bluuebunny/crossref_metadata_2025 huggingface dataset:
Sila-Pharmaka, 35. Mitt. [1] Sila-Substitution des Akarizids Fenbutatinoxid und einiger seiner Derivate: Synthese und Eigenschaften von Hexakis[(dimethylphenylsilyl)methyl]distannoxan und Tris[(dimethylphenylsilyl)methyl](1,2,4-triazoI-l-yl)stannan / Sila-Pharmaca, 35th Communication [1] Sila-Substitution of the Acaricide Fenbutatinoxide and Some of its Derivatives: Synthesis and Properties of Hexakis[(dimethylphenylsilyl)methyl]distannoxane and Tris[(dimethylphenylsilyl)methyl]1,2,4-triazol-l-yl)stannane
Authors: Tacke Reinhold , Link Matthias , Joppien Hartmut , Ernst Ludger
Published: March 2015

Starting from SnCl4. hexasila-fenbutatinoxide (2b) [a silicon analogue of the acaricide fenbutatinoxide (2b)] and its derivatives lb and 3b were prepared (SnCl4 → 1b → 2b -> 3b). The distannoxanes 2a and 2b were found to react very easily with H2O to give the corresponding stannols 4a and 4b, respectively. In solution (C6D6 or CDCl3) the equilibria 2a/2b + H2O ⇄ 2 4a/4b were observed (1H NMR). With regard to the system 2a/4a/H2O, this observation is at variance with an earlier report in which the sterically bulky neophyl substituents [C6H5(CH3)2CCH2] are said to prevent the condensation of 4a to give 2a. - 1b -3b were found to be potent acaricides showing activities similar to those of their carbon analogues 1a -3a (test organisms: adult females of Tetranychus urticae Koch)
Elementorganische Verbindungen mit ö-Phenylenresten, XI [1] 3:l-Komplexe von Hexachlor-dibenzo-p-dioxin-2,3-chinon mit 2,3,7,8-Tetramethoxythianthren und -selenanthren / Organometallic Compounds with o-Phenylene Substituents, Part XI [1] 3:1 Complexes of Hexachloro-dibenzo-p-dioxin-2,3-quinone with 2,3,7,8-Tetram ethoxythianthrene and Selenanthrene
Authors: Hinrichs Winfried , Berges Peer , Klar Günter
Published: March 2015

The title com pounds can be isolated from concentrated solutions of 2,3,7,8-tetramethoxy thianthrene or selenanthrene and tetrachloro-o-benzoquinone as dark blue crystals. Bond distances and bond and folding angles of the components indicate these com pounds to be charge transfer complexes in which the tetramethoxy thianthrene or selenanthrene molecules act as donors (D), the hexachloro-dibenzo-p-dioxin-2,3-quinone molecules as acceptors (A). In the asymmetric units of the two isostructural complexes an acceptor, a donor and another acceptor molecule are arranged parallel to each other. A third acceptor molecule is placed at the front side of the A1 ,D ,A2-arrangement. In the crystal the A1, D, A2,(A3) units are connected by centres of symmetry leading to A1 ,D ,A2 , A1',D',A2', . . . stacks in which the aryl rings of the halves of the molecules are equidistant and parallel to each other. The mean distances between the rings are 340 and 345 pm, respectively
Über Erdalkalimetallverbindungen des 1,1-Dicyanoethylen-2,2-dithiolats, III+ Die Kristallstruktur von SrS2C4N2 · 5 H2O / On Alkaline-Earth Metal Compounds of 1 ,1-Dicyanoethylene-2 ,2 -dithiolate, III+ Crystal Structure of SrS2C4N2 · 5 H2O
Authors: Hummel Hans-U. , Wolf C.
Published: March 2015

By reaction of CS2 with maleonitrile in presence of sodiumethanolate in ethanol, Na2S2C4N2 is obtained. SrS2C4N2 · 5 H2O was synthesized by reaction of Sr(NCS)2 with Na2S2C4N2 in ethanol. It crystallizes monoclinically, space group P21/c, with a = 9.201(2), b = 9.990(6), c = 14.605(5) Å, β = 122.3(3)°, Z = 4. The compound is isotypical with CaS2C4N2 · 5 H2O. A structural model based on equivalent metal positions was refined to R = 0.057. The crystal structure contains layers of nearly planar [S2C = C(CN)2]2- anions held together by interspersed Sr2+ cations in a tricapped trigonal prismatic surrounding of 6O and 3N atoms. The S atoms of the ligand are not included in the coordination sphere of Sr2+ but are involved in several O - H···S hydrogen bonds.
Kubische Cyanomercurate NR4MHg(CN)4 (R = Et, Pr; M = Li, Na, K, Cu) mit Alumosilikatstruktur/On Cubic Cyanomercurates NR4MHg(CN)4 (R = Et, Pr; M = Li, Na, K, Cu) with Alumosilicate Type Structure
Authors: Thiele Gerhard , Großmann Joachim , Pürzer Albert Wolfgang
Published: March 2015

Quaternary Cyanomercurates NR4
+[MHg(CN)4]- with R = Et, Pr; M = Li, Na, K, Cu, obtained by reactions of NR4CN . MCN and Hg(CN)2 in polar solvents, are dimorphous. The low temperature modifications are tetragonal with a space group I4̄, the high temperature forms are cubic with the space group F4̄3m . Reversible phase transitions were studied by DSC, Raman spectroscopy and X-ray diffraction. They are of first order and of displacive character. The X-ray structure determinations of the cubic forms of NEt4MHg(CN)4 with M = Na, Li showed tetra­hedral M (NC)4- and Hg(CN)4- groups connected by linear M -NC -Hg bridges to give three-dimensional frameworks o f a cristobalite type structure and with cavaties, in which the NEt4
+ cations are located.
Tribromide Salts of the Organic Donor Tetra(methylthio)tetrathiafulvalene, [TTM-TTF]+(Br3
-) and [TTM-TTF]2+(Br3
-)2
Authors: Endres Helmut
Published: March 2015

The 1:1 and 1:2 phases (TTM -TTF)Br3 and (TTM -TTF)(Br3)2, TTM -TTF = tetra(methylthio)tetrathiafulvalene, C10H12S8, have been crystallized by diffusion of bromine vapour into solutions of the donor. The 1:1 salt is monoclinic, P 21/n, a = 7.587(2), b = 11.424(3), c = 23.145(8) Å , β = 95.80(3)°, V = 1997 Å3, Z = 4, Mr = 628.45, dc = 2.09 g cm-3, final Rw = 0.028 for 912 reflections. The 1:2 salt is monoclinic, C2/m, a = 11.510(3), b = 17.039(4), c = 9.770(3), β = 141.62(1)°, V = 1190 Å3, Z = 2, Mr = 868.16, dc = 2.42 g cm-3, final Rw = 0.029 for 899 reflections. Diadic stacks of the monopositive donor cations are found in the 1:1 salt, whereas the dipositive cations in the 1:2 salt form sheets via short intermolecular S···S contacts. A relation between bond lengths and charge is indicated.
Über Antimon-haltige Heterocyclen, V Antimon(III)-dithiolate mit verbrückten 5-und 8-Ringen/On Heterocyclic Systems Containing Antimony, V Antimony(III) Dithiolates with Bridged 5-and 8 -Membered Rings
Authors: Hoffmann Harald M. , Dräger Martin
Published: March 2015

