bluuebunny/crossref_metadata_2025 huggingface dataset:
YCoC and Isotypic Carbides with a New, Very Simple Structure Type
Authors: Gerss Matthias H. , Jeitschko Wolfgang
Published: March 2015

Crystal Structure, Equiatomic Ternary Rare Earth Metal Cobalt Carbides The crystal structure of the new compound YCoC was determined from X-ray powder data. It is tetragonal, space group P42/mmc, with a = 0.36500(4) nm, c = 0.68636(9) nm and Z = 2 formula units per cell. The residual for a refinement of Debye-Scherrer data is R = 0.048 for 22 structure factors and 3 variable parameters. The structure is of a new type with no variable positional parameter. The arrangement of the metal atoms corresponds to that of the CsCl structure. The tetragonal superstructure with a doubled c axis arises through the ordered insertion of carbon atoms on octahedral sites formed by four Y and two Co atoms. The hydrolysis of YCoC in hydrochloric acid yields mainly methane, propane, and ethane. The compounds LnCoC (Ln = Gd -Tm, Lu) are isotypic with YCoC.
Chemie und Strukturchemie der Phosphide und Polyphosphide, 41 Synthese, Struktur und Eigenschaften neuer silyl-, germyl- und stannylsubstituierter Heptaphosphane(3) P7(MPh3)3 mit M = Si, Ge, Sn / Chemistry and Structural Chemistry of Phosphides and Polyphosphides, 41 Synthesis, Structure and Properties of New Silyl, Germyl and Stannyl Substituted Heptaphosphanes(3) P7(MPh3)3 with M = Si, Ge, Sn
Authors: Mujica Carlos , Weber Dieter , Schnering Hans-Georg von
Published: March 2015

, 41 [1] Synthese, Struktur und Eigenschaften neuer silyl-, germyl-und stannylsubstituierter Heptaphosphane(3) P7(MPh3)3 mit M = Si, Ge, Sn Chemistry and Structural Chemistry of Phosphides and Polyphosphides, 41 [1] Synthesis, Structure and Properties of New Silyl, Germyl and Stannyl Substituted Heptaphosphanes(3) P7(MPh3)3 with M = Si, Ge, Sn Silyl-, Germyl-and Stannyl-substituted H eptaphosphanes(3), 3,5,7-T riphenylm etalla[2.2.1.02'6]hepta-phosphanes, Structures, Raman Spectra, 31P NM R Spectra New derivatives P7(M Ph3) 3 (M = Si, G e, Sn) o f the heptaphosphanortricyclen cage were synthesized by reactions o f P7(SiM e,) 3 with com pounds CIMPh,. The driving force o f the reaction is the lower solubility o f the P7(M P h,) 3 com pounds. W hereas crystals of P7(SiM e3) 3 are enan-tiom orphs, the new com pounds P7(M Ph3) 3 crystallize as racemates. With decreasing M size, the nortricyclen cage P7 is slightly twisted about the 3-fold axis. The main P -P bond lengths in the cage follow the relation A (basal) — 221.8 pm > B (basal-equatorial) = 219.0 pm > C (equato-rial-apical) = 218.5 pm. The m ean bond lengths P —Si = 228.6 and P —Ge = 234.9 and P —Sn = 253.5 pm are slightly larger than the standard single bond distances. The IR absorptions show only very small M -dependent variations in the characteristic internal cage vibrations. Similar effects are recognized in the 3,P NM R chem ical shifts.
Acetonylperoxyl Radicals, CH3COCH2O2: A Study on the y-Radiolysis and Pulse Radiolysis of Acetone in Oxygenated Aqueous Solutions
Authors: Zegota Henryk , Schuchmann Man Nien , Schulz Dorothea , Sonntag Clemens von
Published: March 2015

Hydroxyl radicals from the radiolysis of N2O/O2 (4:1)-saturated aqueous solutions of acetone (10−3 mol dm −3) react with the solute by H-abstraction thereby forming acetonyl radicals. As shown by pulse radiolysis, the acetonyl radicals rapidly add oxygen (k = 3 x 109 dm3mol−1s−1) thereby forming acetonylperoxyl radicals which decay by second-order kinetics (2 k = 8 x 108 dm3mol−1s−1). Under steady-state radiolysis conditions (0.24 Gy s−1) the products (G values in parentheses) are methylglyoxal (2.5), hydroxyacetone (0.5), form aldehyde (1 .6), acids (1 .7), carbon dioxide (0 .5), organic (hydro)peroxides (0.4), hydrogen peroxide (2 .2), and G (oxygen uptake) has been determined at 5.2. In the decay of the acetonylperoxyl radicals the major process (slightly less than one half) leads in a concerted reaction to two molecules of methyl­ glyoxal and one molecule of hydrogen peroxide. The Russell mechanism which yields one molecule of methylglyoxal, hydroxyacetone and oxygen contributes about one fifth as does the breakdown into two molecules of form aldehyde, one molecule of oxygen and two acetyl radicals. Carbon dioxide, formaldehyde and acetic acid are among the products which result from the acetylperoxyl radicals formed upon oxygen addition to the acetyl radicals. A bout one tenth of the organic peroxyl radicals is converted into hydroperoxides by O2
⨪ produced as a byproduct in the water radiolysis.
Polysulfonylamine, VIII [1] Ein Molekül mit einer extrem langen Silicium-Stickstoff-Bindung. Festkörperstrukturen von N-Trimethylsilyl- und N-Methyl-dimesylamin / Polysulfonylamines, VIII [1] A Molecule with an Extremely Long Silicon-Nitrogen Bond. Solid State Structures of N-Trimethylsilyl- and N-Methyl-dimesylamine
Authors: Schomburg Dietmar , Blaschette Armand , Wieland Elke
Published: March 2015

The crystal and molecular structures of two dimesylamine derivatives, RN(SO2CH3)2, (R = Si(CH3)3 (1a), R-CH3 (1b)) were determined. Com pound 1a displays a very long Si-N bond which is well outside the range normally found in comparable com pounds (185.1 pm, mean value for two crystallographically independent m olecules). The unusually large bond length can be explained by the absence of (d -p)π interactions between silicon and nitrogen. In both com pounds the bonding geometry around the nitrogen atoms is essentially planar
[8+2]-CycIoadditionen mit Benzylidenmalonsäurederivaten: Steuerung der Stereochemie durch die Carbonsäurestrukturteile [1] / [8+2]-C ycloadditions with Benzylidene Malonic Acid Derivatives: The Role of Carboxylic Groups in Stereoselectivity [1]
Authors: Daub Jörg , Gierisch Sebastian , Knöchel Thomas , Salbeck Erika
Published: March 2015

