Synthesis and characterization of Ru(III), Rh(III), Pt(IV) and Ir(III) thiosemicarbazone complexes

Ru(III), Rh(III), Pt(IV) and Ir(III) complexes of 2-furfural thiosemicarbazone as ligand have been synthesised. These complexes have the composition [M(ligand)₂X₂]X (M = Ru(III) Rh(III) and Ir(III) X = Cl and Br) and [Pt(ligand)₂ X₂] X₂ (X = Cl, Br and 1/2SO₄). The deprotonated ligand forms the complexes of the formulae M(ligand-H)₃ and Pt(ligand-H)₃Cl. All these complexes have been characterized by elemental analysis, magnetic measurements, electronic and infrared spectral studies. All the complexes are six-coordinate octahedral.     

&“RuNO&”6 and &“RhNO&”6 compexes with 2,2′-bipyridine and 1,10-phenanthroline

The reactions of nitrosyl halides NOX (X = Cl, Br or Br₃) and N₂O₃ with RuCl₃(H₂O)₃ and RhCl₃(H₂O)₃ in the presence of 2,2′-bipyridine and 1,10-phenanthroline results in the formation of neutral nitrosyl complexes of types Ru(NO)X₃(L-L) and Rh(NO)X₂(L-L) (L-L = 2,2′-bipyridine or 1,10-phenanthroline).     

Die Umwandlung [W6X8]X4 [W6X12]X6 (X = Cl,Br)

Transformation of [W₆X₈]X₄ + 3 X₂ = [W₆X₁₂]X₆ (X = Cl, Br) The transformation of [W₆X₈]X₄ + 3 X₂ = [W₆X₁₂]X₆ (X = Cl, Br) has been investigated by changing the relation Cl₂/Br₂ and the temperature. In this way the compounds [W₆Br_12?nCl_n]Cl_6?mBr_m are isolated. All of the products are isotypic with W₆Cl₁₈ and W₆Br₁₈. Most often n equals 6, however compounds with other relations of Cl/Br are also observed (e. g. n = 4.8) The 6 ligands standing outside of the brackets are replaced by Cl or Br. The substitution of [W₆Br₆Cl₆]Cl₆ by means of bromine leads to the cluster [W₆Br₁₂]X₆. The backward transformation of the cluster compound [W₆Br₁₂]Br₆ happens by decomposition on the thermobalance, e. g. according to Gl. (1) (See Inhaltsübersicht). By analogy [W₆Br₁₂]Cl₆ is decomposed to [W₆Br₈]Cl₂Br₂, which by treatment with conc. HCl is transformed into [W₆Br₈]Cl₄ · 2 H₂O.     

Palladium(II) and platinum(II) complexes of rhodanine and 3-methylrhodanine

Summary The following palladium(II) and platinum(ll) complexes of rhodanine (HRd) and 3-methylrhodanine (MRd) have been prepared: Pd(HRd)_1.5Cl₂, Pd(HRd)₂Br₂, Pd(HRd)₂Br₂ · 0.25 EtOH, M(MRd)₂X₂ [M = Pd, X = Cl (0.25 EtOH) or Br; M = Pt, X = Cl or Br], Pd(MRd)₃Br₂, and M(MRd)₄(ClO₄)₂ (M = Pd or Pt). The ligands are coordinated to the metal through the thiocarbonylic sulphur atom. Pd(HRd)_1.5Cl₂ has presumably a structure such as (X = Cl or Br) complexes have a trans-planar coordination. Pd(MRd)₂X₂ (X = Cl or Br) complexes arecis-planar coordinated. Pd(MRd)₃Br₂ has presumably a square coordination with two MRd molecules and two CI ionscis-coordinated in the equatorial plane, and a MRd molecule and a Cl ion weakly bonded in apical position. The M(MRd)₄(ClO₄)₂ complexes have square planar coordination.Author to whom all correspondence should be addressed.     

A versatile route to (η5-C5R5)RuL2X from allylmethylruthenium complexes

Divalent ruthenium complexes, (η⁵-C₅R₅)RuL₂X (R = H, CH₃; X = Br, Cl), are formed by thermal decomposition of (η⁵-C₅R₅)Ru(CH₃)X(η³-C₃H₅) in the presence of several neutral ligands.     