For diamony(III)-trisdithiolates two constitutions (bicyclic B or two bridged monocycles C) are possible. Two synthetical paths to three examples Sb2(XS2)3 with X = CH2CH2 (1), CH2CH2- O - CH2CH2 (2), CH2CH2- S - CH2CH2 (3) are reported. 13C NMR spectra in CDCl3 solution show the constitution C for 2 and 3, and a possible equilibrium C ⇌ 4:1) for 1. This corresponds to the result of a crystal structure analysis (R = 0.027). The constitution C found in solid 1 exhibits expanded coordination polyhedra around the two antimony atoms which indicate a starting point for rearrangement into the constitution B. The two bridged 5-membered rings have different conformations: envelope and half-chair.
Erdalkaliquadratate, I BaC4O4 · 3H2O / Alkaline-earth Squarates, I BaC4O4 · 3H2O
Authors: Robl Christian , Weiss Armin
Published: March 2015

BaC4O4-3H2O was prepared by crystallization in aqueous silica gel. The crystal structure is a complicated three-dimensional framework. Ba2+ has CN 8+1. It is surrounded by 5 water molecules and 4 Osquarate atoms (Ba-O distances from 271.1 to 324.2 pm). The squarate dianion is almost planar and shows C -C and C-O bond lengths indicating the existence of resonance stabilization, although one Osquarate atom is not connected to Ba2+ at all. Short water-Osquarate distances hint to strong hydrogen bonding which obviously plays an important part in this structure.
Übergangsmetallkomplexe mit Schwefelliganden, XXIII* Gekoppelte Alkylierungs-, Redox- und Substitutionsreaktionen an Metall-Schwefel-Zentren: Reaktionen von [Ru(PPh3)2dttd] mit Aziden RN3 und NEt4CN in CH2Cl2(dttd2-=2,3;8,9-Dibenzo-1,4,7,10-tetrathiadecan(-2); R=NEt4
+, [C(NH2)(NMe2)2]+, H+, Me3Si-) / Transition Metal Complex with Sulfur Ligands, XXIII*Coupled Alkylation, Redox and Substitution Reactions at Metal Sulfur Centers:Reactions of [Ru(PPh3)2dtt] with Azides RN3 and NEt4CN in CH2Cl2 (dttd2-=2,3;8,9-dibenzo-1,4,7,10-tetrathiadecane(-2); R=NEt4
+, [C(NH2)(NMe2)2]+, H+, Me3Si-)
Authors: Sellmann Dieter , Waeber Michael , Binder Herbert , Boese Roland
Published: March 2015

At the transition metal sulfur center of [Ru(PPh3)2dttd], (dud2- = 2,3;8,9-dibenzo-1,4,7,10- tetrathiadecane( -2)), the substitution of one PPh3 ligand by anions like N3
- or CN- in CH2Cl2 is always coupled with a chloromethylation of one thiolato S atom in dttd2- yielding the [dttd-CH2Cl]- ligand; with N3
- conversion of azido into cyano ligands takes place additionally. In the reaction of [Ru(PPh3)2dttd] with covalent azides like Me3SiN3 or HN3, the PPh3 substitution is also coupled with the oxidation of Ru(II) to Ru(III). Thus [Ru(PPh3)2dttd] on reaction with NEt4N3 or NEt4CN in boiling CH2Cl2 yields [Ru(PPh3)(L)(dttd-CH2Cl)], (L = N3
-, CN-), whereas with Me3SiN3 or HN3 in addition to [Ru(PPh3)(N3)(dttd-CH2Cl)] the paramagnetic (μeff = 1.58 B.M.) [Ru(PPh3)(N3)(dttd)] is obtained. The very stable [Ru(PPh3)(CN)(dttd-CH2Cl)] forms deeply coloured adducts with H+ as well as [CrCl3(THF)3], AlCl3 and BF3. With Mel it yields [Ru(PPh3)(CN)(Me-dttd-CH2Cl)]I. All compounds have been characterized by elemental analysis as well as spectroscopic means including ESCA; the structure of [Ru(PPh3)(CN)(dttd-CH2Cl)] has been solved by X-ray structure analysis.
An Alternative to the Mixed Probe Method in DNA Hybridization: Synthetic "lure" Nucleotide for the Ambiguous Position of Codons
Authors: Fukuda Tsunehiko , Hamana Takumi , Kikuchi Kaeko , Marumoto Ryuji
Published: March 2015

Two deoxynucleoside analogues, 1-(2-deoxy-β-D-ribofuranosyl)-2-oxo-4-imidazoline-4-carbox-amide (1) and 5-carbamoyl-2′-deoxyuridine (2), were synthesized and incorporated into decamer deoxynucleotides, which were hybridized to their complementary strands. The duplices in which 1 paired with A or G showed higher melting temperatures (Tm's) than those containing G -T or A -C mismatch, although lower than the Tm of intact totally complementary duplex. The incor­poration of 2 into a strand resulted in extreme destabilization of the duplex.
Aminations with O-Diphenylphosphinylhydroxylamine A Critical Evaluation
Authors: Sosnovsky George , Purgstaller Klaus
Published: March 2015

A critical evaluation is presented of the scope of amination reactions with O-diphenylphosphinylhydroxylamine (ODPH) as compared to those using hydroxylamine-O-sulfonic acid (HOSA). Aminations with ODPH of isopropyl, t-butyl and cyclohexyl carbanions derived from the corresponding Grignard reagents, gave the corresponding amines in 36, 34 and 50 percent yields, respectively. The amination with HOSA of the same carbanions under similar conditions was unsuccessful. The aminative quarternization of the tertiary nitrogen of pyridine and quinoline with ODPH proceeded with comparable yields to those obtained with HOSA. An improved one flask amination with ODPH of indole, skatole and carbazole was achieved in 52-62 percent yields. The amination under the same conditions using HOSA gave consistently lower yields. Several other amination reactions which have been reported for HOSA were unsuccessful using ODPH. The conclusion is reached that overall the ODPH reagent is much less versatile than HOSA. Nevertheless, in the aminations of NH groups of heterocyclic compounds ODPH appears to be superior to HOSA and is the reagent of choice, in particular, since the preparation of ODPH is much less harzardous than that of HOSA.
Notizen: The Synthesis and Crystal Structure of (R *,R *)-(±)-[(η5-C5H5){1,2-C6H4(PMePh)2}Fe(PCl3)]Cl ··2 MeCN
Authors: Hey Evamarie , Wild S. Bruce , Bott Simon G. , Atwood Jerry L.
Published: March 2015

The unit cell of (R*,R*)-(±)-[(η5-C5H5){1.2-C6H4(PMePh)2}Fe(PCl3)]Cl · 2 MeCN is orthorhombic, space group Pccn, with a = 1531.2(3). b = 2202.7(20). c = 1874.6(16) pm, and Z = 8. The salt crystallizes as a racemic compound with four pairs of asymmetric cations of opposite helicity and associated anions and solvent molecules in each unit cell.
Synthese und Struktur von Graphit-Einlagerungsverbindungen des Quecksilber(II)-chlorids / Synthesis and Structure of the Graphite Intercalation Compounds of Mercuric Chloride
Authors: Behrens Peter , Alidoosti Mehdi , Schulz Frank , Metz Wolfgang
Published: March 2015

