2,2′-Dihydroxybenzophenone thiosemicarbazone as a spectrophotometric reagent for the determination of copper,cobalt, nickel,and iron trace amounts in mixtures without previous separations

2,2′-Dihydroxybenzophenone thiosemicarbazone forms complexes with Cu(II) (λ_max = 385 nm, ? = 8.60 × 10³ liter · mol^?1 · cm^?1); Ni(II) (λ_max = 380 nm, ? = 15.4 × 10³ liter · mol^?1 · cm^?1); Co(II) (λ_max = 380 nm, ? = 12.3 × 10³ liter · mol^? · cm^?1); and Fe(III) (λ_max = 365 nm, ? = 7.9 × 10³ liter · mol^?1 · cm^?1) and have been applied to the analysis of these metal ions in binary, ternary, and quaternary mixtures. The determination procedures are based exclusively on the different pH values of the formation complexes, hence the extraction step is not necessary.     

Cobaltchelate als Hydrierkatalysatoren. II). Hydridbildung beim [Co(dmgH)2]- und [Co(dpnH)]+ -Komplex

Cobalt Chelates for Hydrogenation Catalysts. II. Hydride Formation with [Co(dmgH)₂] and [Co(dpnH)]⁺ In the presence of benzil as scavanger for the hydridocomplexes [Co(dpnH)]⁺ and [Co(dmgH)₂] the hydride formation in water/n-propanol (50% v/v) becomes the rate determining step, and the ligand hydrogenation is completely suppressed in the case of [Co(dpnH)]⁺, but only partially in the case of [Co(dmgH)₂]. The rate of hydride formation in both cases is 2^nd order with respect to the complex, and the activation parameters ([Co(dmgH)₂]: ΔH^≠ = 48.4 ± 1.0 kJ · mol–¹, ΔS^≠ = ?57.4 ± 3.4J · mol^?1 · K^?1, [Co(dpnH)]⁺: ΔH^≠ = 52.7 = 0.4 kJ · mol^?1, ΔS^≠ = ?59.8 ± 1.2J · mol^?1 · K^?1) indicate a H₂-activation by homolytic splitting for both complexes. Some sources of error and possible causes for the missing activity of [Co(tim)]²⁺ are discussed.     

Spectrophotometric study of complexes of mercury(II) with mono- and dithiosemicarbazones

The formation of complexes at pH 4.7 of the Hg(II) with five monothiosemicarbazone and two dithiosemicarbazone has been studied. The mercury(II) reacts with monothiosemicarbazones of salicylaldehyde (λ_max = 363 nm, E = 1.69 × 10⁴liters · mol^?1cm^?1), pi-colinadehyde (λ_max = 363 nm, E = 2.38 × 10⁴liters · mol^?1cm^?1), 6-methyl-picolinaldehyde (λ_max = 363 nm, E = 2.28 × 10⁴liters · mol^?1cm^?1), di-2-pyridylketone (λ_max = 380 nm, E = 2.08 × 10⁴liters · mol^?1cm^?1), and o-naphthoquinone (λ_max = 540 nm, E = 1.03 × 10⁴liters · mol^?1cm^?1) and with dithiosemicarbazones of 1,4-dihydroxyphthalimide (λ_max = 430 nm, E = 2.56 × 10⁴liters · mol^?1cm^?1) and dipyridylglyoxal (λ_max = 363 nm, E = 2.37 × 10⁴liters · mol^?1cm^?1). A critical comparison of the stoichiometry and apparent stability constant of complexes with mono- and dithiosemicarbazones is given.     

Ruthenium(III)-Phthalocyanine: Darstelllung und Eigenschaften von Di(halogeno)phthalocyaninato(1−)ruthenium(III), [Ru(X)2Pc] (X = Cl,Br, I)

