal atom. The bicyclic ligand acts as a tridentate chelating monoanion HL^? as well as a pentadentate dianion L^2? with both chelating and bridging function. One coordination place at the metal atom is occupied by a water molecule.     

Synthesis,Characterization and Magnetic Studies of μ‐Oxamido Copper (II) ‐ Chromium (III) Heterodinuclear Complexes

Three new μ‐oxamido‐bridged heterodinuclear copper (II)‐chromium (III) complexes formulated [Cu(Me₂oxpn)Cr‐(L)₂](NO₃)₃, where Me₂oxpn denotes N,N'‐bis(3‐amino‐2, 2‐dimethylpropyl)oxamido dianion and L represents 5‐methyl‐1,10‐phenanthroline (Mephen), 4,7‐diphenyl‐1,10‐phenanthroline (Ph₂phen) or 2,2′‐bipyridine (bpy), have been synthesized and characterized by elemental analyses, IR and electronic spectral studies, magnetic moments of room‐temperature and molar conductivity measurements. It is proposed that these complexes have oxamido‐bridged structures consisting of planar copper (II) and octahedral chromium (III) ions. The variable temperature magnetic susceptibilities (4.2–300 K) of complexes [Cu(Me₂oxpn)Cr(Ph₂phen)₂](NO₃)₃ (1) and [Cu(Me₂oxpn)Cr(Mephen)₂] (NO₃)₃ (2) were further measured and studied, demonstrating the ferromagnetic interaction between the adjacent chromium (III) and copper (II) ions through the oxamido‐bridge in both complexes 1 and 2. Based on the spin Hamiltonian, ? = ‐ 2J?₁ · ?₂, the exchange integrals J were evaluated as + 21.5 an^?1 for 1 and + 22.8 cm^?1 for 2.     

Molekülstrukturen von Kupfer(II)- und Eisen(III)-Chlorokomplexen mit di- und monoprotoniertem N-(Pyrid-2-ylmethyl)ethylendiamin-N,N′,N′-triacetat (H2pedta−; Hpedta2−)

Molecular Structures of Copper(II) and Iron(III) Chloro Complexes with di- and monoprotonated N-(pyrid-2-ylmethyl)ethylenediamine-N,N′,N′-triacetate (H₂pedta^?; Hpedta^2?) The molecular structures of two complexes of di- and monoprotonated N-(pyrid-2-ylmethyl)ethylenediamine-N,N′,N′ -triacetate (pedta^3?) with Cu^II and Fe^III as central atoms have been determined by single crystal X-ray diffraction methods. Both complexes have a distorted octahedral coordination with H₂pedta^? and Hpedta^2? as pentadentate ligands and a chloride ion occupying the sixth coordination site. The different oxidation states of the central atoms result in a completely different coordination behaviour of the carboxyl groups. In both complexes one of the ? CH₂? COOH groups is uncoordinated. In the Fe^III complex, the central atom is coordinated by the hydroxylic O atoms of the deprotonated carboxyl groups. Contrary to this in the Cu^II complex, the central atom is coordinated by the carbonylic O atoms. One of the coordinated carboxyl groups is protonated and the other is deprotonated. All protonated carboxyl groups in both complexes form intermolecular hydrogen bonds.     

Ligandenaustauschreaktionen von Bis(acetylacetonato)dioxo-molybdän(VI). Kristallstrukturen von [Salicylaldehyd-benzoylhydrazonato(2–)]dioxo-methanol-molybdän(VI) und [Benzoylaceton-benzoylhydrazonato(2–)] dioxo-triphenylphosphanoxid-molybdän(VI)

Ligand Exchange Reactions of Bis(acetylacetonato)dioxo-molybdenum(VI). Crystal Structures of [Salicylaldehyde-benzoylhydrazonato(2–)]dioxo-methanol-molybdenum(VI) and [Benzoylacetone-benzoylhydrazonato(2–)]dioxo-triphenylphosphaneoxide-molybdenum(VI) The products of ligand exchange reactions between bis(acetylacetonato)dioxo-molybdenum(VI) and tridentate diacidic ligands H₂L in the presence of triphenylphosphane were found by mass spectrometry to be complexes of the type MoO₂L. In the case of salicylaldehyde 2-hydroxyanil MoL₂ could also be identified. The compounds MoO₂L were crystallized as complexes with methanol or triphenylphosphane oxide. Crystallographic data see “Inhaltsübersicht”.     