Graphite intercalation compounds (GICs) of mercuric chloride have been synthesized by four different methods: via the vapour phase, from melts of pure HgCl2, from melts of HgCl2, and alkali metal chlorides, and from solutions in concentrated aqueous HCl. Compounds of stages 4, 3 and 2 were obtained, respectively. GICs prepared from solution always show staging disorder. Pure stage compounds of stage three and four exhibit the following repeat distances along the c⃗ axis: c(3) = 1632 pm; c(4) = 1968 pm. Further structural analysis is hindered by the disorder phenomena common to GICs. Rather surprisingly, monochromatic Laue photographs probing the in-plane order of the intercalate reveal that - regardless of the preparation method - the diffraction patterns of all compounds are identical. The main phase possesses a monoclinic in-plane lattice with cell dimensions: a = 390(4) pm, b = 412(4) pm, γ = 108.6(3)°. A structure which resembles certain features of the structure of pristine HgCl2 is proposed for this phase. Another unidentified phase seems to stabilize this structure in spite of different amounts of chlorine excess probably occurring in compounds prepared in different ways.
Synthese neuer optisch aktiver Rh-Komplexe: Die Kristallstruktur von [(5S)-3,4-Bis(diphenylphosphino)-5-menthoxy-2(5H)-furanon](1,5-cyclooctadien)rhodium-hexafluorophosphat / Synthesis of New Optically Active Rh-Complexes: The Crystal Structure of [(5S)-3,4-Bis(diphenylphosphino)-5-menthoxy-2(5 H)-furanone](1,5-cyclooctadiene)rhodium-hexafluorophosphate
Authors: Fenske Dieter , Merzweiler Kurt
Published: March 2015

The chiral diphosphine 1 reacts with [(diolefin)Rh(THF)2]PF6 (diolefine: 1.5-cyclooctadiene, norbornadiene) to form the complexes 4 and 5. The structure of 4 was determined by single crystal X-ray analysis. 4 crystallizes in the monoclinic space group P21. The lattice constants (at 180 K) are: a = 974.0(6); b = 3889.2(29); c = 1309.4(5) pm; β = 105.25(4)°. The hydrogenation of methyl-α-acetamidocinnamate in the presence of 5 yields (R)-N-acetylphenylalanine methyl ester with 33% enantiomeric excess.
Notizen: Nukleophile Addition von Alkoxid an einen kationischen Ruthenium-Schwefeldioxid-Komplex [1] / Nucleophilic Addition of Alkoxide to a Cationic Ruthenium Sulfur Dioxide Complex [1]
Authors: Schenk Wolfdieter A. , Karl Ute
Published: March 2015

The complex [C5Me5Ru(PMe3)2(SO2)]+ is susceptible to nucleophilic attack at sulfur as shown by the reaction with ROH/Na2CO3 (R = Me, Et, i-Pr) which gives the metallosulfonic esters [C5Me5Ru(PMe3)2(SO2OR)].
Cyclopentadienyldifluorphosphin und Homologe als Liganden in cis-Dichloroplatin(II)-Komplexen — Struktur von cis-(C5Me5PF2)2PtCl2 und cis-(C9H7PF2)[(C9H7)3P]PtCl2 (C5Me5 = Pentamethylcyclopentadienyl, C9H7 = Indenyl) / Cyclopentadienyldifluorophosphine and its Homologues as Ligands in cis-Dichloroplatinum(II) Complexes — Structure of cis-(C5Me5PF2)2PtCl2 and cis-(C9H7PF2)[(C9H7)3P]PtCl2 (C5Me5 = Pentamethylcyclopentadienyl, C9H7 = Indenyl)
Authors: Heuer Lutz , Bode Ulrike K. , Jones Peter G. , Schmutzler Reinhard
Published: March 2015

Derivatives of cyclopentadienyldifluorophosphine. e. g. CpPF2 (1), Cp*PF2 (Cp* = C5Me5) (2),1-(indenyl)PF2 (3), 9-(fluorenyl)PF2 (4), 1-(ferrocenyl)PF2 (5), 1,1′-(ferrocenyl)(PF2)2 (6) and also 1-N-phenyl-2-difluorophosphinopyrrole (7) were prepared using the reaction of the appropriate organolithium compound and PF2Cl. Their reactivity towards cis-dichloro-(η4-cyclooctadiene)-platinum(II) and tetracyanoethylene was investigated. The complexes poly-dichloro-bis-(cyclopentadienyldifluorophosphine)platinum(II) (8), cis-dichloro-bis-(pentamethylcyclopentadienyldifluorophosphine)platinum(II) (9), cis-dichloro-(3-indenyldifluorophosphine)(di(1-indenyl)-3-indenylphosphine)platinum(II) (10), cis-dichloro-bis-(9-fluorenyldifluorophosphine)platinum(II) (11) and cis-dichloro-bis-(1-N-phenyl-2-difluorophosphinopyrrole)platinum(II) (12) were prepared. 10 is the first mixed organodifluorophosphine-triarylphosphine-platinum(II)-complex. The structures of 9 and 10 were determined by X-ray crystal structure analyses. 9 crystallizes in the monoclinic space group, P21/c with cell constants a = 835.3(2), b = 1479.0(3), c = 2071.7(4) pm, β = 99.67(2)° and Z = 4; R = 0.038 for 4760 unique observed reflections. The bonds to platinum are all short; Pt—P 220.3, 219.8(1), Pt—Cl 231.7, 231.9(2) pm. 10 crystallizes as a toluene hemisolvate in the monoclinic space group, P21/n, with cell constants a = 1225.7(5), b = 995.0(3), c = 2886.3(10) pm, β = 90.83° and Z = 4; R = 0.074 for 2664 unique observed reflections. The precision was poor, but the unexpected presence of both 1- and 3-indenyl groups was unambiguously demonstrated.
Notizen: Darstellung und Kristallstruktur von [H3N(CH2)3NH3]SbCl5 / Preparation and Crystal Structure of [H3N(CH2)3NH3]SbCl5
Authors: du Bois André , Abriel Walter
Published: March 2015

Using 293 K diffractometer intensity data, the structure of [H3N(CH2)3NH3]SbCl5 has been determined by single crystal X-ray technique and refined to a final Rw of 0.026. The colorless crystals are monoclinic (space group P21/c) with a = 10.1338(5), b = 11.4623(7), c = 11.3668(6) Å, β = 113.52(5)° and Ζ = 4. The structure contains ψ-octahedral SbCl5
2- anions. A center of symmetry connects two anions forming a (Sb2Cl10)4- unit with rather long Sb—Cl distances for the bridging Cl-atoms (2.92 and 3.68 A, respectively).
Neue Beweise über die Wechselwirkung des Vanadyl(IV)-Kations mit Nucleotiden: 31P-NMR- und IR-Messungen in Lösung / New Evidence of the Interaction of the Vanadyl(IV) Cation with Nucleotides: 31P NMR and IR Measurements in Solution
Authors: Etcheverry S. B. , Ferrer E. G. , Baran E. J.
Published: March 2015

The interaction between the VO2+ cation and a number of nucleotides has been investigated by means of 31P NMR and IR measurements in solutions. The results support and extend previous conclusions obtained from electronic spectra and confirm the central role of the phosphate groups of the nucleotides in this process. Preliminary results obtained from IR spectra of some solid vanadyl/nucleotide compounds suggest a greater complexity of the metal-to ligand interaction in the solid state.
Radiation Induced Br-Transfer from Ethylbromide to Triethylsilane
Authors: Lugovoi Yu. M. , Getoff N.
Published: March 2015