The stereochemistry of the regiospecific [8+2]-cycloaddition of 8 -methoxyheptafulvene (2) with Michael type olefins is elaborated. The stereoselectivities are decreasing in the series a-cyanacrylic acid ester (9), 1,1-dicyanethene derivatives (1), 5-phenylmethylene-1,3-dioxane- 4,6-dione (6 ). The mechanistic impact is discussed. The structure of the tetrahydroazulenes 3-5, 7, 8 and 10, which are formed in good chemical yields are determ ined, mainly by 1H NMR. The molecular structure of 3c is determ ined by X-ray crystallography
Spin Labeled Bovine Serum Albumin, Spin Labeled Bovine Serum Albumin Chelating Agents and Their Gadolinium Complexes. Potential Contrast Enhancing Agents for Magnetic Resonance Imaging
Authors: Sosnovsky George , Rao N. Uma Maheswara , Lukszo J. , Brasch Robert C.
Published: March 2015

Bovine Serum Albumin (BSA) was spin labeled using the active esters 3 and 5 containing a nitroxyl radical to give the spin labeled BSA derivatives 4 and 6. Spin labeled C D TA , DTPA and TTHA chelating agents 10, 13 and 16 and the corresponding BSA derivatives 17, 18 and 19 and their gadolinium complexes 20, 21 and 22 were synthesized. All these BSA derivatives were evaluated as possible contrast enhancing agents for NMR imaging by measurement of spin-lattice (T1) and spin-spin (T2) relaxations and by calculations of relaxivities i.e., slopes of 1/T1 versus concentration plots. The spin labeled BSA-complexon-gadolinium conjugates 20, 21 and 22 were found to have better relaxation times and relaxivities than the BSA spin labeled derivatives 4, 6, 17, 18 and 19. The spin count for the BSA derivatives 4, 6, 17, 18 and 19 and for their gadolinium conjugates 20, 21 and 22 was found to be between 9 -1 0 spins/molecule of the protein. The gadolinium conjugates 20, 21 and 22 of spin labeled BSA possess high relaxivities combined with a nitroxyl marker that could be used with EPR to assess pharmacokinetic behaviors of these potential contrast agents
Natural Abundance 13C—13C Coupling Constants Observed via ID and 2D INADEQUATE Experiments in Stigmasterol and 1,4-Androstadiene-3,11,17-trione
Authors: Neszmélyi Andras , Hull William E. , Lukacs Gabor , Voelter Wolfgang
Published: March 2015

For two steroids, stigmasterol and 1,4-androstadiene-3,11,17-trione, natural abundance 13C -13C coupling constants are determ ined by 1D and 2D INADEQUATE experiments. Besides full assignment of the 13C resonances of these steroids is achieved
Die Kristallstrukturen der Cyclothiazenokomplexe [MoCl3(N3S2)(Pyridin)] und [MoCl3(N3S2)(Tetrahydrofuran)] / The Crystal Structures of the Cyclothiazeno-Complexes [MoCl3(N3S2)(Pyridine)] and [MoCl3(N3S2)(Tetrahydrofurane)]
Authors: Völp Karin , Willing Wolfgang , Müller Ulrich , Dehnicke Kurt
Published: March 2015

An improved method of synthesis for MoCl3(N3S2) from molybdenum pentachloride and trithiazylchloride is given. Its reaction with pyridine and tetrahydrofuran in a CH2Cl2 suspension yields the donor-acceptor complexes [MoCl3(N3S2)(C5H5N)] and [MoCl3(N3S2)(C4H8O)], respectively. Both are soluble in CH2Cl2 and can be obtained in form of black, moisture sensitive crystals. Their IR spectra are reported and their crystal structures were determined by X-ray diffraction. Both compounds have nearly the same structure (monoclinic, space group P21/c, Z = 4). Lattice constants: [MoCl3(N3S2)(C5H5N)], a = 1102.2, b = 997.7, c = 1134.9 pm, α = 94.19° (1582 observed, independent reflexions, R = 0.023); [MoCl3(N3S2)(C4H8O)], a = 1069.7, b = 1002.5, c = 1122.0 pm, β = 93.77° (1440 reflexions, R = 0.024). In the molecules, the Mo atoms are members of nearly planar MoN3S2 rings with MoN bond distances between 178 and 185 pm , which correspond to double bonds. The sixfold coordination of the Mo atoms is completed by three chlorine atoms and the N or O atom of the pyridine or tetrahydrofuran ligand, respectively. The solvate molecules are in trans positions to one of the N atoms and form dihedral angles of 34.0° and 41.4° with the M oN3S2 rings, respectively.
Preparation and Crystal Structure of New 1,3-Diaza-λ5,λ5-diphosphetidines
Authors: Donath Ch. , Meisel M. , Jost K .-H . , Palkina K. K. , Maksimova S. I. , Čibiskova N. T.
Published: March 2015

Abstract Reaction of py · PS2Cl (py = pyridine) with benzyl amine in the presence of NEt3 yields triethyl-ammonium 1,3-dibenzyl-2,4-dithioxo-1,3-diaza-2λ5,4λ5-diphosphetidine-2,4-dithiolate which reacts with MeI to give the corresponding methyl ester. By fractional crystallization from cyclohexane three modifications of the methyl ester were obtained (two trans-(A and A') and one cis-modification (B)). The crystal structure of these modifications have been determined by single crystal X-ray diffraction. Crystal data: A: triclinic, space group P1̄ , Z = 2, a = 7.100(3), b = 10.088(6), c = 17.785(6) Å , α = 99.18(4)°, β = 93.75(5)°, γ = 106.96(4)°, A': monoclinic, P21/c, Z = 2, a = 7.933(3), b = 13.689(3), c = 9.917(4) Å, β = 111.98(3)°; B: orthorhombic, P cab, Z = 8, a = 12.962(6), b = 16.581(6), c = 19.475(7).
Ligandensubstitution an cis-Mo(CO)2(PPh3)2(MeCN)(η2-SO2), Kristall- und Molekülstruktur von cis-Mo(CO)2(PMe3)3(η2-SO2) / Ligand Substitution at cis-Mo(CO)2(PPh3)2(MeCN)(η2-SO2), Crystal and Molecular Structure of cis-Mo(CO)2(PMe3)3(η2-SO2)
Authors: Baumann Franz-Erich , Burschka Christian , Schenk Wolfdieter A .
Published: March 2015

Mo(CO)2(PPh3)2(MeCN)(η2-SO2), reacts with a number of unidentate or tridentate phosphines with displacement of both MeCN and PPh3. Mixtures of up to three different isomers are obtained the structures of which are assigned by IR , 1H, 13C, and 31PNMR , and in one case by X-ray crystallography. The results support earlier observations concerning the relationship between the disposition of donor and acceptor ligands around the metal and the bonding mode of SO2 .
The Crystal and Molecular Structure of Dichloro Monothiodibenzoylmethanato Indium Monothiodibenzoylmethane InCl2L(LH)
Authors: Mishra Anil K. , Gupta Vishnu D . , Nöth Heinrich
Published: March 2015