The first three‐dimensional FeIII–SrII heterometallic coordination polymer: poly[[diaquatetrakis(μ3‐pyridine‐2,3‐dicarboxylato)diiron(III)strontium(II)] dihydrate]

The title compound, poly[[diaqua‐1κ²O‐tetrakis(μ₃‐pyridine‐2,3‐dicarboxylato)‐2:1:2′κ¹⁰N,O²:O^2′,O³:O^3′;2:1:2′κ⁸O³:O^3′:N,O²‐diiron(III)strontium(II)] dihydrate], {[Fe₂Sr(C₇H₃O₄)₄(H₂O)₂]·2H₂O}_n, which has triclinic (P) symmetry, was prepared by the reaction of pyridine‐2,3‐dicarboxylic acid, SrCl₂·6H₂O and Fe(OAc)₂(OH) (OAc is acetate) in the presence of imidazole in water at 363 K. In the crystal structure, the pyridine‐2,3‐dicarboxylate (pydc²⁻) ligand exhibits μ₃‐η¹,η¹:η¹:η¹ and μ₃‐η¹,η¹:η¹,η¹:η¹ coordination modes, bridging two Fe^III cations and one Sr^II cation. The Sr^II cation, which is located on an inversion centre, is eight‐coordinated by six O atoms of four pydc²⁻ ligands and two water molecules. The coordination geometry of the Sr^II cation can be best described as distorted dodecahedral. The Fe^III cation is six‐coordinated by O and N atoms of four pydc²⁻ ligands in a slightly distorted octahedral geometry. Each Fe^III cation bridges two neighbouring Fe^III cations to form a one‐dimensional [Fe₂(pydc)₄]_n chain. The chains are connected by Sr^II cations to form a three‐dimensional framework. The topology type of this framework is tfj . The structure displays O—H...O and C—H...O hydrogen bonding.     

Eisen(II)—Phosphin-Komplexe Synthese und Kristallstrukturen von [Fe2I4(dppe)2], [Fe2(SR)4(dppe)2], [Fe(SR′)2(dppp)] und [Fe(SR)2(PMePh2)2] (dppe = Ph2P(CH2)2PPh2; dppp = Ph2P(CH2)3PPh2; R = 2,4,6-Me3C6H2; R′ = 2,4-tBuC6H3)

Iron(II) Phosphane Complexes. Synthesis and Crystal Structures of [Fe₂I₄(dppe)₂], [Fe₂(SR)₄(dppe)₂], [Fe(SR′)₂(dppp)] and [Fe(SR)₂(PMePh₂)₂] (dppe = Ph₂P(CH₂)₂PPh₂; dppp = Ph₂P(CH₂)₃PPh₂; R = 2,4,6-Me₃C₆H₂; R′ = 2,4-tBuC₆H₃) The title compounds were isolated and their structures determined by crystallographic methods. [Fe₂I₄(dppe)₂] ( 1 ) and [Fe₂(SR)₄(dppe)₂] ( 2 ) form dimeric complexes with the bidentate phosphane binding to different iron atoms. The resulting ten-membered rings of both compounds exhibit a nearly identical conformation. The central FeS₂P₂ units of the mononuclear complexes [Fe(SR′)₂(dppp)] ( 3 ) and [Fe(SR)₂(PMePh₂)₂] ( 4 ) show like 2 large deviations from ideal C_2v symmetry with bonding angles around the central iron atom ranging from 97.2, 92.5, and 96.5° (angle P? Fe? P in 2, 3 , and 4 , respectively) to 129.0, 129.9, and 133.6° (angle S? Fe? S in 2, 3 , and 4 , respectively).     