Ruthenium(III) Phthalocyanines: Synthesis and Properties of Di(halo)phthalocyaninato(1?)ruthenium(III) Di(halo)phthalocyaninato(1?)ruthenium(III), [Ru(X)₂Pc^?] (X = Cl, Br, I) is prepared by oxidation of [Ru(X)₂Pc^2?]^? (Cl, Br, OH) with halogene in dichloromethane. The magnetic moment of [Ru(X)₂Pc^?] is 2,48 μ_B (X = Cl) resp. 2,56 μ_B (X = Br) in accordance with a systeme of two independent spins (low spin Ru^III and Pc^?: S = 1/2). The optical spectra of the red violet solution of [Ru(X)₂Pc^?] (Cl, Br) are typical for the Pc^? ligand with the “B” at 13.5 kK, “Q₁” at 19.3 kK and “Q₂ region” at 31.9 kK. Sytematic spectral changes within the iron group are discussed. The presence of the Pc^? ligand is confirmed by the vibrational spectra, too. Characteristic are the metal dependent bands in the m.i.r. spectra at 1 352 and 1 458 cm^?1 and the strong Raman line at 1 600 cm^?1. The antisymmetric Ru? X stretch (v_as(Ru? X)) is observed at 189 cm^?1 (X = I) resp. 234 cm^?1 (X = Br). There are two interdependent bands at 295 and 327 cm^?1 in the region expected for v_as(Ru? Cl) attributed to strong interaction of v_as(Ru? Cl) with an out-of-plane Pc^? tilting mode of the same irreducible representation. Only the symmetric Ru? Br stretch at 183 cm^?1 is selectively enhanced in the resonance-Raman(RR) spectra. The Raman line at 168 cm^?1 of the diiodo complex is assigned to loosely bound iodine. The broad band at 978 cm^?1 in the RR spectra of the dichloro complex is due to an intraconfigurational transition within the electronic ground state of low spin Ru^III split by spin orbit coupling.     

Synthesis,Structure and Magnetic Properties of Two Cobalt(II) Dicyanamide (dca) Complexes with Heterocyclic Nitrogen Donors Tetra(2‐pyridyl)pyrazine (tppz) and 2,4,6‐Tri(2‐pyridyl)‐1,3,5‐triazine (tptz): [Co2(tppz)(dca)4]·CH3CN and [Co(tptz)(dca)(H2O)](dca)

Two new transition metal dicyanamide complexes [Co₂(tppz)(dca)₄]·CH₃CN ( 1 ) [tppz=tetra(2‐pyridyl)pyrazine, dca=dicyanamide] and [Co(tptz)(dca)(H₂O)](dca) ( 2 ) [tptz=2,4,6‐tri(2‐pyridyl)‐1,3,5‐triazine] were synthesized and characterized by single crystal X‐ray diffraction analysis. In 1 each cobalt(II) atom is coordinated to three dca anions and one tppz molecule to form a distorted octahedral geometry, the neigbour two cobalt(II) atoms are bridged by one tppz ligand to form a dimer, then the cobalt(II) atoms in each dimer are joined together to form a ladder chain structure. In 2 the coordination geometry around the central metal is also distorted octahedral, each cobalt(II) atom is coordinated by two dca anions, one tptz molecule and one water ligand to form a cationic part, and the cationic part is linked with the free dca anions via the electrostatic attraction to give an infinite chain structure. Magnetic susceptibility measurement in the range of 2–300 K indicates that there are antiferromagnetic couplings between adjacent metal ions in 1 (T>29 K, (=?9.78 K, C=4.92 cm³·K·mol^?1) and ferromagnetic couplings in 2 (T>150 K, (=7.97 K, C=2.59 cm³·K·mol^?1) respectively.     

Two spin systems based on [Ni(dmit)2]− building blocks exhibiting 1-D chain and 2-D sheet structures: crystal structures and magnetic properties