Darstellung von Nonahalogenodiplatinaten(IV), [Pt2X9]−, X  Cl,Br Spektroskopische Charakterisierung,Normalkoordinatenanalyse und Kristallstruktur von (PPN)[Pt2Br9]

Preparation of the Nonahalogenodiplatinates(IV), [Pt₂X₉]^?, X ? Cl, Br Spectroscopic Characterization, Normal Coordinate Analysis, and Crystal Structure of (PPN)[Pt₂Br₉] On heating the tetrabutylammonium salts (TBA)₂[PtX₆], with trifluoroacetic acid the nonahalogenodiplatinates(IV) (TBA)[Pt₂X₉], with X ? Cl, Br are formed. The X-ray structure determination on (PPN)[Pt₂Br₉] (orthorhombic, space group Pca2, Z = 4) shows for the anions pairs of face-sharing octahedra with nearly D_3h symmetry. The mean terminal and bridging Pt? Br bond lengths are determined to be 2.42 and 2.52 Å, respectively. The electrostatic interaction of the Pt atoms results in the Pt? Pt distance of 3.23 Å and an elongation as it has been forecasted by the MO scheme for d⁶ systems. Using the structural data a normal coordinate analysis based on a general valence force field for [Pt₂Br₉]^? has been performed, revealing a good agreement of the calculated frequencies with the bands observed in the IR and Raman spectra. The stronger bonding of the terminal as compared to the bridging ligands is shown by the valence force constants, f_a(Br₁) = 1,55 > f_d(Br_b) = 0,93 mdyn/ Å.     

CsNb3Br7S: Synthese,Struktur und Bindungsverhältnisse

CsNb₃Br₇S: Synthesis, Structure, and Bonding States The reaction of NbBr₅ with Nb, Cs and S in a sealed Nb container affords CsNb₃Br₇S at 800°C (3 days). Further on isotypic compounds of the general formula ANb₃X₇Ch with A = Rb, Cs; X = Cl, Br and Ch = S, Se are obtained. CsNb₃Br₇S crystallizes monoclinic (space group P2₁/a, Z = 2), with the lattice parameters a = 707.4(2), b = 1 888.4(4), c = 994.1(2) pm and β = 98.59(2)°. The crystal structure contains Nb₃ clusters being linked by two additional Nb? Nb bonds to form infinite chains. Adjacent chains are bridged by Cs atoms in a cubeoctahedral coordination sphere of Br atoms. Similar with Nb₃Br₈ seven electrons occupy metal—metal bonding states.     

Mixed dimethyl sulfoxide-thiocarbamic ester complexes of platinum(II) halides

Summary The platinum(II) halidecis-[Pt(DMTC)(DMSO)X₂] andcis-[Pt(DETC)(DMSO)X₂](X=Cl or Br; DMSO=dimethyl sulfoxide; DMTC=EtOSCN-Me₂; DETC=EtOSCNEt₂) adducts and the platinum(II) and palladium(II) halide adducts,trans-[M(DETC)₂X₂] (M=Pt or Pd; X=Cl or Br), have been prepared. The complexes were characterized by i.r., and¹H and¹³Cn.m.r. spectroscopy. Both DMTC and DETC coordinate through the sulphur atoms. The 1:2 DETC complexes present the usualtrans configuration, whereas the presence of DMSO favourscis geometry in the mixed species.     

Negative ion mass spectra of some classes of metal carbonyl halides

The negative-ion mass spectra at 70 eV of the compounds Re(CO)₅X (X = Cl, Br, I), Mn(CO)₅X (Br, I), Re₂(CO)₈X₂ (X = Cl, Br, I), Mn₂(CO)₈Br₂ and Rh₂(CO)₄X₂ (X = Cl, Br, I) are reported. The negative molecular ions are absent and the current is mainly transported by fragments due to the loss of carbonyl groups. In the spectra of the bimetallic compounds a rather high intensity is displayed by ionic species containing the two halide substituents. The variations in the ionic abundances are related to the change of the metal-CO bond strength, while the nature of X seems to play a minor role.     