The radiolysis of deoxygenated triethylsilane (Et3SiH) was studied in the presence of various concentrations of ethylbromide (EtBr) as a function of the radiation dose. Chain reactions are leading to rather high yields of Br-containing final products, e. g. using 0.93 mol/dm3 EtBr we obtained: Gi(Et3SiBr) = 138, Gi(HBr) = 40, Gi(Br2) = 15 and Gi(Et3Si–SiEt3) = 6, in addition to small amounts of unidentified oligomers. Based on the knowledge from previous steady-state and pulse radiolysis studies of Et3SiH, a probable reaction mechanism is postulated to allow explanation of the present results.
New Boron-Nitrogen Analogues of Uracil Derivatives [1]
Authors: Komorowski Ludwik , Niedenzu Kurt
Published: March 2015

The reaction of Ν,N′-dimethylurea with 1,5-dimethyl-2,4-bis-(dimethylamino)-1,5-diaza-2,4-dibora-3-oxacyclohexan-6-one (2) in the melt proceeds with condensation of the urea to yield two major products: the acid 1,3,5-trimethyl-2-hydroxy-1,3,5-triaza-2-boracyclohexa-4,5-dione (la); and a mixture of the methylammonium (4 a) and dimethylammonium salt (4b) of the anion [{CH3N(u-CONCH3)2}2B]-. Analogous products were obtained from the reaction of 2 with Ν,Ν′,N″-triorganylbiurets. The 2-hydroxy derivatives of type 1 form 1:1 molar adducts with amines (3) of variable thermal stability. The anhydride of la was obtained as the bis(dimethylamine) adduct [CH3N(μ-CONCH3)2B]2O · 2 (CH3)2NH (6) from the reaction of [(CH3)2N]2BOB[N(CH3)2]2 with N,N′,N″-trimethylbiuret.
Circulardichroismusuntersuchungen von Polyalkohol- und Zucker-Vanadat(V)-Komplexen / Circular Dichroism Studies of Polyalcohol and Sugar Vanadate(V) Complexes
Authors: Bauer Hermann , Brun Jeanine , Hernanto Alexius R. , Voelter Wolfgang , Paraskewas Spyridon
Published: March 2015

The complexes of tetravanadate ions with optically active polyols and carbohydrates with suitable steric properties show up to four separate cotton effects in the wavelength range of λ = 200-350 nm. Thus it is possible to classify pyranoses into four groups according to their circular dichroitic behaviour and determine the configuration and the conformation of the hydroxyl groups attached to the pyranose ring.
Synthesen und Kristallstrukturen der Kronenether-Komplexe (18-Krone-6) · 2CH3CN, [Na-15-Krone-5][ReO4] · CH3CN und [Na-15-Krone-5]PF6 / Syntheses and Crystal Structures of the Crown Ether Complexes (18-Crown-6) · 2 CH3CN, [Na-15-Crown-5][ReO4] · CH3CN, and [Na-15-Crown-5]PF6
Authors: Weller Frank , Borgholte Harald , Stenger Harald , Vogler Stefan , Dehnicke Kurt
Published: March 2015

Single crystals of (18-crown-6) · 2 CH3CN were obtained by cooling a solution of 18-crown-6 in acetonitrile to 4 °C. Space group P21/n, Z = 2, 629 observed independent reflexions, R = 0.062. Lattice dimensions at 19°C: a = 911.7(1), b = 852.0(1), c = 1370.0(2) pm; β = 104.61(1)°. The compound forms a molecular structure with approximate D3d symmetry of the crown ether molecule, and C—H ··· O interactions of the acetonitrile molecules with the crown ether, the Η···Ο distances being 243, 253, and 267 pm, respectively.

[Na-15-crown-5][ReO4] · CH3CN is formed as a by-product of the reaction of ReNCl4 with sodium fluoride in acetonitrile in the presence of 15-crown-5 and traces of water. Space group Ρ 1̄ , Ζ = 2, 3107 observed independent reflexions, R = 0.045. Lattice dimensions at 19°C: a = 823.4(1), b = 1078.8(1), c = 1204.0(1) pm; α = 112.40(1)°, β = 94.35(1)°, γ = 104.63(1)°. The compound forms ion pairs, in which the sodium atom is sixfold coordinated by the five oxygen atoms of the crown ether molecule, as well as by one oxygen atom of the ReO4- ion, which is only slightly distorted. The bond length Na—OReO3 is 237.8(8) pm, the bond angle NaORe is 164.3(5)°.

[Na-15-crown-5]PF6 is formed in the reaction of [ReCl3(NSCl)2 · POC13] with sodium fluoride in acetonitrile solution in the presence of 15-crown-5. Space group Pna21, Ζ = 4, 1130 observed independent reflexions, R = 0.123. The high R value is due to disorder of the skeletal atoms of the crown ether molecule. The compound forms ion pairs, in which the sodium atom is sevenfold coordinated by the five oxygen atoms of the crown ether molecule, as well as by two fluorine atoms of the PF6
- ion with Na—F bond lengths of 240(2), and 246(2) pm, respectively.
P—Η-funktionelle Zirkonocen-Phosphido-Komplexe und Struktur eines Diazoalkan-Insertionsprodukts / P—H Functionalized Zirconocene Phosphido Complexes and the Crystal Structure of a Diazoalkane Insertion Product
Authors: Hey Evamarie , Müller Ulrich
Published: March 2015

The reaction of Cp2ZrCl2 with [Li(THF)2PHMes]n(1) Mes = 2,4,6-Me3–C6H2) at –78°C yields Cp2Zr(PHMes)(X), with X = Cl (2) (1:1 reaction), X = PHMes (3) (1:2 reaction). Although 2 and 3 could not be obtained in a pure state, NMR spectroscopic investigations confirm the proposed formulae. 2 reacts with diphenyldiazomethane at ambient temperature with insertion of the N2CPh2 molecule into the Zr–P bond and formation of [xxx] (4). An X-ray structure determination of 4 shows the η2-bonding mode of the phosphinohydrazonido(1–) ligand to the Zr atom (Zr–N(1) 2.181(6) A; Zr–N(2) 2.205(6) A). Crystal data: space group P21/n, Z = 4, (2581 observed independent reflexions, R = 0.063). Cell dimensions (19°C): a = 11.820(2), b = 18.361(2), c = 13.758(2) Å, β = 103.86(2)°.
Ein neuer Weg zu cyclopentadienyl-substituierten Diethylaminocarbin-Komplexen des Wolframs / A New Route to Cyclopentadienyl-Substituted Diethylaminocarbyne Complexes of Tungsten
Authors: Filippou Alexander Constantin , Grünleitner Walter
Published: March 2015