Indium trichloride reacts with 2 moles of monothiodibenzoylm ethane (LH) in the presence of sodium acetate to yield In Cl2L(LH). According to an X-ray structure analysis the molecule possesses a hexacoordinated indium atom with two chlorine atoms in cis position and two sulfur atoms in trans position. The symmetry of the molecule is C2 imposed by a crystallographic twofold axis. The unique hydrogen atom , assumed to form an intermolecular hydrogen bridge between oxygen atoms could not be detected in the structure analysis.
Photooxidation of Methylbenzenes and Methylnaphthalenes Sensitized by Cyanoanthracenes
Authors: Albim Angelo , Spreti Silvia
Published: March 2015

9-Cyanoanthraccne, 9,10-dicyanoanthracene and 3,7,9,10-tctracyanoanthraccne photosensitize the oxidation in acetonitrile of toluene, durene. hexamethylbenzene, 1-methyl- and 2-methvl- naphthalene to the corresponding aldehydes, with low yield of the alcohols and. in the case of hexamethylbenzene, of tetramethylphthalidc. In benzene, only hexamethylbenzene reacts through a different pathway involving singlet oxygen. Comparison with fluorescence quenching data and experiments in the presence of good donors, halides or radical traps, as w-ell as the effect of solvents and of oxygen concentration show that the reaction involves electron transfer from the methylaromatic to the singlet excited state of the sensitizer, followed by proton transfer to CA˙̄ or O2˙̄ yielding benzyl radicals, which react with oxygen or can be trapped.
Synthesis of Water Soluble Spin Labeled Glucose Derivatives as Potential NMR Contrast Enhancing Agents
Authors: Sosnovsky George , Rao N. Uma Maheswara , Lukszo Jan , Brasch Robert C.
Published: March 2015

Synthetic methodologies for the preparation of nitroxyl labeled derivatives of D -(+)-glucose, α -D -(+)-m ethylglycoside, 2-amino-2-deoxy-D -(+)-glucose, and D -(+)-glucuronic acid are presented. The spin labels in these compounds are attached variably at the 1, 2, 3, and 6 positions of the glucose framework. These new compounds, being water soluble and producing marked en­hancement of spin-lattice (T ,) and spin-spin (T2) proton relaxation in deionized water and human plasma have potential utility as contrast altering pharmaceuticals for magnetic resonance imaging and as spin probes in biomolecular research. These spin labeled carbohydrates may demonstrate in vivo biodistribution characteristics reflecting tissue-specific differences in glucose metabolism .
Synthesen mit Cyclobutadienen, 14 [1]. Tetra-tert-butylprismane durch Dewarbenzol-Isomerisierung / Syntheses with Cyclobutadienes, 14 [1]. Tetra-tert-butylprismanes by Dewarbenzene-Isomerization
Authors: Wingert Horst , Regitz Manfred
Published: March 2015

The kinetically stabilized cyclobutadiene 2 undergoes [4+2]-cycloaddition reaction at elevated temperature with the acetylenecarboxylate 3 to yield the regioisomeric dewarbenzenes 5 and 6. They are transformed into the prismanes 7 and 8 by a photochemical intramolecular [2+2]- cycloaddition process. Under thermal conditions (150 °C) this isomerization reaction is reversible (7→5, 8→6).
Synthese und Struktur von [Fe(SPh)2(NO)2]- dem „Monomeren“ des Roussinschen Phenylesters/ Synthesis and Structure of [Fe(SPh)2(NO)2]- , the “Monomer” of Roussin’s Phenyl Ester
Authors: Strasdeit Henry , Krebs Bernt , Henkel Gerald
Published: March 2015

The complex (Et4N )[Fe(SPh)2(NO)2] (2) has been obtained as black crystals by treatment of K[Fe4S3(NO)7]·H2O with potassium hydroxide in molten diphenyldisulfide and subsequent addition of methanol and tetraethylammonium chloride. 2 is orthorhombic, space group Pbca, Z = 8, with a = 18.853(3), b = 17.958(3), and c = 13.283(2) Å at 140 K. The X-ray structure of 2 has been refined to R1 (R2) = 2.7% (3.1% ). It reveals a pseudotetrahedral S2N2 arrangement around the iron atom (Fe -S 2.280, Fe -N 1.679 Å (mean values), S -Fe -S 109.73(2)°, N -Fe -N 117.36(9)°) and Fe -N -O groups of the linear type (N -O 1.180 Å , Fe -N - O 169.0° (mean values)). The N - O bond order is 2.2. Structural properties as well as the low Mößbauer isomeric shift ( + 0.08 mm/s relative to Fe metal) are indicative of strong Fe - N π-back bonding and a major contribution of the mesomeric form Fe = N = Ō̱

.
Benzoatokomplexe des Rutheniums, 2. Mitt. Synthese, Eigenschaften und Kristallstruktur von Ru2(C6H5COO)2(CO)4, Ru2(C6H5COO)2(CO)6 und Ru2(CH3COO)2(CO)6/Benzoato Complexes of Ruthenium, Part 2 Synthesis, Properties and Crystal Structure of Ru2(C6H5COO)2(CO)4, Ru2(C6H5COO)2(CO)6 and Ru2(CH3COO)2(CO)6
Authors: Spohn Martin , Vogt Thomas , Strähle Joachim
Published: March 2015

The reaction of Ru3(CO)12 with molten benzoic acid yields Ru2(C6H5COO)2(CO)4 (1) and Ru2(C6H5COO)2(CO)6 (2). Ru2(CH3COO)2(CO)6 (3) was obtained in small yield by annealing Ru2(CH3COO)2(CO)4 over a period of 3 weeks at 145 °C in a sealed glass am poule. 1 forms orthorhombic, orange needles crystallizing in the space group Pbca, with the lattice constants a = 974.9, b = 2090.5, c = 1830.1 pm, Z = 8 . 2 crystallizes as monoclinic, yellow needles in the space group C2/m with a = 1879.2, b = 1168.3, c = 1029.3 pm, β = 103.77°, Z = 4. 3 is obtained in the form of yellow platelets which crystallize in the space group P 21/c and with lattice constants a = 792.3, b = 2802.6, c = 1440.9 pm, β = 100.65°, Z = 8. All three complexes consist of dimeric units Ru2(RCOO)2(CO)4 with bridging carboxylato groups in cis positions. In the case of 1 these units are linked together by additional Ru -O bonds between neighbouring dimers to form polymer chains. 2 and 3 are isolated complexes with the axial positions occupied by CO ligands. The diamagnetism as well as the Ru -Ru distances (1: 263.9 pm; 2: 270.4 pm; 3: 269.0 and 268.8 pm) are in agreement with a Ru-Ru single bond and the electron configuration σ2π4δ2δ∗2. Polymer 1 reacts reversibly with CO at 1 bar pressure to form 2.
Darstellung von Chalkogenostibanen des Typs R2SbER′ (R = CH3, C2H5; E = S, Se, Te; R′ = CH3, C6H5) durch Austauschreaktionen zwischen Distibanen und Dichalkogeniden/ Preparation of Chalcogenostibanes of the Type R2SbER′ (R = CH3, C2H5; E = S, Se, Te; R′ = CH3, C6H5) by Exchange Reactions of Distibanes and Dichalcogenides
Authors: Breunig Hans Joachim , Gülec Sabahittin
Published: March 2015