Synthese und Kristallstrukturen der Thiochloroantimonate(III) PPh4[Sb2SCl5] und (PPh4)2[Sb2SCl6] · CH3CN

Syntheses and Crystal Structures of the Thiochloroantimonates(III) PPh₄[Sb₂SCl₅] and (PPh₄)₂[Sb₂SCl₆]. CH₃CN (PPh₄)₂Sb₃Cl₁₁, obtained from Sb₂S₃, PPh₄Cl and HCl, reacts with Na₂S₄ in acetonitrile forming PPh₄[Sb₂SCl₅]. From this and Na₂S₄ or from (PPh₄)₂[Sb₂Cl₈] and Na₂S₄ or K₂S₅ in acetonitrile (PPh₄)₂[Sb₂SCl₆] · CH₃CN is obtained. Data obtained from the X-ray crystal structure determinations are: PPh₄[Sb₂SCl₅], monoclinic, space group P2₁/c, a = 1002.9(3), b = 1705.6(5), c = 1653.7(5) pm, β = 99.12(2)°, Z = 4, R = 0.068 for 1283 reflextions; (PPh₄)₂[Sb₂SCl₆] · CH₃CN, triclinic, space group P1 , a = 1287.8(7), b = 1343.6(9), c = 1696.5(9) pm, α = 69.82(5), β = 85.08(4), γ = 71.54(6)°, Z = 2, R = 0.059 for 6409 reflexions. In every anion two Sb atoms are linked via one sulfur and one ore two chloro atoms, respectively. Paris of [SbSCl₅]^? ions are associated via Sb …? S and Sb …? Cl contacts forming dimer units. In both compounds every Sb atom has a distorted octahedral coordination when the lone electron pair is included in the counting.     

Reaktionen und thermisches Verhalten oxofreier Vanadium(IV)-Komplexe. Kristallstrukturen von Methoxo-oxo[thenoyltrifluoraceton-salicylhydrazonato(2−)]vanadium(V) und Methoxo-oxo[benzoylaceton-salicylhydrazonato(2−)]vanadium(V)

Reactions and Thermal Behaviour of Nonoxo Vanadium(IV) Complexes. Crystal Structures of Methoxo-oxo[thenoyltrifluoroacetone-salicylhydrazonato(2–)]vanadium(V) and Methoxo-oxo[benzoylacetone-salicylhydrazonato(2–)]vanadium(V) The persistence of non-oxo vanadium(IV) complexes in dichlormethane/methanol/water solutions was studied by UV/VIS spectroscopy. The reaction products methoxo-oxo-[thenoyltrifluoroacetone-salicylhydrazonato(2–)]vanadium(V) and methoxo-oxo[benzoylacetone-salicylhydrazonato(2–)]vanadium(V) were isolated and characterized by X-ray analysis. The thermal behaviour of non-oxo vanadium(IV) complexes was checked.     

Synthese,Charakterisierung und Kristallstrukturen von Tetraiodoferraten(III)

Preparation, Characterization, and Crystal Structures of Tetraiodoferrates(III) The extremely air and moisture sensitive tetraiodoferrates MFeI₄ with M = K, Rb and Cs have been synthesized by reaction of Fe, MI and I₂ at 300°C in closed quartz ampoules. The essentially more stable alkylammonium tetraiodoferrates NR₄FeI₄ with R = H, C₂H₅, n-C₃H₇, n-C₄H₉ and n-C₅H₁₁ can be obtained by reaction of Fe, NR₄I and I₂ in nitromethane. The Raman and UV/Vis-spectra of the black compounds show the existence of tetrahedral [FeI₄]^? ions in the structures. The crystal structure of the monoclinic CsFeI₄ (CsTlI₄ type, spgr P2₁/c; a = 7.281(1) Å; b = 17.960(3) Å; c = 8.248(2) Å; β = 107.35(15)°) is built up by tetrahedral [FeI₄]^? ions and CsI₁₁ polyhedra. The crystal structure of the orthorhombic (n-C₅H₁₁)₄NFeI₄ (spgr Pnna; a = 20.143(4) Å; b = 12.683(3) Å; c = 12.577(3) Å) contains tetrahedral [(n-C₅H₁₁)₄N]⁺ ions and [FeI₄]^? ions, respectively.     