The crystal structures and magnetic properties for two ion-pair complexes, [MG][Ni(dmit)₂] (1) and [RhB][Ni(dmit)₂] (2) (MG⁺ = N-(4-((4-(dimethylamino)phenyl)(phenyl)methylene)cyclohexa-2,5-dienylidene)-N-methylmethanaminium, RhB⁺ = 9-(2-carboxyphenyl)-3,6-bis(diethylamino)xanthylium; dmit^2? = 1,3-dithiole-2-thione-4,5-dithiolate), have been investigated. Complex 1 crystallizes in the monoclinic space group P2₁/c, the stacking interactions between the GM⁺ and [Ni(dmit)₂]^? lead to the anion exhibiting a banana-shaped molecular geometry; the neighboring anions form a 1-D alternating chain along the crystallographic [1 1 0] direction via intermolecular lateral-to-lateral and head-to-head S ··· S contacts. The temperature dependence of magnetic susceptibility from 2–350 K does not display the magnetic character of a 1-D chain; the magnetic susceptibility data were fit to the Curie–Weiss equation to give C = 0.351(15) emu K mol^?1, θ = ?3.51(28) K, and χ ₀ = 8.00(3) × 10^?5 emu mol^?1. Complex 2 belongs to the triclinic space group P-1 with two crystallographic inequivalent [Ni(dmit)₂]^? anions, which exhibit perfect planar geometry. Two ethyl groups of RhB⁺ are disordered over two positions at 296 K, and one becomes ordered at 150 K. The [Ni(dmit)₂]^? anions form a 2-D molecular layer via intermolecular lateral-to-lateral and head-to-lateral S ··· S interactions with the anionic layer parallel to the crystallographic (0 1 ?1) plane. The temperature variation of magnetic susceptibility from 2 to 350 K shows that antiferromagnetic coupling dominates in the anionic layer, and the disorder–order changes of cationic structure are not coupled to magnetic property.     

Synthesis and magnetic properties of binuclear cobalt(Ⅱ), nickel(Ⅱ) and copper(Ⅱ) complexes bridged by oxamidate group

Four binuclear Co(Ⅱ), Ni(Ⅱ) and Cu(Ⅱ) complexes bridged by oxamidate (oxd) group have been synthesized, namely Co2(byp)2(oxd)(ClO4)2 (1), Co2(Me2bpy)2(oxd)(ClO4)2.H2O (2), Ni2(bpy)2(oxd)(ClO4)2.2H2O (3) and Cu2(Me2bpy)2(oxd)(NO3)2 (4). (bpy=2,2'-bipyridyl, Me2-bpy=4,4'-dimethylbipyridyl, oxd=oxamidate) The complexes are characterized by IR, UV spectra, EPR and variable-temperature magnetic susceptibility (4-300 K). The susceptibility data for. complexes 1 and 3 were least-squares fit to the susceptibility equation derived from the spin Hamiltonian H=-2J . S1 . S2. The exchange integral, J, was found to be equal to -3.62 cm-1 in 1 and -1.82 cm-1 in 3. This indicates a weak antiferromagnetic spin exchange interaction between the metal ions.     

Synthesis and crystal structure of tetraethylammonium-μ-trichloro-heptachloro-diaqua-trirhenate(III)-dihydrate,NEt4[Re3Cl10(H2O)2] · 2 H2O

NEt₄[Re₃Cl₁₀(H₂O)₂] · 2 H₂O ( 1 ) was obtained from hydrochloric acid solutions of ReCl₃ and tetraethylammonium chloride, NEt₄Cl, by isothermal evaporation as dark red crystals. 1 crystallizes in the orthorhombic crystal system, space group Pnma, Z = 4, with a = 1838,7(2), b = 1456.9(1), c = 972.08(7) pm, V_m = 391.81(6) cm³ · mol^?l. The crystal structure consists of [Re₃Cl₁₀(H₂O)₂]^? anions that are arranged in the fashion of a hexagonal closest-packing of spheres. These are held together by partially disordered NEt₄⁺ cations and are bound into a hydrogen bonding system with the crystal water.     

Synthesis and characterization of a new pyrrolidine containing sulfur ligand and the transition metal complexes of Co(II), Ni(II) and Cu(I)

Potassium 1,3-dipyrrolidinopropan-2-O-xanthate (LK), and its complexes with Co(II), Ni(II) and Cu(I) have been prepared and characterized as [CoL₂(H₂O)₂]?·?2H₂O, [NiL₂(H₂O)₂] and CuL?·?2H₂O by FT-IR, ¹H and ¹³C NMR spectroscopies, elemental analyses, magnetic susceptibility and TGA techniques.     