We have developed a new, large scale, high yield synthesis of cyclopentadienyl-substituted tungsten diethylaminocarbyne complexes. In the first step an almost quantitative conversion of (η5-C5H5)W(CO)3I (1) and (η5-C5Me5)W(CO)3I (2) using EtNC and Me3NO occurs to give an isomeric mixture of cis and trans (η5-C5H5)W(CO)2(EtNC)I (3 a, 3b) and cis and trans (η5-C5Me5)W(CO)2(EtNC)I (4a, 4b), respectively. The isomeric mixtures of 3a and 3b and 4a and 4b are then quantitatively transformed with sodium powder in THF into the highly reactive, anionic isocyanide complexes Na[η(5-C5H5)W(CO)2(EtNC)] (5) and Na[(η5-C5Me5)W(CO)2(EtNC)] (6). Finally, alkylation of the strong nucleophiles 5 and 6 with Et3OBF4 occurs on the isocyanide nitrogen and yields the low-valent tungsten diethylaminocarbyne complexes (η5-C5H5)(CO)2W≡CNEt2 (7) and (η5-C5Me5)(CO)2W≡CNEt2 (8). Oxidative decarbonylation of 7 and 8 with iodine in CH2C12 gives the high-valent tungsten compounds (η5-C5H5)(I)2(CO)W≡CNEt2 (9) and (η5-C5Me5)(I)2(CO)W≡CNEt2 (10). 9 and 10 are subsequently converted with one equivalent of EtNC and TlPF6 into the cationic carbyne complexes [(η5-C5H5)(I)(EtNC)(CO)W≡CNEt2]PF6 (11) and [(η5-C5Me5)(I)(EtNC)(CO)W≡CNEt2]PF6 (12). Advantages of this route to low- and high-valent tungsten diethylaminocarbyne complexes are discussed in comparison to the classical Fischer procedure using the carbyne complex trans-I(CO)4W≡CNEt2 as precursor.
Komplexe mit dem (NSeMe)2--Liganden. Die Kristallstruktur von [PPh3Me][Cl5W(NSeMe)] / Complexes with the Ligand (NSeMe)2-. The Crystal Structure of [PPh3Me][Cl5W(NSeMe)]
Authors: Fenske Dieter , Frankenau Andreas , Dehnicke Kurt
Published: March 2015

[CH3CN—WCl4(NSeMe)] and [PPh3Me][Cl5W(NSeMe)] have been prepared by the reaction of Me3SiSeMe with [CH3CN—WCl4(NCl)] and [PPh3Me][WCl5(NCl)], respectively, as brown, moisture sensitive crystals which were characterized by IR spectroscopy. The crystal structure of [PPh3Me][Cl5W(NSeMe)] was determined: Space group PĪ, Z = 4, 7599 observed unique reflexions, R = 0.046. Lattice dimensions at —70°C: α = 1104.6(6), b = 1489.2(9), c = 1650.6(8) pm, α = 108.37(4)°, β = 90.71(4)°, γ = 93.83(4)°. The compound forms ions [PPh3Me]+ and [Cl5W(NSeMe)]-, in which the tungsten atoms is octahedrally coordinated by five chlorine atoms and by the nitrogen atom of the (NSeMe)2- ligand. The bond lengths WN 171.6(8), NSe 180.6(9) pm and bond angles WNSe 173.6(7)°, NSeC 98.3(5)° (in average of the two independent anions) are in agreement with the proposed formula W ≡ N—Se—Me ↔W = N = Se—Me.
Kinetics and Mechanism of Ligand Substitution in Binuclear Copper(II) Complexes as Model Compounds for Hemocyanin
Authors: Schindler Siegfried , Elias Horst , Paulus Helmut
Published: March 2015

A series of binuclear, hydroxyl-bridged copper(II) complexes 1-10 with the general formula [Cu2(LR2D2)(OH)](ClO4)2 was prepared and characterized. The mono basic, five- or sevendentate ligands HLR2D2 were obtained either by reduction of the Schiff bases derived from the condensation of 2,6-diformyl-4-methylphenol and the amines H2N – D (complex 1: D = -(CH2)2-NH2; 2: -(CH2)2-NMe2; 3: -(CH2)2-NEt2; 4: -(CH2)3-NEt2; 5: -(CH2)2-4-imidazolyl; 6: -CH2-2-pyridyl; 7: -(CH2)2-2-pyridyl) or by reacting 2,6-di-(chloromethyl)-4-methylphenol with 2-[(2-methylamino)ethyl]pyridine (complex 8), Ν,Ν,N′,N′-tetraethyldiethylenetriamine (complex 9) or bis[2-(2-pyridyl)ethyl]amine (complex 10) under HC1 elimination. The UV/VIS spectra of complexes 1-8 with two four-coordinate copper centers and of 9 and 10 with two five-coordinate copper centers are discussed. An X-ray structure analysis of complex 6 (= [Cu2(LR2D2)(OH)](ClO4)2 with R = H and D = -CH2-2-pyridyl) was carried out. 6 crystallizes in the orthorhombic space group Pbca and the two copper centers have practically co-planar, doubly O-bridged cis-N2O2 coordination geometries with one perchlorate anion being weakly coordinated to each copper. Stopped-flow spectrophotometry was used to study the kinetics of copper removal from [Cu2(LR2D2)(OH)]2+ with EDTA in the pH range 8.5-6.6 at 20 °C and I = 0.2 M (NaClO4). The reaction is first-order in both complex and EDTA, the rate law being: rate = k[complex][EDTA]total. At pH 8.0 second-order rate constants k range from 40.3 x 103 M -1s-1 (complex 6) to 3.72x 10-2 M-1s-1 (complex 9). It follows from the pH dependence of k that both species H2EDTA2- and HEDTA3- react independently with [Cu2(LR2D2)(OH)]2+, the reactivity of H2EDTA2- being considerably greater than that of HEDTA3-. The experimental facts support the operation of an associative (A) mechanism with the removal of the first copper being rate-controlling. The kinetic effects of the donor group D and substituent R are attributed to steric and/or electronic interactions.
Synthese und Charakterisierung ruthenocen- und osmocenhaltiger Hetero-Oligometallocene / Synthesis and Characterization of Hetero-Oligometallocenes Containing Ruthenocene and Osmocene
Authors: Ingram Georg , Jaitner Peter , Schwarzhans Karl Eberhard
Published: March 2015

Improved syntheses of ruthenocene (Ruc) and osmocene (Osc) are described. These lithiated metallocenes (RucLi1-3 and OscLi1-3) react with cobaltocenium-hexafluorophosphate (Coc+PF6
-) to give the corresponding oligometallocenes Coc+—RucPF6
- (1), 1,1′-(Coc+)2-Ruc(PF6)2 (2), Coc+—OscPF6
- (4), and 1,1′-(Coc+)2—Osc(PF6)2 (5). The products were characterized by IR, MS, NMR and elemental analysis.
Rh2Sb with (anti-)PbCl2-Type Structure
Authors: Jeitschko Wolfgang , Altmeyer Rainer O.
Published: March 2015

Crystals of Rh2Sb were prepared by sintering the elemental components in a NaCl/KCl flux. They crystallize in the orthorhombic space group Pnma with the lattice constants α = 572.1(1)-573.6(1) pm, b = 417.1(1)-418.1(1) pm, c = 792.8(2)-794.9(1) pm, V = 0.1892-0.1906 nm3 for the antimony- and rhodium-rich side, respectively, of the homogeneity range at 800 °C. The structure belongs to the Co2Si-branch of the (anti-)PbCl2-type. It was refined from single-crystal diffractometer data to a residual R = 0.059. The crystal chemistry of the various PbCl2-type compounds is briefly reviewed.
Zur Stereochemie von cis-Pterocarpanen – eine theoretische Studie / On the Stereochemistry of cis-Pterocarpans – a Theoretical Study
Authors: Friedrichsen Willy , Schöning Axel
Published: March 2015