Co-ordination compounds of diacetyldihydrazone and diacetylbis(monomethylhydrazone)

Summary Diacetyldihydrazone (DADH) forms only six-coordinate complexes with iron(II), cobalt(II), nickel(II) and zinc(II). In M(DADH)₂X₂ (M=Fe, X=Br or I; M=Co, X=I; M=Ni, X=Cl, Br or NCS) the ligand is chelating in the [M(DADH)₃]²⁺ cations, while in M(DADH)₂X₂ (M=Co, X=Cl or Br; M=Ni, X=Cl or Br) the ligand is probably bridging and bidentate. Diacetylbismonomethylhydrazone (DAMH), by contrast, forms predominantly tetrahedral complexes M(DAMH)X₂ (M=Fe or Co, X=Cl or Br; M=Ni, X=Br; M=Co, X=NCS; M=Zn, X=Cl, Br or NCS) and some octahedral complexes M(DAMH)₂X₂ (M=Co, X=NCS; M=Ni, X=Br). The i.r. spectra, electronic spectra and magnetic moments of the complexes are discussed.     

Substitution reaction of η5-cyclopentadienylruthenium(II) complexes with nitrogen,oxygen and sulfur donor ligands

The heterocycles pyridine, γ-picoline, 2,2′-bipyridine and 1,10-phenanthroline react with [(η⁵-C₅H₅)Ru(MPh₃)₂X] (M = P, As or Sb) and [(η⁵-C₅H₅)Ru(AsPh₃)(PPh₃)X] (X = Cl, Br, I, CN, NCS or SnCl₃) to form complexes of types [(η⁵-C₅H₅)(MPh₃)(L−L)⁺X⁻ (L−L = 2,2′−bipyridine or 1,10−phenanthroline; X = Cl, Br, I, CN, NCS or SnCl₃) and [(η⁵-C₅H₅)Ru(MPh₃)LX] (M = As or Sb; L = pyridine or γ-picoline; X = Cl, Br, I, CN, NCS or SnCl₃). Interactions of dithiocarbamate (DTC) with [(η⁵-C₅H₅)Ru(SbPh₃)₂X] (X = Cl, Br or I) and acetylacetonate (acac) with parent compounds [(η⁵-C₅H₅)Ru(MPh₃)₂X (M = P or Sb; X = Cl, Br or I) yielded [(η⁵-C₅H₅)Ru(MPh₃)L] (where L = DTC or acac). The reaction products have been characterized by magnetic, spectral and microanalytical data.     

Dissolution of copper and gold in the donor-acceptor systems DMSO-NH4Xaq (X = Cl, Br, and I) and NH4Iaq-O2

The dependences of the dissolution rate of copper on the ratio of components of the liquid phase (DMSO and NH₄X_aq, where NH₄X_aq is an aqueous solution of NH₄X; X = Cl, Br, and I) were studied in aqueous-organic donor-acceptor systems DMSO-NH₄X_aq systems by the resistometric method. The method involves measurements of the electroresistance of a metal sample in the course of the reaction. The pattern of the dependences observed under the conditions of free air access shows that the process rates mzximize at the molar ratio of the components NH₄X: DMSO = 0.05: 0.95 (gC = Cl, Br, and I) and minimize at the ratio 0.5: 0.5 (for gC = Cl and Br). The second maximum is detected at the ratio NH₄I: DMSO = 0.8: 0.2 for the DMSO-NH₄I_aq system. The inorganic donor-acceptor system NH₄I_aq-O₂ was found to efficiently dissolve copper and gold.     

Synproportionierung am metallischen Substrat: CsCu2Cl3 und CsCu2Br3

CsCu₂Cl₃ and CsCu₂Br₃ by Synproportionation at the Metallic Substrate CsCu₂Cl₃ and CsCu₂Br₃ are obtained as single crystals via a dry route by synproportionation of mixtures of CsX/2 CuX (X = Cl, Br) and CsCuCl₃, respectively, with the copper of the surface of a closed copper cylinder as the metallic substrate. Lattice constants of CsCu₂Cl₃ (CsCu₂Br₃) are: a = 950.75(9) (987.3(1)), b = 1189.8(2) (1235.5(2)), c = 559.92(6) (581.80(9)) pm, orthorhombic, Cmcm, Z = 4. Details of the Cs? X polyhedra (X = Cl, Br, I) and the double chains of tetrahedra [Cu₂X₃]^? in CsCu₂Cl₃, CsCu₂Br₃, and CsCu₂I₃ are compared.     