Linear Pyrazole‐bridged Tetra(N‐heterocyclic carbene) Ligands and Their Hexanuclear Silver(I) Complexes

New hybrid ligands are reported that combine two types of popular donor groups within a single linear scaffold, viz., a central pyrazolate bridge and two appended bis(N‐heterocyclic carbene) units; the ligand strands thus provide two potentially tridentate {NCC} compartments. The pyrazole/tetraimidazolium proligands, [H₅L¹](PF₆)₄ and [H₅L²](PF₆)₄ , were synthesized via multi‐step protocols, and the NH prototropy of [H₅L¹](PF₆)₄ was examined by variable temperature (VT) NMR spectroscopy, giving solvent dependent activation parameters (ΔH^? = 27.6 kJ · mol^–1, ΔS^? = –125 J · mol^–1 · K^–1 in [D₃]MeCN; ΔH^? = 40.4 kJ · mol^–1, ΔS^? = –86.9 J · mol^–1 · K^–1 in [D₆]DMSO) that are in the range typical for pyrazoles. Reaction of the proligands with Ag₂O gave hexametallic complexes [Ag₆(L¹)₂](PF₆)₄ and [Ag₆(L²)₂](PF₆)₄ that involve all six potential donor atoms of the ligands, viz. the four C^NHC and two N^pz donors, in metal coordination. X‐ray crystallography revealed a chair‐like central {Ag₆} deck in both complexes but different arrangements of the ligand strands, which goes along with significantly different Ag^I ··· Ag^I distances that indicate more pronounced argentophilic interactions in case of [Ag₆(L¹)₂]^{4 +}.     

Sensitive spectrophotometric determination of palladium with tin(II) chlorided and rhodamine-6g after flotation

Palladium is determined by reaction with tin(II) chloride and rhordamine-6G in hydrochloric acid medium, flotation of the ion-association complex, [(R6G⁺)₂Pd (SnCl^?₃)₄]·[(R6G⁺) (SnCl^?₃] with di-isopropyl ether, and dissolution in acetone for spectrophotometry. The molar absorptivity is 2.84 x 10⁵ l mol^?1 cm^?1 at 530 nm; Beer's law is obeyed in the range 0.05–0.35 μg Pd ml^?1. Other platinum metals and silver interfere. Traces of palladium in silver metal are determined after extraction of palladium with dimethylglyoxime in chloroform.     

Preparation and Properties of trans-[CoCl2(tmd>)2]Cl,and trans- and cis-[Co(NCS)2(tmd)2]NO3 (tmd: Tetramethylenediamine)

The cobalt(III) complexes [CoX₂(tmd)₂]⁺ (X: Cl^? or NCS^?, tmd: tetramethylenediamine), in which tmd forms a seven-membered chelate ring, have been prepared. Trans-[CoCl₂(tmd)₂]Cl was derived from [Co(NO₂)₂(tmd)₂]NO₃ in a fairly good yield. Two geometrical isomers, trans and cis, of [Co(NCS)₂-(tmd)₂]NO₃ were independently synthesized from trans-[CoCl₂(tmd)₂]Cl by different methods. The geometrical configurations of the isomeric pair of the NCS complex have been determined based on chromatographic behavior, electronic absorption spectra, and vibrational spectra. The d-d and CT absorption maxima of the NCS complex (18.7 x 10³cm^?1 (ε = 275) and 30.9 x 10³cm^?1 (ε = 3630) for the trans isomer, 19.3 x 10³cm^?1 (ε = 302) and 31.0 x 10³cm^?1 (ε = 4070) for the cis isomer) and the Co-N(amine) stretching frequency of trans-[CoCl₂(tmd)₂]Cl (418 cm^?1) have been compared with those of the corresponding ethylenediamine and trimethylenediamine complexes.     

Ni(dmit)2 salts with chiral stilbazolium- and ferrocenyl-based chromophores as countercations

Four 1:1, two-component salts combining the [Ni(dmit)₂]⁻ anion (dmit²⁻ = 2-thioxo-1,3-dithiole-4,5-dithiolato) and chiral stilbazolium-based countercations (HPMS⁺ = 4′-[2-(hydroxymethyl)pyrrolidinyl]-1-methylstilbazolium and MPMS⁺ = 4′-[2-(methoxy-methyl)pyrrolidinyl]-1-methylstilbazolium), or chiral ferrocenyl-based countercations (2⁺ = (E)-1-((R)-2-methylferrocenyl)-2-(1-methyl-4-pyridiniumyl)ethene; 3⁺ = (E)-1-((S)-2-trimethylsilylferrocenyl)-2-(1-methyl-4-pyridiniumyl)ethene) were prepared. Semiconducting behaviour (2·10⁻⁴ S·cm⁻¹ measured on compressed pellets for [Ni(dmit)₂] (MPMS), for example) is secured by the presence of the [Ni(dmit)₂]⁻ anions. The chiral nature of the countercations ensures non-centrosymmetry of the structures (space group P1 for [Ni(dmit)₂](2) and [Ni(dmit)₂](3), for example). A ubiquitous antiparallel arrangement of the cations, which are thus packed in a pseudo-centrosymmetrical environment, results in almost vanishing second-order susceptibilities χ⁽²⁾, and therefore zero efficiencies in second harmonic generation.     