Chalcogenostibanes of the type R2SbER′ (R = CH3, C2H5; E = S, Se, Te; R′ = C H3, C2H5) have been prepared by complete exchange reactions of the corresponding distibanes and dichalcogenides. The derivatives (CH3)2SbTeCH3 , and (C2H5)2SbTeCH3 are thermochromic.
Synthese und Struktur von Dicarbonyl(η5-pentaphenylcyclopentadienyl)rhodium, (η5-C5Ph5)Rh(CO)2
Authors: Behrens Ulrich , Edelmann Frank
Published: March 2015

(η5-C5Ph5)Rh(CO)2 has been prepared in 62% yield by treatment of [Rh(CO)2Cl]2 with NaC5Ph5 in THF. The title com pound crystallizes in the rhombic space group Pcab with the lattice parameters a = 2064.7(7) pm , b = 2065.2(8) pm, c = 1407.6(6) pm and Z = 8 . The crystal structure consists of discrete (η5-C5Ph5)Rh(CO)2 molecules and the Rh(CO)2 fragment adopts an eclipsed conformation relative to the cyclopentadienyl ring.
Spectral, Magnetic and Thermogravimetric Studies of Some Dimeric Oxovanadium(IV) Complexes
Authors: Nath P. K. , Mishra N. C. , Chakravortty V. , Dash K. C.
Published: March 2015

The tridentate dibasic Schiff base anthranilic acid salicylideneimine (H2SB) reacts with VOCl2 in the presence o f NaOAc and imidazole (or its derivatives) to form dimeric oxovanadium (IV) complexes of the type [VO(S B)(D)]2. These green or yellow -green compounds have a magnetic moment of 1.4 B.M . at room temperature, and are non-electrolytes in MeOH . The compounds are characterised on the basis of electronic and IR spectra as well as EPR spectroscopy. The IR spectra shows a strong band due to v(V = O) at 880 cm-1 in addition to the bands of H2SB and imidazole. [VO(SB)(Im)]2 shows a single unresolved EPR signal at g = 1.9715 whereas compounds containing other imidazole derivatives show both a broadening and shifting of the signal. The thermogravimetric measurements indicate the stability of the complexes and their stepwise thermal decomposition.
Metallkomplexe mit biologisch wichtigen Liganden, XLIII Metallkomplexe mit ungeschützten acyclischen Monosaccharid-Derivaten (Amin-, Oxim-, Schiffbase-, Thiazolidin-und 1,3-Dithian-Liganden)/Metal Complexes with Biologically Important Ligands, XLIII Metal Complexes with Unprotected Acyclic Derivatives of Monosaccharides (Amine, Oxime, Schiffbase, Thiazolidine and 1,3-Dithiane Ligands)
Authors: Nagel Yvonne , Beck Wolfgang
Published: March 2015

The synthesis and spectroscopic data of palladium (II), platinum (II), nickel(II), cobalt(II), copper(II) and gold(I) complexes with D-glucose oxime, 2-amino-2-deoxy-D-glucose oxime, 1,2-diamino-1,2-deoxy-D-glucitole, L-cysteine-D-glucose, D-glucose trimethylene mercaptale. Schiffbases from 1,2-diamino-1,2-deoxy-D -glucitole and acetylacetone or from D-glucosone and 1.3-diaminopropane are reported.
Erdalkaliquadratate, II SrC4O4 · 3H2O Typ I [1] / Alkaline-Earth Squarates, II SrC4O4 · 3H2O Type I [1]
Authors: Robl Christian , Weiss Armin
Published: March 2015

In SrC4O4-3H2O (type I), Sr2+ has CN 8. It is surrounded by 3 water molecules and 5 oxygen atoms of 4 different squarate dianions. The C-O and C-C bond lengths are typical of extensive delocalization of the π-electron system. The connection of Sr2+ and C4O4
2- leads to infinite layers, obviously interlinked by hydrogen bonding.

The oxygens of the squarate behave differently: two are Sr-chelating, but simultaneously bound to two additional Sr2+, one is connected with one Sr2+ only, and the fourth is not bound to any Sr2+. The single crystal character remained in principle unchanged during dehydration to SrC4O4 · 1 H2O and subsequent rehydration to the trihydrate. Grinding of a crystal treated in this way led to a new modification of SrC4O4 ·3 H2O.
Ein neues quaternäres Oxocadmat: Cs2K2Cd3O5 [1] / A New Quaternary Oxocadmate: Cs2K2Cd3O5 [1]
Authors: Seipp Erhard , Hoppe Rudolf
Published: March 2015

Cs2K2Cd3O5 has been prepared from mixtures of the binary oxides in a silver-tube (550 °C. 17 days). The unit cell is triclinic, P1̄ (a = 983.2, b = 918.0, c = 653.5 pm. α = 108.3°, β = 113.7°, γ = 99.9°. The crystal structure was refined to R = 5.9% and /?u = 5.8% (four-circle-diffractome­ter data, 2616 unique of 3359 measured reflexions). The Effective Coordination Numbers (ECoN) and the Madelung Part of Lattice Energy (MAPLE) are calculated and discussed.
Synthese und Kristallstruktur von Mg[Si(CH3)3]2 · (CH3)2NCH2CH2CH2N(CH3)2 / Synthesis and Crystal Structure of Mg[Si(CH3)3]2 · (CH3)2NCH2CH2CH2N(CH3)2
Authors: Rösch Lutz , Pickardt Joachim , Imme Sigrid , Börner Ute
Published: March 2015

Mg(SiMe3)2 · TMDAP was synthesized by reaction of Hg(SiMe3)2 with magnesium in 1,3-bis-(dimethylamino)propane/diethyl ether. The crystal structure of the compound was investigated.
Polyphosphinhaltige Trichlorostannatoplatin(II)-Komplexe: Synthese und NMR(119Sn, 31P)-Charakterisierung / Trichlorostannatoplatinum(II) Complexes Containing Polyphosphines: Synthesis and NMR (119Sn, 31P) Characterization
Authors: Brüggeller Peter
Published: March 2015