Donorstabilisierte Galliumdihalogenide Ga2X4·2D (X = Cl,Br; D = Donormolekül): Ein experimenteller Beitrag zu den Variationsmöglichkeiten der Ga‐Ga‐Einfachbindung

Donor‐stabilized Galliumdihalides Ga₂X₄·2D (X = Cl, Br; D = Donor): An Experimental Contribution on the Variation of the Gallium‐Gallium Single Bond During the disproportionation of metastable GaX‐solutions (X= Cl, Br) donor‐stabilized galliumdihalides are formed as oxidized products. According to X‐ray structure analyses they all exhibit dimeric entities DX₂Ga‐GAX₂D (D= THF, NHEt2, NEt3, 4‐^tButylpyridin or Br^‐), which means these compounds are isoelectronic with ethane and could schematically be regarded as representatives of catenulate or alkane‐like gallium subhalides: Ga_n(X, D)_2n+2. The gallium‐gallium bond in these compounds is shorter than in the organometallic compounds such as R₂Ga‐GaR₂. The comparison of the bonding situation in the galliumdihalides, particularly of the gallium‐gallium bond, shows clearly the influence by donor molecules as well as by halogen ligands.     

Structure and bonding of three-coordinate N-heterocyclic carbene nickel nitrosyl complexes: Theoretical study

The structure and bonding of the for C₃N₃H₂X₂Ni(Cp)NO (X = H, F, Cl, Br) and their linkage isomers C₃N₃H₂X₂Ni(Cp)ON has been studied by carrying out density functional theory. The bonding nature of NiC bonds has been further explored by means of AIM method and natural bond orbital (NBO) analysis. Nucleus-independent chemical shift (NICS) values calculated at several points above ring center indicate aromaticity of heterocyclic cycle. Also, the effect of substitution (X = F, Cl, Br, CN) in N-heterocyclic carbene on the properties of complex has been shown.     

Darstellung und spektroskopische Charakterisierung der Nona-halogenodiiridate(III), [Ir2X9]3−, X = Cl,Br

Preparation and Spectroscopic Characterization of Nonahalogenodiiridates(III), [Ir₂X₉]^3?, X = Cl, Br The pure nonahalogenodiiridates(III), A₃[Ir₂X₉] (A = K, Cs, tetraalkylammonium; X = Cl, Br) have been prepared. They are formed from the monomer hexahalogenoiridates(III) which are bridged to confacial bioctahedral complexes by ligand abstraction in less polar organic solvents. The IR and Raman spectra exhibit bands in three characteristic regions; at high wavenumbers stretching vibrations with terminal ligands ν(Ir?Cl_t): 360?300, ν(Ir?Br_t): 250?220; in a middle region with bridging ligands ν(Ir?Cl_b): 290?235, ν(Ir?Br_b): 205?190 cm^?1; the deformation bands are observed at distinct lower frequencies. The distance between ν(Ir?X_t) and ν(Ir?X_b) increases with decreasing size of the cations. The electronic spectra measured at thin films of the pure complex salts at 10 K show some intensive charge transfer transitions in the UV and one or two weak d? d bands in the visible region.     

Einkristall-Röntgenstrukturanalysen an Verbindungen mit kovalenter Metall—Metall-Bindung. II. Die Molekül- und Kristallstruktur von X2Sn[Mn(CO)5]2 (XCl,Br) Verbindungen

Single Crystal X-Ray Analysis of Compounds with Covalent Metal–Metal Bonds. II. Molecular and Crystal Structure of X₂Sn[Mn(CO)₅]₂ (X?Cl, Br) Both X₂Sn[Mn(CO)₅]₂ compounds (X?Cl, Br) crystallize in the monoclinic crystal system with at times different values in the lattice parameters. They belong to the space group C_2h⁵. The structures have been solved using 2 107 symmetrical independent reflection for Cl₂Sn[Mn(CO)₅]₂ and 1 470 reflections for Br₂Sn[Mn(CO)₅)₂] by applying the heavy atom method. The following interatomic distances have been found: Cl₂Sn[Mn(CO)₅]₂, Sn? Mn = 2.635(1) Å, Sn? Cl = 2.385(2) Å, Mn? C = 1.852(8) Å, C? O = 1.128(10) Å; Br₂Sn[Mn(CO)₅]₂, Sn? Mn = 2.642(3) Å, Sn? Br = 2.548(2) Å, Mn? C = 1.851(21) Å, C? O = 1.124(25) Å. In addition, bond angles of X? Sn? X and Mn? Sn? Mn of these compounds have also been estimated in the case of X = Cl: 95.80(7)° and 126.25(4)° and for X?Br: 98.44(8)° and 125.88(9)°. The individual molecules of the X₂Sn[Mn(CO)₅]₂ solids are surrounded by ligands showing distorted tetrahedral configuration at the Sn atom and distorted octahedral configuration at the Mn atom.     