氢过碘酸）合银（III）配离子氧化L-脯氨酸的反应动力学及机理

L-脯氨酸独有的亚胺基使其在生物医药领域具有许多独特的功能,并广泛用作不对称有机化合物合成的有效催化剂。本文在碱性介质中研究了二（氢过碘酸）合银（III）配离子氧化 L-脯氨酸的反应。经质谱鉴定,脯氨酸氧化后的产物为脯氨酸脱羧生成的 γ-氨基丁酸盐;氧化反应对脯氨酸及Ag(III) 均为一级;二级速率常数 k′ 随 [IO₄^-] 浓度增加而减小,而与 [OHˉ] 的浓度几乎无关;推测反应机理应包括 [Ag(HIO₆)₂]^5-与 [Ag(HIO₆)(H₂O)(OH)]^2-之间的前期平衡,两种Ag（III）配离子均作为反应的活性组分,在速控步被完全去质子化的脯氨酸平行地还原,两速控步对应的活化参数为： k₁ (25 ^oC)＝1.87±0.04（mol·L^-1)^-1s^-1,∆ H₁^≠＝45±4 kJ · mol^-1, ∆ S₁^≠＝-90±13 J· K^-1·mol^-1 and k₂ (25 ^oC) ＝3.2±0.5（mol·L^-1)^-1s^-1, ∆ H₂^≠＝34±2 kJ · mol^-1, ∆ S₂^≠＝-122 ±10 J· K^-1·mol^-1。本文第一次发现 [Ag(HIO₆)₂]^5-配离子也具有氧化反应活性。     

Synthesis,structures and magnetic properties of nickel bis (dithiolene) complexes with [Fe(qsal)2]+

Two new compounds containing the possible Fe(III) spin-crossover cation, [Fe(qsal)₂]⁺ (qsalH = N-(8-quinolyl)salicylaldimine), and nickel bis(dithiolene) anions have been synthesized. Both are 1 : 1 salts [Fe(qsal)₂][Ni(dddt)₂] · CH₃CN · CH₃OH (1) and [Fe(qsal)₂][Ni(pddt)₂] (2) (dddt = 5,6-dihydro-1,4-dithiin-2,3-dithiolate; pddt = 6,7-dihydro-5H-1,4-dithiepin-2,3-dithiolate). They have been characterized by X-ray crystal structure determination, elemental analysis, UV-Vis spectra and magnetic susceptibility measurements. The UV–Vis spectra are dominated by [Ni(L)₂]^? (1, L = dddt; 2, L = pddt). Magnetic studies show antiferromagnetic interaction in 1 from intermolecular S···S contacts and π–π stacking interactions, while the antiferromagnetic interaction in 2 is very weak.     

Darstellung und Eigenschaften löslicher und Polysiloxangebundener (Ether-Phosphan)ruthenium(II)-Komplexe