Trichlorostannatoplatinum(II) complexes containing bis(2-diphenylphosphinoethyl)phenyl- phosphine, etp, and the tripod ligand tris(2-diphenylphosphinoethyl)phosphine, PP3, respective­ly, have been prepared and characterized by 119Sn{1H} and 31P{1H} NMR spectroscopy. [(etp)PtCl](BPh4) (1a) reacts with SnCl2 via oxidative addition to give [(etp)PtSnCl3](BPh4) (1b). The 31P NMR spectral patterns of type 1 complexes are consistent with AX2 spin-systems and square planar structures in solution. There is 31P NMR evidence that in the presence of (Ph4P)Cl 1b adds further SnCl2. The possibility of the formation of [(etp)Pt(SnCl3)2] (2) is discussed. [(PP3)PtCl](BPh4) (3a) reacts with SnCl2 to give [(PP3)PtSnCl3](BPh4) (3b). The 31P NMR spec­tral patterns of 3a and 3b are consistent with AX3 spin-systems and trigonal bipyramidal struc­tures.
Reductive Dehalogenation of α-Haloketones by Sodium Borohydride and Tin(II) Chloride in Tetrahydrofuran
Authors: Ono Aoi , Yamaguchi Ritsuko , Shirai Yoshiko
Published: March 2015

α-H aloketones and α-halocarbonyl compounds are effectively reduced to dehalogenation to their corresponding parent ketones or carbonyl compounds in good yield by sodium borohydride and tin(II) chloride in tetrahydrofuran.
Some New Derivatives of Harmaline Series of Bases
Authors: Siddiqui Salimuzzaman , Siddiqui Bina S. , Begum Sabira
Published: March 2015

In the course of pharmaco-chemical studies in the structure and activity relationship in harmaline series of β-carboline bases, a number of new derivatives of harmaline have been obtained and characterized through chemical and spectral studies. Pharmacological screening carried out on one of these (9) shows that it has mild physiological activity without any toxicity.
Einkristallzüchtung und Röntgenstrukturanalyse polymerer 1:1-Komplexe von CuBr2 und CuCl2 mit Pyrazin aus Gelen / Crystal Growth in Gels and X-Ray Characterization of Polymeric 1:1-Complexes of CuBr2 and CuCl2 with Pyrazine
Authors: Fetzer Th. , Lentz A. , Debaerdemaeker T.
Published: March 2015

Single crystals of Cu(pz)Br2 and Cu(pz)Cl2 were grown by using gel methods with tetramethoxysilane as the gel-forming reagent. Thermal decomposition is interpreted. Crystal data for the bromo complex: monoclinic, space group C2/m with a = 1239.2(3) pm, b = 685.9(2) pm, c = 390.7(3) pm, β = 96,23(5)°. Crystal data for the chloro-complex: monoclinic, space group C2/m with a = 1197.1(3) pm, b = 684.9(3) pm, c = 370.1(3) pm, β = 95.96(5)°. Crystal structure analyses reveal that CuHal2 molecules are bonded by pyrazine to form linear chains. These chains are cross-linked by bridging halogen atoms.
Degradation of Lactic Acid and Pyruvic Acid in Belousov-Zhabotinskii Reactions
Authors: Blume Rüdiger , Wiechoczek Dagmar , Meier Heinrich , Wedekind Frank
Published: March 2015

The temporal degradation of the Belousov-Zhabotinskii substrates lactic acid, pyruvic acid, bromo- and dibromo pyruvic acid is investigated. The only final product of non-brominated substrates is acetic acid. From brominated educts only brominated acetic acids result. The concentrations of the stable products are determined as a function of time. The gross reactions are mainly based on simple consecutive first order reactions. For the pyruvic acid rate constants are determined.
The structures of indoiyl(alkoxy)carbenium tetrafluoroborates: a new class of highly stabilized carbenium ions
Authors: Pindur Ulf , Pfeuffer Ludwig , Flo Camran , Massa Werner , Seitz Karin
Published: March 2015

The conformations of and charge distributions in indolyl(alkoxy)carbenium tetrafluoroborates 2, a new class of highly stabilized carbenium ions, were investigated by 1H and 13C NMR spectroscopy and the crystal structure of indol-3-yl(methoxy)phenylcarbenium tetrafluoroborate (2e) was determined by X-ray diffraction methods. The phenyl-substituted cation of 2e exhibits axial chirality in the crystalline state
Isonitril-substituierte Halbsandwich-Komplexe von Wolfram(IV) / Isonitrile Substituted Half Sandwich Complexes of Wolfram(IV)
Authors: Filippou Alexander Constantin , Grünleitner Walter
Published: March 2015

A good entry to cyclopentadienyl substituted isonitrile complexes of W(IV) is provided by CpW(CO)(t-BuNC)(I)3 (4), prepared by oxidative decarbonylation of cis- or trans-CpW(CO)2(t-BuNC)I (2,3) with elemental iodine. The isomers 2 and 3, separable by column chromatography on silica at low temperature, are easily obtained from CpW(CO)3I (1) and t-BuNC using Me3NO as a decarbonylating agent. Compound 4 reacts with t-BuNC to yield a mixture of the cationic complexes [CpW(CO)(t-BuNC)2(I)2]I (5) and [CpW(t-BuNC)3(I)2]I (6). The neutral cyano complex CpW(CN)(t-BuNC)2(I)2 (7), resulting from the dealkylation of one tert-butylisonitrile ligand, is also obtained. The insoluble main product 5 is easily separated from 6 and 7, and is converted with AgBF4 to the corresponding BF4-salt [CpW(CO)(t-BuNC)2(I)2]BF4 (8). The soluble byproducts 6 and 7 have been purified by column chromatography on silica. The composition and structure of the new complexes 4-8 have been derived from elemental analyses and spectroscopic investigations. The ionic nature of 6 and 8 has been confirmed by comparison of their conductivity data in 1,2 dichloroethane with that of NR4
+X- salts (R = alkyl; X = Br, I)
Empirical Parameters of Lewis Basicity of Binary Solvent Mixtures, Part II Mixtures with Water
Authors: Wrona Piotr K. , Krygowski Tadeusz M. , Zielkowska Urszula
Published: March 2015

The Kamlet and Taft basicity parameters βKT, for twelve mixtures of organic solvents with water are reported. Also the data for water-butanols (n-BuOH. i-BuOH. and s-BuOH) and alcohols (MeOH, EtOH. n-PrOH. and i-PrOH)-n-hexane mixtures are given. It was found that in the case of mixtures of 1.4-dioxane. acetone, tetrahydrofuran. dimethylsulfoxide. and acetonitrile with water, the basicity parameters of the mixture are higher than that of pure solvents in a region of smaller concentrations of water.

These results, together with earlier reported results for THF and Et2O mixtures with MeOH are discussed in terms of breaking off the structure of the more structurized solvent (water and MeOH). All these mixtures, except the W-THF mixture, show the excess thermodynamic func­tions (ΔHE and ΔSh) analogous to MeOH-CCl4 mixtures, where depolymerization of MeOH clusters was postulated.