Metal complexes of pyrimidine-derived ligands—IV. synthesis,characterisation and coordinating properties of two guanidino pyrimidines: Ni(II) complexes with 2-guanidino-4,6-dimethyl pyrimidine and 2-phenyl guanidino-4,6-dimethyl pyrimidine—potential ligands or biological interest

Synthesis and spectroscopic characterisation (IR, mass, PMR) of 2-guanidino 4,6-dimethyl pyrimidine (GPym) and 2-phenyl guanidino 4,6-dimethyl pyrimidine (PG-Pym) are reported. Complexation of the title ligands with nickel(II) salts in moisture-free condition furnish complex species of the type: Ni(GPym)₂X₂[X = Cl, Br, SCN and NO₃] and Ni(PGPym)₂X₂ [X = Cl, Br, I and SCN]. Physico-chemical characterisation of the complex species have been made from molar conductance data, magnetic susceptibility measurements, electronic and vibrational spectra. Magnetic and electronic spectral features suggest a pseudo-octahedral environment of the central Ni(II) ion in all these complexes. IR spectra have furnished positive information regarding the bonding sites of the ligand molecules (namely, the pyrimidyl nitrogen and the imino nitrogen of the guanidine residue) and the mode of the attachment of the counterion(X) to the metal ion.     

Die Gadoliniumcarbidhalogenide Gd4C2X3 (X = Cl,Br)

The Gadolinium Carbide Halides, Gd₄C₂X₃ (X = Cl, Br) The compounds Gd₄C₂X₃ (X = Cl, Br) and Tb₄C₂Br₃ have been prepared by reaction of the metals (RE), REX₃, and C in sealed Ta capsules at 1 100° and 1 300°C, respectively. Monophasic samples of Gd₄C₂Br₃ and Tb₄C₂Br₃ were obtained by reacting stoichiometric mixtures of the starting materials for five days. The needle shaped crystals are bronze-coloured and sensitive to air and moisture. Gd₄C₂X₃ crystallizes in the space group Pnma (No. 62) with lattice constants a = 1 059.6(4), b = 368.4(1), c = 1 962.7(8) pm (Gd₄C₂Cl₃), a = 1 084.4(1), b = 373.0(1), c = 2 036.1(1) pm (Gd₄C₂Br₃). According to Guinier photographs, Tb₄C₂Br₃ is isotypic (a = 1 074.3(2), b = 370.6(1), c = 2 019.4(1) pm). In the crystal structure C is octahedrally coordinated by Gd. The Gd₆ octahedra are linked via common edges to form corrugated layers. The X-anions coordinate all free edges and corners of these layers and connect them via Xⁱ? Xⁱ contacts parallel [001]. Gd₄C₂Br₃ shows metallic conductivity. The magnetic susceptibility follows at high temperatures a Curie Weiss law with an effective moment of 7.95 μ_B. At temperatures below 50 K antiferromagnetic order is observed.     

Preparation and synthetic utility of fluorinated phosphonium salts,bisphosphonium salts and phosphoranium salts

The synthesis and mechanism of formation of phosphonium salts of the type [R₃$\text{P}\text{+}$CFXY]Z^? (where X = F, Cl, Br; Y = Br, Cl; Z = Br, Cl), $\text{bis}$-phosphonium salts of the type [R₃$\text{P}\text{+}$CF₂$\text{P}\text{+}$R₃]2Br^?, and phosphoranium salts of the type [R₃$\text{P}\text{+}$$\text{C}\text{?}$F$\text{P}\text{+}$R₃]X^? (X = Br, Cl) will be presented. The applicability of these substrates in the generation of useful nucleophilic or electrophilic synthetic intermediates will be discussed.