Calculations (AM 1) on cis-pterocarpans are reported. The results are in agreement with experimental observations.
Reaktionen von Oxo-Rhenium(VII und V)-Verbindungen mit Thiobenzoylhydrazin. Kristall- und Molekülstrukturen von Re(NHNC(S)Ph)3 · DMF, Re(NHNC(S)Ph)3 · OPPh3 und [Re(NHNC(S)Ph)(NHNHC(S)Ph)2]Cl · 1/3 C2H5OH · 1/3 H2O / Reactions of Oxorhenium(VII and V) Complexes with Thiobenzoylhydrazine. Crystal and Molecular Structures of Re(NHNC(S)Ph)3 · DMF, Re(NHNC(S)Ph)3 · OPPh3 and [Re(NHNC(S)Ph)(NHNHC(S)Ph)2]Cl · 1/3 C2H5OH · 1/3 H2O
Authors: Möhlenkamp Alfons , Mattes Rainer
Published: March 2015

The reaction of NaReO4 with thiobenzoylhydrazine yields Re(NHNC(S)Ph)3- DMF (1). With ReOCl3(PPh3)2 thiobenzoylhydrazine reacts to give Re(NHNC(S)Ph)3 · OPPh3 (2) and in the presence of HCl to yield [Re(NHNC(S)Ph)(NHNHC(S)Ph),]Cl · 1/3 C2H5OH -1 /3 H2O (3). The structures of 1-3 have been determined. 1: monoclinic, space group P2,/c, a = 1150.1(9), b = 2050.0(9), c = 1181.0(8) pm, β = 109.62(5)°, Z = 4, 2980 reflections, R = 0.055; 2: trigonal, space group R 3, a = 1399.8(1), c = 1684.0(1) pm, Z = 3, 1419 reflections, R = 0.033; 3: monoclinic, space group P2,/c, a = 1446.8(3), b = 3220.7(5), c = 1727.1(4) pm, β = 108.42(2)°, Z = 12, 6112 reflections, R = 0.062. In 1 and 2 three N,S-chelating ligands NHNR (R = C(S)Ph) are coordinated to the central rhenium atom. The ligand structure is intermediate between a diazene and a hydrazido(2–) structure. In 3 each rhenium atom is coordinated by one NHNR and two NHNHR ligands, all N,S-chelating. The latter can be considered as protonated diazene ligands. The unit cell contains three isomeric coordination polyhedra.
Verteilung und Valenz der Kationen in Spinellsystemen mit Eisen und Chrom, I Zur Bildung von FeCr2O4 aus Fe, Fe2O3 und Cr2O3 im Vakuum / Distribution and Valence of the Cations in Spinel Systems with Iron and Chromium, IThe Formation of FeCr2O4 from Fe, Fe2O3 and Cr2O3 in Vacuum
Authors: Eggert Andreas , Riedel Erwin
Published: March 2015

The formation of FeCr2O4 from Fe, Fe2O3 and Cr2O3 in vacuum at 800°C has been investigated by X-ray diffraction and Mössbauer spectroscopy. The reaction mechanism is supposed to include a complicated redox reaction forming the intermediate ferrous components magnetite and wüstite, and then a diffusion reaction between wüstite and gas-transported Cr2O3 forming FeCr2O4.
trans-Tetraamminebis(hydrogensulfito)ruthenium(II), trans-[Ru(SO3H)2(NH3)4], a Structure with an Unexpected Rod Packing
Authors: Breitinger Dietrich K. , Breiter Roman
Published: March 2015

trans-[Ru(SO3H)2(NH3)4], monoclinic, space group P21/n, Z =2, a = 619.4(3), b = 701.8(3), c = 1068.6(6) pm, β = 96.32(3)°. In the centrosymmetric octahedral complex the two independent Ru–N bonds are equal within experimental error (average Ru–N 214.0 pm). The rather short Ru–S bonds (227.6 pm) indicate a very weak trans-influence of the – SO3H ligand. Caused by the protonation, one of the S–O bonds in the –SO3H ligand is long (161.4 pm), the other two are short (mean 148.0 pm). The complex units are linked by pairs of O-H ··· O hydrogen bonds (268.9 pm) to form rods parallel b (symmetry (b) · T), which in turn are held together by N–H ··· O bonds in a pseudo-hexagonal array. A packing coefficient of 0.76 is estimated.
Stereoselective Syntheses of α-D-Ribopyranosyl Disaccharides [1]
Authors: Dahlhoff Wilhelm V. , Schroth Gerhard , Gabor Barbara
Published: March 2015

1 → 6-, 1 → 3- and 1 → 1-linked α-D-ribopyranosyl disaccharides 2a, 2b, and 5, respectively are prepared with ≥95% stereoselectivities by reacting 3-O-acetyl-2,4-O-phenylboranediylβ-D-ribopyranosyl bromide (1) with the sodium organooxytriethylborates of 1,2:3,4-di-O-isopropylidene-α-D-galactopyranose, 1,2 : 5,6-di-O-isopropylidene-α-D-glucofuranose and with hexabutyl-distannoxane, respectively. After deboronation and deacetylation 3a, 3b, and 6 are obtained and these are acetylated to give 4a, 4b, and 7.
Derivatisierungsreagenzien für die HPLC-ECD-Analyse von Peptiden und Proteinen auf Ferrocenbasis: Synthese und Umsetzung mit H – Phe – OtBu als Eignungstest / Derivatizing Reagents to Analyse Peptides and Proteins by HPLC-ECD Based on Ferrocene: Synthesis and Reaction with H – Phe – OtBu to Test their Suitability
Authors: Eckert Heiner , Koller Marianne
Published: March 2015

We want to report on syntheses and test reactions of some ferrocenic compounds which could be used as derivatizing reagents for peptides and proteins in order to detect them electrochemically after an HPLC analysis run. Among the tested compounds we found the 3-ferrocenylpropionic anhydride as the most suitable reagent for this purpose. It is a stable compound which can be prepared with high yields from 3-ferrocenylpropionic acid. Its reaction products with peptides and proteins are highly electroactive which is essential for the sensibility and selectivity of the method.
Synthese und Kristallstruktur von MoCl4(DME) · 15-Krone-5 und MoCl4(DME) (DME = 1,2-Dimethoxyethan) / Synthesis and Crystal Structure of MoCl4(DME) · 15-Crown-5 and MoCl4(DME) (DME = 1,2-Dimethoxyethane)
Authors: Hey-Hawkins Evamarie , Schnering Hans Georg von
Published: March 2015