Relativity of different basicity scales in respect to the acidic probe molecule is also shortly discussed
Studies on Alkyl Heterocyclic Aromatic Compounds: New Routes for the Synthesis of Polyazanaphthalenes
Authors: Elnagdi Mohamed Hilmy , Abdel Aal Fatma Abdel Maksoud , Hafez Ebtisam Abdel Aziz , Yassin Youssef Mahfouz
Published: March 2015

Several new polyfunctionally substituted polyazanaphthalene derivatives could be synthesized via condensing readily obtainable polyfunctional nitriles with substituted alkyl heteroaromatic derivatives and reacting the latter derivatives with electrophilic reagents
Oberflächen-Reaktionen, 9 Dehydrohalogenierungen von Halogenkohlenwasserstoffen an Raney-Nickel / Surface Reactions, 9 Dehydrohalogenation of Halohydrocarbons at Raney Nickel
Authors: Bock Hans , Wolf Hans Peter
Published: March 2015

Raney nickel, a highly reactive and air-sensitive solid, if prepared and investigated under oxygen-free conditions, exhibits interesting catalytic properties. Using photoelectron spectroscopy for real-time gas analysis in a flow reactor, the following results are obtained with alkyl and acylhalides: Dehydrohalogenation temperatures are lowered relative to thermal HHal elimination up to 350 K. Monochloro and bromo propanes and butenes yield propene and butadiene, respectively. 1,1-Dichloro ethane or 1,1-dibromo propane only split off one HHal and form chloroethene or 1-bromopropene-2. HCl elimination from 2-methyl propionic acid chloride, expectedly, produces dimethyl ketene. Most interesting, however, is the ring opening of monobromo cyclobutane to 1-bromo-butene-3, observed already at room temperature, which strongly suggests the intermediate formation of a chemisorbed surface carbene at Raney nickel. The formation of hexadiene-1,5 as a by-product in the HCl elimination of 1-chloropropane, i. e. a surface carbene dimer, indicates their presence also in other dehydrohalogenations heterogeneously catalyzed by Raney nickel.
Structural and Transport Studies for Ternary Graphite Intercalated Phases (CoCl2, AlCl3)
Authors: Pernot Paul , Vangelisti René
Published: March 2015

Metal dihalide low-volatility is the major characteristic slowing down their intercalation into graphite (GICs: graphite intercalation compounds). An original synthesis using volatile heterocomplexes between metal dihalide (CoCl2) and gaseous dimer Al2Cl6 increases strickingly CoCl2 intercalation rate but entails cointercalation of significative amount of AlCl3 in the compounds MGICs (mixture graphite intercalation compounds). Structural studies along c-axis, in plane and out the plane (3 D stacking) display a similar behaviour as in the CoCl2 containing binary compounds. Microstructural studies confirm the separation of CoCl2 and AlCl3 in distinct domains. Other ternary phases with alternate CoCl2 and AlCl3 layers and characterized by a similar AlCl3/CoCl2 ratio can be obtained using biintercalation method: (GBICs: graphite biintercalation compounds).

X-Ray diffraction shows that the biintercalation involves a complete lost of correlations in the successive CoCl2 or graphite layers. Transport studies of ternary phases (MGICs and GBICs) display an anomalous behaviour as T is lowered below the magnetic ordering temperature Tc especially for in plane resistivity.
Polarographische Untersuchungen zur Bestimmung der Stabilität von Metall-Protein-Bindungen / Polarographic Investigations for the Determination of the Stability of Metal-Protein Bonds
Authors: Reinecke H. , Dunemann L. , Schwedt G.
Published: March 2015

Bonds between metals (especially copper) and a protein fraction (18,100 g/mol) of a soya bean flour extract have been investigated. The binding capacity (304 nmol Cu/mg protein) and the binding stability (K = 1,046·103 in an ammonia buffer system) were determined by polarographic investigations. Changes in the polarogram caused by spiking the protein with metal ions were compared with effects in model substances. Cysteine, ethylenediamine, oxalic acid and derivatives of benzoic acid were used as chelating agents. The effects of functional groups on the metalprotein bonds were estimated by the determination of their different binding stabilities.
Synthesis of Bicyclic and Tricyclic Enones via Regioselective Dialkylation of Cyclic 1,3-Diketone-dimethylhydrazones with 4-Chlorobutane-2-one
Authors: Demir Ayhan S. , Enders Dieter
Published: March 2015

An efficient, regioselective synthesis of substituted bicyclo nonenes and decenes of type (4a, b) and the tricyclic tetradecadiene (5) is described. The key step is the regioselective dialkylation of cyclic 1,3-diketone-dimethylhydrazones (la—e) with 4-chlorobutane-2-one.
1-Acceptorsubstituierte Vinamidiniumsalze: Stabilität und Reaktivität / 1-Acceptor Substituted Vinamidinium Salts: Stability and Reactivity
Authors: Bacher Erwin , Gompper Rudolf , Mertz Ronald , Wagner Hans-Ulrich
Published: March 2015

1-Chloro- and 1,3-dichloro-vinamidinium salts react with potassium cyanide to afford 1-cyanoand 1,3-dicyano-vinamidinium salts. The former add nucleophiles at the C-3 position. MNDO calculations, competitive hydrolysis experiments and cyclic voltammetry reveal the following sequence of stabilities of vinamidinium salts: 1,3-(NMe2)2 > 1-NMe2 > 2-Aza > H > 2-(p-MeOC6H4) > 2-OMe > 2-Cl > 2-CN > 1,3-(SMe)2 > 1-Cl > 1-CO2Et > 2-NO2 > 1-CN > 1,3-(CN)2. Interestingly enough, reduction potentials show that a 1,3-dicyanovinamidinium salt is more stable than a 1,3-dichlorovinamidinium salt, whereas a 1-chlorovinamidinium salt is more stable than a 1-cyanovinamidinium salt.
Valence Force Constants of N-Benzylideneanilines
Authors: Figueroa K. , Peña R. , Campos-Vallette M. M.
Published: March 2015

Valence force constants for N-benzylideneaniline and for two p,p′-disubstituted derivatives were estimated by means of a point-charge model using CNDO data. A vibrational assignment of bands which are sensitive to the electron donor-acceptor characteristic of substituents is proposed. The conformational changes are interpreted in terms of an intramolecular energy transfer between substituents.
Synthese und Strukturuntersuchungen von Iodocupraten(I) X. [Co(cp)2]2[CuI3] und [Co(cp)2][Cu2I3] = 1/9{[Co(C(cp)2]9[Cu6I11]∞
2[(Cu6I8)2]} [1] / Syntheses and Structure Analyses of Iodocuprates(I) X. [Co(cp)2]2[CuI3] and [Co(cp)2][Cu2I3] = 1/9{[Co(cp)2]9[Cu6I11]∞
2[(Cu6I8)2]} [1]
Authors: Hartl Hans , Brüdgam Irene
Published: March 2015