Preparation and Properties of Soluble and Polysiloxane-Supported (Ether-Phosphine)ruthenium(II) Complexes Phosphine-modified Polysiloxanes of the type x SiO₂ · [SiO_3/2(CH₂)₆P(Ph)R] (x = 0 – 3, I–IV ) were prepared by hydrolytic condensation of (MeO)₃Si(CH₂)₆P(Ph)R [ 1 ; R = CH₂CH₂OMe ( a ), CH₂C₄H₇O ( b ), CH₂C₄H₇O₂ ( c ), Ph ( d )]. Crosslinking was achieved by cocondensation of 1 and Si(OEt)₄. 2 SiO₂ · [SiO_3/2(CH₂)₆P(Ph)CH₂CH₂OMe] ( IIIa ) was investigated by means of ³¹P and ²⁹Si CP-MAS-NMR-spectroscopy, especially in view of a quantification of silyl species which revealed the following ratios: T₂:T₄:Q₂:Q₃:Q₄ = 76:158:48:135:82. Reaction of RuCl₂(PPh₃)₃ with 3 moles of 1a gave fluxional RuCl₂(P∩O)(P～O)₂ ( 4a ). From its temperature dependent ³¹P{¹H}-NMR spectrum the temperatures of coalescence and the corresponding activation enthalpies could be estimated at -25°C (46 kJ · mol^?1) and +20°C (55 kJ · mol^?1). Soluble 1a-d as well as their insoluble counterparts I-IV were treated with [RuCl₂(CO)₂]_n to give all-trans-RuCl₂(CO)₂(PR₃)₂ ( 6 ). On heating (120°C) 6 could be transformed into isomeric cis, cis, trans-RuCl₂(CO)₂(PR₃)₂ ( 7 ). Decarbonylation occurred on irradiation of 6 . Polysiloxane-supported ruthenium complexes were proved to be active in the heterogeneous hydrogenation of crotonaldehyde. Thus, at p(H₂) = 50 bat, T = 120°C, reaction time = 190 min, and at a molar ratio of aldehyde: Ru = 250:1, all-trans-RuCl₂(CO)₂(P～O)₂ ( 6f , O,P = IIIa ) effected a conversion of 50%, crotyl alcohol being formed in comparatively high selectivities. Moreover, no loss of metal or ligand from the support could be observed.     

The tris(picolinate)vanadate(II) ion: Redox properties and electron transfer kinetics with cobalt(III) amines

Vanadium(II) ions form with the pyridine-2-carboxylate ligand a deep blue, tris-substituted complex absorbing at 660 nm (ε = 7.2 × 10³ M^?1) cm^?1) with a shoulder at 450 nm. Reversible spectroelectrochemistry and cyclic voltammetry were observed for this complex, with E_{$\text{1}\text{2}$} = ?0.448 V vs NHE, and ΔS_rc^θ = ?6 cal · mol^?1 · deg^?1. Electron transfer kinetics with [CO(en)₃]³⁺ led to k₁₂ = 3100 M^?1 s^?, ΔH^≠ = 12.4 kcal · mol^?1 and ΔS^≠ = ?0.9 cal · mol^?1 · deg^?1 (I = 0.10 M). For the related [Co(NH₃)₆]³⁺ complex, k₁₃ = 1.9 × 10⁴ M^?1 s^?1. The self-exchange rate constant and activation parameters were analysed in terms of relative Marcus theory.     

Ruthenium(II)-Phthalocyaninate(2–): Darstellung und Eigenschaften von Acido(carbonyl)phthalocyaninato(2–)ruthenat(II), [Ru(X)(CO)Pc2−]− (X = Cl,Br, I,NCO, NCS,N3)

Ruthenium(II) Phthalocyaninates(2–): Synthesis and Properties of (Acido)(carbonyl)phthalocyaninato(2–)ruthenate(II), [Ru(X)(CO)Pc^2?]^? (X = Cl, Br, I, NCO, NCS, N₃) (ⁿBu₄N)[Ru(OH)₂Pc^2?] is reduced in acetone with carbonmonoxid to blue-violet [Ru(H₂O)(CO)Pc^2?], which yields in tetrahydrofurane with excess (ⁿBu₄N)X acido(carbonyl)phthalocyaninato(2–)ruthenate(II), [Ru(X)(CO)Pc^2?]^? (X = Cl, Br, I, NCO, NCS, N₃) isolated as red-violet, diamagnetic (ⁿBu₄N) complex salt. The UV-Vis spectra are dominated by the typical π-π* transitions of the Pc^2? ligand at approximately 15100 (B), 28300 (Q₁) und 33500 cm^?1 (Q₂), only fairly dependent of the axial ligands. v(C? O) is observed at 1927 (X = I), 1930 (Cl, Br), 1936 (N₃, NCO) 1948 cm^?1 (NCS), v(C? N) at 2208 cm^?1 (NCO), 2093 cm^?1 (NCS) and v(N? N) at 2030 cm^?1 only in the MIR spectrum. v(Ru? C) coincides in the FIR spectrum with a deformation vibration of the Pc ligand, but is detected in the resonance Raman(RR) spectrum at 516 (X = Cl), 512 (Br), 510 (N₃), 504 (I), 499 (NCO), 498 cm^?1 (NCS). v(Ru? X) is observed in the FIR spectrum at 257 (X = Cl), 191 (Br), 166 (I), 349 (N₃), 336 (NCO) and 224 cm^?1 (NCS). Only v(Ru? I) is RR-enhanced.     