NaSi reacts with MoCl5 and 15-crown-5 in toluene with reduction of Mo(V) to Mo(IV). Work-up in DME yields MoCl4(DME)· 15-crown-5 (1). MoCl4(DME) (2) is prepared more conveniently from MoCl5/DME. 1 and 2 were characterized spectroscopically and by X-ray structure determination. Crystal data: 1, space group P212121 (No. 19), Z = 4, 2765 observed independent reflexions, R = 0.026, cell dimensions (110 K): a = 16.292(4), b = 12.884(3), c = 10.452(2) Å. 2, space group I4̄2d (No. 122), Z = 8, 558 observed independent reflexions, R = 0.037, cell dimensions (292 K): a = b = 9.562(2), c = 23.777(6)Å. The MoCl4(DME) molecule of 1 and 2 forms a distorted octahedron. There are four non-coordinating 15-crown-5 molecules present in the unit cell of 1. The UV/VIS spectrum and the magnetic properties of 2 are discussed.
Elektrochemische und spektroelektrochemische Untersuchungen neuer S-heterochinoider Elektronenakzeptoren, N-Cyanimin-substituierte Thieno[3,2-b]thiophen-2,5-dione / Electrochemical and Spectroelectrochemical Investigations of New S-Heteroquinoid Electron Acceptors, N-Cyanimine Substituted Thieno[3,2-b]thiophene-2,5-diones
Authors: Salbeck Josef , Günther Erhard
Published: March 2015

Redoxproperties and UV/VIS/NIR-spectra of radical anions and dianions of 3,6-dimethylthieno[3,2-b]thiophen-2,5-dion and 2,5-bis(cyanimino)-2,5-dihydro-thieno[2,3-b]thiophene derivatives are compared.
Investigation of the Hardening Reaction of Gelatin with 13C Labeled Formaldehyde by Solution and Solid State 13C NMR Spectroscopy
Authors: Albert Klaus , Bayer Ernst , Wörsching Alfred , Vögele Herbert
Published: March 2015

Model reactions of the hardening of gelatin with 13C labeled formaldehyde were monitored by 13C NMR spectroscopy in solution and in the solid state. In solution primary attack of formaldehyde first forms methylols of lysine residues and later of arginine residues, which react to a lysine-arginine crosslink. During the drying process of hardened gelatin, in addition to the lysine-arginine crosslink an arginine-arginine crosslink is formed. The rate of crosslink formation is strongly influenced by humidity.
Synthese und Eigenschaften von Tetrakis(trimethylsilylisocyanid)nickel(0), Ni(C=N—SiMe3)4 / Synthesis and Properties of Tetrakis(trimethylsilylisocyanide)nickel(0), Ni(C=N—SiMe3)4
Authors: Bessler Eberhard , Barbosa Browdo Marins , Hiller Wolfgang , Weidlein Johann
Published: March 2015

Ni(CNSiMe3)4 (Me = CH3), the first homoleptic isocyanosilane complex, has been prepared by reaction of bis(1,5-cyclooctadiene)nickel(0) with trimethylcyanosilane in ether and characterized by its infrared, Raman spectra, 13C NMR spectra.
Neue Untersuchung über Inhaltsstoffe aus Aloe- und Rhamnus-Arten, XIII [1] / A New Investigation on Constituents of Aloe and Rhamnus Species, XIII [1]
Authors: Rauwald Hans W. , Lohse Karsten , Bats Jan W.
Published: March 2015

Rhamnus purshianus D. C., 10-Hydroxyaloins A/B, Oxanthrone Glucosyls, Quinonoids, Anthranoids

The absolute configurations of the diastereomeric 10-hydroxyaloins, which may be regarded as parent structures for other naturally occurring oxanthrone-C-glucosyls, have been established as 10R, 16 R (A) and 10 S, 16 R (B) by an X-ray structure analysis of the A-octaacetyl derivative (C 16 is the anomeric glucosyl carbon atom). The determination was confirmed by CD spectroscopic comparison with the structural analogues aloins A and B, which should prove useful for making future configurational assignments within this class of compounds. A conformational analysis by the use of a molecular modeling method based on force-field calculations reveals the presence of an extra- and an intra-form, the extra-form of which is energetically preferred.
Synthese und Kristallstruktur von 2,4-Di-tert-butyl-3-pentafluorphenyl-1,2,4,3-thiadiazaboretidin / Synthesis and Crystal Structure of 2,4-Di-tert-butyl-3-pentafluorophenyl-1,2,4,3-thiadiazaboretidine
Authors: Habben Carl D. , Herbst-Irmer Regine , Noltemeyer Mathias
Published: March 2015

Sulfur-diimides react with bismethylmercapto-pentafluorophenylboranes by reductive 1,3-cycloaddition of the NSN-sequence and formation of the 1,2,4,3-thiadiazaboretidines 2a,b. NMR (1H, 11B, 13C, 19F, 29Si), mass spectra and the results of the X-ray structure analysis of 2 a are reported and discussed.
Synthese und Kristallstruktur von Triphenylmethylphosphoniumtriiodid [P(C6H5)3CH3]I3 / Synthesis and Crystal Structure of [P(C6H5)3CH3]I3
Authors: El Essawi Mervat , Abd El Khalik Sawsan , Berthold H. J. , Wartchow R.
Published: March 2015

Triphenylmethylphosphonium triiodide [P(C6H5)3CH3]I3 has been prepared by the reaction of [P(C6H5)3CH3]I with iodine in ethanol. Deep violet crystals were obtained by recrystallization from dichloromethane.

The crystal and molecular structure of the compound has been determined. The crystals are orthorhombic, space group Pbca, Z = 8, a = 1182.2(2), b = 1987.6(3), c = 1798.8(3) pm.

Least squares refinement of the structure yielded R = 0.038 (Rw = 0.030, RG = 0.030) for 2433 independent reflections.

The triodide ion I3
- is slightly asymmetrical and slightly bent. The distances are 293.7(1) pm (I(1)—I(2)) and 291.7(1) pm (I(2)—I(3)), the angle I(1)—I(2)—I(3) is 179.3(1)°.

The structure contains layers perpendicular to the c axis, which follow each other with a period of c/2 and are built up by I3
- anions and [P(C6H5)3CH3]+ cations. They are stacked to give layers of cations and layers of anions perpendicular to the b axis. The shortest I ··· I distance between I3
- ions in the anion layer occurs in the c direction. It amounts to 414 pm, thus indicating that there are only very weak I ··· I interactions between the I3
- ions. Further I ··· I contacts in the layer lie between 510 and 746 pm.
Ein 2 π-Vierring-Aromat mit stark reduzierter 1,3-Wechselwirkung / A Four-Membered 2 π Aromatic System with Strongly Reduced 1,3-Interaction
Authors: Pilz Monika , Allwohn Jürgen , Bühl Michael , Ragué Schleyer Paul von , Berndt Armin
Published: March 2015

2,4-Dicyclopropyl-1,3-diduryl-1,3-dihydro-1,3-diborete (1 e) has the most strongly deshielded ring carbon atoms (δ13C = 186.7 ppm) and the longest C 1–C3 distance (196.6(5) pm) observed so far for 1,3-dihydro-1,3-diboretes. Its folding angle along the C 1–C 3 bond, however, is only slightly reduced (δ = 45°). For the planar (α = 0) unsubstituted 1,3-dihydro-1,3-diborete (1 f′) the corresponding data are calculated by the combined ab initio/IGLO/NMR method to be δ13C = 302 ppm and C 1–C3 218.3 pm. Comparison of these data with those of 1 a and 1 b shows that the bonding 1,3-interaction in 1 e is strongly reduced.
Notizen: The Crystal Structure of MnIn2Se4, a Ternary Layered Semiconductor
Authors: Range K.-J. , Klement U. , Döll G. , Bucher E. , Baumann J. R.
Published: March 2015