Bis-(cobalticenium)triiodocuprate(I), [Co(cp)2]2[CuI3]≡(1) and cobalticenium-triiododicuprate(I), [Co(cp)2][Cu2I3]=1/9{[Co(cp)2]9[Cu6I11] ∞
2[(Cu6I8)2]}=(2) were obtained by reacting [Co(cp)2]I with CuI in acetone 1 and acetonitrile 2, respectively. The crystal structure of 1 exists of cobalticenium cations and mononuclear planar anions CuI3
2-. The crystal structure of 2 contains cobalticenium cations and two different types of iodocuprate(I) anions: an isolated hexa-nuclear ion Cu6I11
5- built up by 6 edge sharing CuI4 tetrahedra and polymeric layers ∞
2 [Cu6I8]2-. In the latter anion Cu6I11 components are two-dimensionally connected via 3 common edges and Cu(I) ions are distributed over two kinds of tetrahedral sites.
Synthese, Struktur und thermisches Verhalten von Thiophosphorsäuretriamid SP(NH2)3 [1] / Synthesis, Structure, and Thermal Behaviour of Phosphorothionic Triamide SP(ΝΗ2)3 [1]
Authors: Schnick Wolfgang
Published: March 2015

Phosphorothionic triamide SP(NH2)3 is obtained by slow addition of SPCl3 dissolved in dry CH2Cl2 to a satured solution of NH3 in CH2Cl2 at —50°C. Ammonium chloride is removed from the resulting precipitate by treatment with HNEt2 followed by extraction with CH2Cl2. Coarse crystalline SP(NH2)3 is obtained after recrystallization from dry methanol. The crystal structure of SP(NH2)3 has been determined by single crystal X-ray methods (Pbca; a = 922.3(1), b = 953.8(1), c = 1058.4(2) pm, Z = 8). In the crystals the molecules show non-crystallographic point symmetry C8. The P—S bond (195.4(1) pm) is slightly longer than in SPCl3. From P—N bond lengths of about 166 pm a significant electrostatic strengthening of the P—N single bonds is assumed. Weak intermolecular hydrogen bonding interactions (N —H · · · N ≥ 329.5 pm; N — H · · · S ≥ 348.3 pm) are observed.

Investigation of thermal properties shows a melting temperature of 115°C for SP(NH2)3. According to combined DTA/TG and MS investigations above this temperature the compound decomposes by evolution of H2S and NH3 to yield amorphous phosphorus(V)nitride.
Effect of Urea and Organic Solvents on the Mitochondrial F1 ATPase
Authors: Dreyfus George , Meis Leopoldo de
Published: March 2015

Mitochondrial F1 ATPase is inactivated by urea. Protection against urea inactivation is obtained when betaine, a methylamine found in different tissues, is added to the assay medium. Protection is also obtained upon the addition of either glycerol or dimethyl sulfoxide to the assay medium. The F, ATPase is rapidly inactivated at 4 °C. Inactivation by low temperature is prevented by betaine, glycerol and dimethyl sulfoxide. The protective effect of organic solvents and betaine against cold inactivation is prevented by urea.
Notizen: Refinement of the Crystal Structures of CuTe2Br and CuTe2I
Authors: Milius Wolfgang
Published: March 2015

The crystal structures of CuTe2Br and CuTe2I have been refined on the basis of single crystal data. Both compounds crystallize monoclinically in space group P21/c. The structures are isotypic with that of CuTe2Cl. The lattice parameters of CuTe2Br are a = 834.5(8) pm, b = 492.8(4) pm, c = 1573.3(5) pm and β = 135.3(2)°. The unit cell dimensions of CuTe2I are a = 866.5(8) pm, b = 491.4(4) pm, c = 1649.6(3) pm and β = 135.1(2)°.
Notizen: Austausch von Nitrit- gegen Bromidanionen in Na3NO3 / Replacement of Nitrite by Bromide Anions in Na3NO3
Authors: Jansen M. , Müller W.
Published: March 2015

Na3O(NO2) and Na3OBr are isostructural and form solid solutions with a miscibility gap χ = 0.28 to 0.62 as referred to Na3OBrx(NO2)1-x, at room temperature. Above 593 Κ formation of mixed crystals was observed for all compositions. In contrast to pure Na3O(NO2), the solid solutions do not undergo any phase transition in the investigated temperature range from 293 Κ to 130 K. These findings reveal that collective interactions between the dynamically disordered NO2
--groups are involved in the phase transitions of Na3NO3.
Synthese und Kristallstruktur von Europium(III)-diacetatotriaquo-chlorid, [Eu(CH3COO)2(H2O)3]Cl / Synthesis and Crystal Structure of Europium(III)-diacetatotriaquo-chloride, [Eu(CH3COO)2(H2O)3]Cl
Authors: Schleid Thomas , Meyer Gerd
Published: March 2015

Colourless single crystals of [Eu(CH3COO)2(H2O)3]Cl are obtained at about 5°C from a solution of EuCl3 · 6 H2O in a mixture of acetone, tetrahydrofurane and acetanhydride (1:1:2) to which a small amount of water had been added. [Eu(CH3COO)2(H2O)3]Cl crystallizes in the monoclinic system, space group P21/n (No. 14), a = 786.19(5), b = 791.86(5), c = 1768.81(13) pm; β = 98.235(6)°, R = 0.025, Rw = 0.021, Z = 4. Eu3+ is in nine-coordinate surrounding of O2-, three of which belong to water molecules and six to acetate anions (two bidentate and two monodentate). Cationic chains of the composition [Eu(CH3COO)2(H2O)3]+ are formed through further connection via acetate-oxygen atoms. These chains are stacked hexagonally parallel [100] and held together by “lonesome” Cl- anions. The chloride ions are surrounded by 4+1 aquo ligands.
Tetraphenylphosphonium-hexachlorodizinkat und -hexachlorodicadmat, (PPh4)2Zn2Cl6 und (PPh4)2Cd2Cl6 / Tetraphenylphosphonium Hexachlorodizincate and Hexachlorodicadmate, (PPh4)2Zn2Cl6 and (PPh4)2Cd2Cl6
Authors: Wilhelm Jörg Hubertus , Müller Ulrich
Published: March 2015

The title compounds were obtained by the reactions of PPh4Cl, HCl and ZnS or CdS in CH2Cl2. Their crystal structures were determined by X-ray diffraction. (PPh4)2Zn2Cl6: a = 973.6(1). b = 982.6(2), c = 1296.7(3) pm, α = 107.93(2), β = 94.50(2), γ = 100.91(2)°, R = 0.036 for 2237 unique observed reflexions. (PPh4)2Cd2Cl6: a = 977.1(2), b = 997.5(3). c = 1306.6(3) pm. α = 108.81(2), β = 94.18(2), γ = 100.24(2)°, R = 0.050 for 1921 reflexions. Both compounds are isotypic in the triclinic space group P1̄ and consist of PPh4
+ ions and dimeric, centrosymmetric M2Cl6
- ions in which the tetrahedrally coordinated metal atoms are linked via chloro bridges.
Li2ZnI4, das erste Iodid mit Olivinstruktur / Li2ZnI4, the First Olivine Type Iodide
Authors: Lutz Heinz Dieter , Pfitzner Arno
Published: March 2015