Rhodium(III), palladium(II) and platinum(II) complexes of Bis(o-aminobenzenesulfonyl)ethylenediamine

New complexes of the formulae K₃[RhL ₃]·2 H₂O, [PdL]·H₂O and [M(LH₂)Cl₂] [whereM = Pd, Pt andLH₂ = bis(o-aminobenzenesulfonyl)ethylenediamine] have been prepared and characterized by conductivity measurements, thermogravimetric analysis, X-ray powder patterns and IR, Ligand Field and¹H-NMR spectroscopy.

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Rhodium(III), Palladium(II)- und Platin(II)-Komplexe mit Bis(o-aminobenzolosulfonyl)ethylendiamin (Kurze Mitteilung)

Zusammenfassung Neue Komplexe der allgemeinen Formeln K₃[RhL ₃]·2H₂O, [PdL]·H₂O und [M(LH₂)Cl₂] mitM = Pd, Pt undLH₂ = Bis(o-aminobenzolosulfonyl)ethylendiamin wurden dargestellt und mit Konduktionsmessungen, thermogravimetrischen Analysen, Röntgenstrukturanalysen, IR, Ligandfeld- und¹H-NMR-Spektroskopie charakterisiert.

     

Synthese von N-phenolat-funktionalisierten Makrocyclen des 1,4,7-Trazacyclononans sowie des 1-Oxa-4,7-diazacyclononans und ihre Komplexchemie mit Eisen(III)

Synthesis of N-Phenolate-functionalized Macrocycles of 1,4,7-Triazacyclononane and of 1-Oxa-4,7-diazacyclononane and their Coordination Chemistry with Iron(III) Six new tetra- or pentadentate, N-phenolate functionalized, pendant, arm macrocyclic containing a 1,4,7-traizacyclononane or a 1-oxa-4,7-diazacyclononane backbone have been synthesized and their coordination chemistry with iron(III) has been investigated. Electronic spectra of these octahedral high-spin Fe^III complexes have been measured. The Phenolate-to-iron(III) charge transfer band has been studied as a function of the number of coordinated phenolate residues (1,2, or 3) and of the substituents at the phenolate arms. The dinuclear complex [LFe₂(μ-O₂CPh)](C1O)₄)₃ has been synthesized where the two Fe^III centres are connected via a symmetric μ-benzoato bridge and two phenolate oxygen atoms (L⁷ = N-(2-hydroxybenzyl)-1,4,7-triazacyclononane).     

Synthesis, spectral and structural studies of 1-ethoxycarbonyl-piperazine-4-carbodithioate and its Co(III), Zn(II) and Cd(II) complexes

The new complexes [Co(ecpzdtc)₃] (2) [Zn(ecpzdtc)₂(py)] (3) and [Cd(ecpzdtc)₂(py)]·H₂O (4) have been synthesized from sodium 1-ethoxycarbonyl-piperazine-4-carbodithioate [(Na⁺(ecpzdtc)⁻]. The ligand and the complexes have been characterized by elemental analyses, IR, magnetic susceptibility and single crystal X-ray data. The [Zn(ecpzdtc)₂(py)] and [Cd(ecpzdtc)₂(py)]·H₂O complexes contain pyridine as the co-ligand. [Co(ecpzdtc)₃] (2) crystallizes in the monoclinic system, whereas [Zn(ecpzdtc)₂(py)] (3) and [Cd(ecpzdtc)₂(py)]·H₂O (4) crystallize in the triclinic system. The sulfur donor sites of the bidentate ligand chelate the metal center, forming a four-membered CS₂M ring. The cobalt complex has a distorted octahedral geometry, the zinc complex is almost between trigonal bipyramidal and square pyramidal, whereas the cadmium complex is square pyramidal. The crystal structures of all the complexes are stabilized by various types of inter and intramolecular hydrogen bonding.