Syntheses,crystal structures,and magnetic properties of a series of double end-on azido-bridged dinuclear manganese(II) complexes

Four azido-bridged dinuclear Mn(II) complexes, [Mn₂(phen)₄ μ-₁,₁-N₃)₂][Fe^III(bpmb)(CN)₂]₂·H₂O (1), [Mn₂(phen)₄(μ-₁,₁-N₃)₂][Fe^III(bpClb)(CN)₂]₂·H₂O (2), and [Mn₂(phen)₄(μ-₁,₁-N₃)₂][M^III(bpdmb)(CN)₂]₂·3H₂O [M = Fe (3) or Cr (4); phen = 1,10-phenanthroline, bpmb^2– = 1,2-bis(pyridine-2-carboxamido)-4-methyl-benzenate, bpClb^2– = 1,2-bis(pyridine-2-carboxamido) 4-chloro-benzenate, bpdmb^2– = 1,2-bis(pyridine-2-carboxamido)-4,5-dimethyl-benzenate], have been synthesized using the synthetic strategy of large anion inducement. Single-crystal X-ray diffraction analysis reveals that all four complexes are doubly end-on (EO) azido-bridged binuclear Mn(II) complexes with two large [M(L)(CN)₂]^– (L = bpmb^2?, bpClb^2?, or bpdmb^2?) building blocks acting as charge-compensating anions. The magnetic properties of the complexes have been investigated, and the results indicate that the magnetic coupling between two Mn(II) centers through the EO azide bridges is ferromagnetic, with J = 0.64(1) cm^?1 for 1, 0.43(1) cm^?1 for 2, 0.50(1) cm^?1 for 3, and 0.66(2) cm^?1 for 4. The magneto-structural relationships of EO azido-bridged Mn(II) systems are discussed.     

CrIII-Phthalocyaninate: Darstellung und spektroskopische Eigenschaften von Di(halogeno)phthalocyaninatochromaten(III)

Cr^III Phthalocyaninates: Synthesis and Spectroscopical Properties of Di(halo)phthalocyaninato(2 –)chromates(III) [Cr(H₂O)₂Pc^2?]⁺ reacts in acetone with (ⁿBu₄N)X to yield less soluble tetra(n-butyl)ammonium di(halo)phthalocyaninato(2 –)chromate(III), (ⁿBu₄N)[Cr(X)₂Pc^2?] (X = F, Cl, Br, I). In the differential pulse voltammograms the first ring oxidation is observed at 0,80 V, the ring reduction at ?1,48 V and the metal reduction (Cr(III)/Cr(II)) at ?0,80 V (averaged potentials). The last is followed by a partial dissociation of one of the halo ligands. In the UV-VIS-NIR spectra there are three weakly absorbing spin-allowed trip-quarter(TQ) transitions (TQ1 (8,4) < TQ2 (11,5) < TQ3 (20,6); averaged values (av) in 10³ cm^?1), a (Pc + X)-CrCT transition (31,3; av in 10³ cm^?1) and the characteristic π-π* transitions of the Pc^2? ligand (B (14,5) < Q₁ (24,5) < Q₂ (29,2) < N (36,0) < L (41,0); av in 10³ cm^?1). Q₁ and (Pc + X)-CrCT depend strongly on the halo ligands. Prominent luminescence spectra are obtained by excitation within the TQ1 region, in which the spin-forbidden trip-sextet transition (8330 (X = F), 7680 (Cl), 7460 (Br) 7450 cm^?1 (I)) dominates at low temperatures (T < 50 K). The vibrational spectra are discussed. In coincidence of the excitation lines with TQ3, v_s(Cr? X) at 458 (X = F) < 246 (Cl) < 157 (Br) < 107 cm^?1 ( I ) is selectively resonance Raman enhanced. v_as(Cr? X) is observed in the FIR spectrum at 522 (X = F) < 283/326 (Cl) < 227 (Br) < 205 cm^?1 ( I ).