In the system LiI — ZnI2, the hitherto unknown peritectically melting Li2ZnI4 has been established. It crystallizes in the olivine structure (a = 1480.3(9), b = 856.0(2), and c = 701.2(1) pm) and exhibits high ionic conductivity. Thermoanalytical and Raman spectroscopic data are included.
Photochemische Studien, 55 [1]. Photodimerisierung von Nootkaton in kristallinem Zustand / Photochemical Studies, 55 [1]. Photodimerization of Nootkatone in Crystalline State
Authors: Reisch Johannes , Ekiz-Gücer Nurten , Takács Mihály
Published: March 2015

On UV irradiation, nootkatone (1) dimerizes in the crystalline state to give 2, 3 and 4. The dimerized products are formed through cycloadditions and radical reactions.
Zuordnung der 1H-NMR-Spektren von Depsiden, Depsidonen, Depsonen und Dibenzofuranen aus Flechten durch NOE-Differenzspektroskopie / Assignment of 1H NMR Spectra of Depsides, Depsidones, Depsones and Dibenzofurans from Lichens by NOE Difference Spectroscopy
Authors: Jakupovic Jasmin , Huneck Siegfried
Published: March 2015

The 1H NMR spectra of the following lichen substances have been correlated by NOE difference spectroscopy: atranorin, barbatic acid, diffractaic acid, nephroarctin, perlatolic acid, planaic acid methyl ester, pseudocyphellarin A, sphaerophorin (depsides), hypoprotocetraric acid, lobaric acid, pannarin, physodalic acid, psoromic acid, stictic acid (depsidones), picrolichenic acid (depsone), di-O-methyl-pannaric acid dimethylester, pannaric acid, porphyrilic acid, schizopeltic acid, strepsilin, and usnic acid (dibenzofurans).
Synthese und ferroelektrische Eigenschaften chiraler Ester von 2,5-Diphenylpyrimidinen mit α-Fluorcarbonsäuren / Synthesis and Ferroelectric Properties of 2,5-Diphenylpyrimidines with Different α-Fluorocarboxylic Acids
Authors: Bömelburg Jan , Heppke Gerd , Ranft Andreas
Published: March 2015

Chiral esters of 2-[4-n-hexylphenyl]-5-[4-hydroxyphenyl]pyrimidine and 2-[4-n-hexyloxyphenyl]-5-[4-hydroxyphenyl]pyrimidine with four different α-fluorocarboxylic acids have been synthesized. The spontaneous polarization and the tilt angles in the smectic C* phase were measured as a function of temperature. All compounds exhibit wide range smectic C* phases, the highest values of the spontaneous polarization being about 400 nC/cm2. Additionally the spontaneous polarization in a higher ordered smectic phase was determined, the values ranging up to about 600 nC/cm2. The spontaneous polarization/tilt angle ratio strongly increases with decreasing temperature.
Untersuchungen zur Chemie von Isoindolen und Isoindoleninen, XXXV [1]. 1-Alkoxy-2-alkyl-2 H-isoindole — o-chinoide Hetarene mit unsymmetrischer Struktur / Studies on the Chemistry of Isoindoles and Isoindolenines, XXXV [1]. 1-Alkoxy-2-alkyl-2H-isoindoles — o-Quinonoid Hetarenes with Unsymmetric Structure
Authors: Kreher Richard P. , Hennige Hans , Jelitto Frank , Preut Johannes
Published: March 2015

3-Alkoxy-2-methyl-1 H-isoindolium salts have been prepared either via regioselective O-alkylation of the corresponding 2-alkyl-isoindoline-1-ones or via regioselective N-alkylation of 3-alkoxy-1 H-isoindoles with trialkyloxonium tetrafluoroborates or with alkyl trifluoromethanesulfonates. Deprotonation of these stable precursors leads to the generation of reactive 1-alkoxy-2-alkyl-2H-isoindoles in solution. Reactions with CC-dienophiles (N-substituted maleic imides) give rise to the formation of 1 : 2-adducts. The two step reaction comprises Michael-addition and Diels-Alderaddition; the isolation of an initially formed 1:1-adduct is possible in the case of steric hindrance. Constitution and configuration of a representative 1 : 2-adduct has been established by X-ray crystal structure determination.
Notizen: Triorganoantimonverbindungen als Liganden in Eisenkomplexen / Triorganoantimony Compounds as Ligands in Iron Complexes
Authors: Wieber M. , Höhl H.
Published: March 2015

UV irradiation of trans-(CO)3Fe[P(OPh)3]2 yields an intermediate with loss of CO. This reacts with triorganostibanes SbR3 to give products (CO)2Fe[(PhO)3P]2(SbR3) with R = phenyl, 4-methylphenyl and cyclohexyl.
Über die Reduktion von Alkinkomplexen des Molybdäns und Wolframs in hohen Oxidationsstufen. Die Kristallstruktur von MoCl3(THF)3 / On the Reduction of Alkyne Complexes of Molybdenum and Tungsten in High Oxidation States. The Crystal Structure of MoCl3(THF)3
Authors: Hofacker Peter , Friebel Claus , Dehnicke Kurt , Bäuml Petra , Hiller Wolfgang , Strähle Joachim
Published: March 2015

The reduction of the tungsten alkyne complexes [WCl4(RC≡CR)]2 (R = Ph, SiMe3) with cobaltocen in THF solutions leads to the complexes [CoCp2]2[WCl4(RC≡CR)]2 (R = Ph (1); R = SiMe3 (2)), as green, oxygen sensitive crystalline powders. Reduction of [WCl4(Me3SiC=CSiMe3)]2 and of [MoCl4(PhC=CPh)]2 with sodium naphthalide in THF solutions in the presence of 15-crown-5 gives [Na-15-crown-5]3[W2Cl9], and MoCl3(THF)3, respectively. All compounds have been characterized by IR spectroscopy, and 1 and 2, in addition, by their EPR spectra. The crystal structure of MoCl3(THF)3 was determined by X-ray methods. Space group P21/c, Z = 4, 2642 observed unique reflexions, R = 0.050. Lattice dimensions at 20 °C: a = 888.4(2), b = 1281.5(3), c = 1535.2(3) pm, β = 92.17(2)°. The compound forms monomeric octahedral molecules with a meridional arrangement of the ligands.
Beiträge zur Chemie des Phosphors, 201 [1]. Pentaethyl-cyclopentaphosphan-monosulfid, (PEt)5S — Darstellung und 31P-NMR-spektroskopische Strukturbestimmung / Contributions to the Chemistry of Phosphorus, 201 [1]. Pentaethylcyclopentaphosphane Monosulfide, (PEt)5S — Preparation and Structure Determination by 31P NMR Spectroscopy
Authors: Baudler Marianne , Koch Peter
Published: March 2015

The first pentaorganylcyclopentaphosphane monosulfide (PEt)5S (1) has been obtained by the reaction of (PEt)5 with sulfur under proper conditions, and has been isolated in pure form. According to spectroscopic investigations sulfur is bound exocyclically to the five-membered phosphorus ring. Of the three possible configurational isomers only lb is formed due to steric reasons.