Single crystals of MnIn2Se4 have been grown by the chemical vapour phase transport technique using AlCl3 as the transporting agent. The structure was refined to R = 0.064, Rw, = 0.059 for 609 reflections. MnIn2Se4 (R 3̄m, hexagonal axes a = 4.051(1), c = 39.464(2) Å, c/a = 9.74, Z = 3) crystallizes with a nearly close-packed layered structure (sequence of the Se layers ABCA|CABC|BCAB) with Moct (= 0.56 Mn + 0.44 In) in octahedral coordination (Moct,–Se = 6 × 2.721(1) A) and Mtet (= 0.78 In + 0.22 Mn) in tetrahedral coordination (Mtet-Se = 1 × 2.527(2) and 3 × 2.593(1) Å). The overall layer sequences is ΑβΒαCyA| Cα AγBβC| BγCβAα B.
Übergangsmetallkomplexe mit Schwefelliganden, LXVI / Transition Metal Complexes with Sulfur Ligands, LXVI
Authors: Sellmann Dieter , Kern Wolfgang , Holzmeier Adelgunde , Pöhlmann Georg , Moll Matthias
Published: March 2015

Since substrate addition and elimination reactions are essential reactions of metal sulfur centres in oxidoreductases, we investigated the substitution of chloride in [Mo(Cl)(NO)(′S4')](1) (′S4′2- = 1,2-Bis(2-mercaptophenylthio)ethane(2-)) [4] and in the analogous tungsten complex [W(Cl)(NO)(′S4')](2). The chloride ligands in 1 and 2 can easily be substituted by thiolates to give [M(SR)(NO)(′S4')] (M = Mo, R = Me 3a,′Pr 3b, nBu 3c, Ph 3d; M = W, R = Me 4a, Ph 4b). For these substitution reactions an associative mechanism is suggested. The SR- ligands act probably as σ-π four electron donor ligands to give metal centres with an 18 electron configuration as also found in the amido complexes [Mo(NR2)(NO)('S4')] [4]. 1 and 2 react with PMe3 to yield the adducts [M(PMe3)(Cl)(NO)('S4')] (M = Mo 5, W 6), whose NMR spectra indicate the formation of two stereoisomers in a ratio of about 2:3.
Übergangsmetallkomplexe mit Schwefelliganden, LXXII / Transition Metal Complexes with Sulfur Ligands, LXXII
Authors: Sellmann Dieter , Lechner Peter , Moll Matthias
Published: March 2015

Racemic [Ru(ClH)(PPh3)′S4'] · CH2Cl2 (′S4'2-= 1,2-bis(2-mercaptophenylthio)ethane(2—)) reacts with monodentate sulfur ligands L to yield diastereospecifically yellow adducts [Ru(L)(PPh3)′S4']. Asymmetric achiral thioethers (L = SPhMe, CH3SSCH3) give only one of two potentially possible pairs of enantiomers, chiral thioethers and thiols (L = N-Acetyl-(L)-Methionin, N-Acetyl-(L)Methionin-methylester, S-Methyl-(L)Cystein, N-Acetyl-(L)Cystein) only two of four potentially possible diastereomers in the ratio 1:1.

These results prove that the diastereospecifity is related to the coordinated thioether or thiol sulfur atom: It becomes stereogenic in the course of coordination and its configuration is determined by the chirality of the [Ru(PPh3)′S4'] fragment. Additional stereogenic centres in the substituents of chiral thioethers or thiols do not enhance the degree of diastereoselectivity.
Modeling the Transition State of Biological Phosphoester Cleavage: The Complexation of Vanadate(V) by Nucleosides
Authors: Richter Jens , Rehder Dieter
Published: March 2015

The predominant complex species formed between inosine and vanadate in aqueous media is binuclear and biligate (δ(51V) = —523 ppm; the formation constant at pH 7.9 and an ionic strength I = 1 M is K4 = 2.2(1) · 107 M-3), with essentially a pentagonal-bipyramidal geometry around vanadium, coordination through two adjacent (2′ and 3′) ribose oxygens, and dimerization via alkoxo bridges. The complexation depends upon concentration, pH, temperature, and solvent. The pH range of 7.1-8.8 has been studied. In dry dmso, the geometry of the vanadate-inosine complex is probably octahedral (δ(51V) = - 494 ppm). Adenosine (Ad) shows a behaviour very much comparable to inosine in aqueous media (K4 = 2.5(1) · 107 M-3), but higher equilibrium concentrations of a 1:2 complex (VAd2)n have been detected in this case. There is evidence (by 1H NMR) for participation of the NH, group of the base in coordination. The overall formation constant for the complexes formed between vanadate and guanosine in water amounts to ca. 24 M-1.
Selektive Additionsreaktionen an bifunktionalen neutralen Phosphenium-Ion-Komplexen / Selective Addition Reactions of Bifunctional Neutral Phosphenium Ion Complexes
Authors: Lang Heinrich , Leise Michael , Imhof Wolfgang
Published: March 2015

The reaction of bifunctional neutral phosphenium ion complexes, containing a carbon-carbon triple bond next to a phosphorus-molybdenum multiple bond, with carbenes and to carbene isolobal organometallic fragments is discussed.

So, the reaction of (R)(PhC=C)P=MoCp′(CO), (R = 2,4,6-′Bu3C6H2O; Cp′ = η5-C5H5: la; Cp′ = η5-C5Me5: 1b) with CH2,Ν2 (2) yields the three membered heterocyclic compound

(3). 3 reacts with Co2(CO)8 to afford complex

(5) in which the phenylethynyl building block is η2-side-on coordinated to a Co2(CO)6 fragment. Similar to the reaction of 1 with 2, 1 forms with Fe2(CO)9 (6), compound

(7). In 7 the PMo double bond is coordinated in a η2 fashion to the 16-electron organometallic fragment Fe(CO)4. Using an excess of 6 and a higher temperature, the phosphorus-alkynyl-carbon σ-bond is cleaved, and cluster MoCp*Fe3(CO)8η3-PR)(C≡CPh) (8) is formed.

The reaction of 1 with Cr(CO)5(THF) yields 10, a complex, in which the PhC≡C ligand is η2-coordinated to Cp′(CO)2Mo, and the Cr(CO)5 group forms a dative bond with the phosphorus atom.

All new compounds have been characterized by analytical as well as by spectroscopic data (IR, 1H, 31P, 13C NMR, MS), compound 10 by an X-ray analysis.
Ruthenium(II)-Komplexe mit dem neuen Liganden (Oxetanyl-2-methyl)diphenylphosphan / Ruthenium(II) Complexes with the Novel Ligand (Oxetanyl-2-methyl)diphenylphosphine
Authors: Lindner Ekkehard , Möckel Andrea
Published: March 2015

The new ether-phosphine ligand (oxetanyl-2-methyl)diphenylphosphine (1) with strongly basic properties is obtained by reaction of LiPPh2 with 2-chloromethyloxetane. Reaction of 1 with Cl2Ru(PPh3)3 results in the formation of the bis(chelate) complex trans-Cl2Ru(P~O)2 (2). (P∼O = η1-P-coordinated; P~O = η/2-O,P-coordinated). With CO only one Ru-O bond is cleaved to give the monocarbonylruthenium(II) complex trans-Cl2Ru(CO)(P∼O)(P~O) (3). 3 shows fluxional behaviour only at higher temperatures as demonstrated by 31P{1H} NMR spectra.