bluuebunny/crossref_metadata_2025 huggingface dataset:
An Unusual Electron Count and Electron-Deficient Multi-Center Bonding in One Class of Intermetallics: The BaAl4, CaAl2Zn2, CeMg2Si2 and FCC Al Structures
Authors: Zheng Chong , Hoffmann Roald
Published: March 2015

The structural types discussed may be thought of as being composed of two-dimensional layers cleaved out of the FCC lattice. Each layer has a square sublattice capped by apical atoms above and below four-fold hollows. The electronic structure of such an Al layer is constructed - it has eight low-lying bands per tour AI. and two of these bands are localized in apical Al s. pointing away from the layer. On stacking, bonds are formed between apical Al′s. leading to the pushing up of one Αla-ΑΙa σ* band, and a gap after 7 bands are filled. This is BaAl4, with Al4
2- . An alternative picture is of delocalized five-center six-electron bonding in each hollow, closely related to the electron deficient bonding in B5H9. The bonding in CeAl2Ga2 and CeMg2Si2 can be derived similarly, by perturbing the original BaAl4 case. A rationale for switching from BaAl, to the CeMg2Si2 structural type for electron counts exceeding ∼ 16 for four atoms is given. Finally we relate these arguments to the high cohesive energy of Al metal.
Synthese und Kristallstruktur von (PhSb)6 · 1,4-Dioxan, (PhSb)6 · Benzol und (PhSb)6 · Toluol. Oxidation von Silylstibanen zu Siloxistibanen / Synthesis and Crystal Structure of (PhSb)6 · 1,4-Dioxane, (PhSb)6 ·Benzene and (PhSb)6 ·Toluene. Oxidation of Silylstibanes to Siloxistibanes
Authors: Breunig Hans Joachim , Soltani-Neshan Ali , Häberle Karl , Dräger Martin
Published: March 2015

Slow air oxidation of PhSb(SiMe3)2 in 1,4-dioxane. benzene, or toluene gives (Me3Si)2O and crystals of (PhSb)6 · 1,4-dioxane, (PhSb)6 · benzene, or (PhSb)6· toluene, respectively. The crystal structure of the three isomorphous phases are reported. There are centrosymmetric Sb6 chairs with equatorial phenyl groups (total symmetry of the molecules approximately D3d, distances Sb-Sb 284 and Sb-C 216 pm. angles Sb-Sb -Sb 90°). The ring compounds are stabilized in forming stacks of (PhSb)ft molecules with short intermolecular Sb···Sb interactions (420 pm). The solvent molecules are needed for an optimum packing of these stacks. Air oxidation of PhSb(SiMe3)2 in the gas phase gives PhSb(OSiMe3)2. (Me3SiO)3Sb and Ph2SbOSiMe3 are formed, when Ph2SbSiMe3 is exposed to the air in an open flask. (Me3SiO)3Sb is also obtained from (Me3Si)3Sb and O2. Access of air to Ph2SbSiMe3 leads to 65% of Ph2SbOSiMe3.
Crosslinking of Gelatin with Formaldehyde; a 13C NMR Study
Authors: Albert Klaus , Peters Bernadette , Bayer Ernst , Treiber Ulrich , Zwilling Michael
Published: March 2015

The different species formed when gaseous formaldehyde is dissolved in aqueous medium are investigated by a 13C NMR flow-through technique and the spectra of commercial aqueous form­aldehyde solutions containing methanol completely interpreted.

13CH2O was used to study the crosslinking reaction with gelatin which leads to methylene and oxymethylene bridges between gelatin-amino-groups. On ageing, hardened gelatin shows an increase in the number of methylene bridges.
The Reaction of Arylidenemalonodinitriles with 1-Arylethylideneaminobenzenes. A New Synthesis of 5′-Amino-1,1′:3′, 1″-terphenyl-2′, 6′-dicarbonitriles
Authors: Milart Piotr , Sepioł Janusz
Published: March 2015

The reaction of arylidenemalonodinitrilcs with a variety of acetophenone anils leading to 5′-amino-1,1′:3′,1″-terphenyl-2′,6′-dicarbonitriles has been investigated. The mechanism of the exchange reaction between arylidenemalonodinitrilcs and 1-arylethylideneaminobenzenes is proposed.
Beiträge Zur Chemie Des Phosphors, 164 [1](t-Bup)2P -P (ME)-P (tBUP)2 - Das Erste Bis(Cyclotriphosphano)Phosphan, Ein Neuer P7R5-Strukturtyp / Contributions To The Chemistry Of Phosphorus, 164 (t-Bup)2P -P(ME)-P(R-BUP)2 - The First Bis(Cyclotriphosphano)Phosphane, A Novel P7R5 Structure Type
Authors: Bäudler Marianne , de Riese-Meyer Loert
Published: March 2015

The first bis(cyclotriphosphano)phosphane (t-BuP)2P -P(Me)-P (t-BuP)2 (1) has been synthesized by reacting (t-BuP)2PSnMe3 with MePCl2 in the molar ratio 2:1. With equimolar amounts of the reactants the chlorom ethylphosphino cyclotriphosphane (t-BuP)2P -P(Me)Cl (2) has been obtained. 1 represents a novel P7R5 structure type in addition to the types already known [4, 5]. The NMR parameters of 1 and 2 are reported and discussed
Die Reaktionen von Trithiazylchlorid mit Molybdän, Molybdäntrioxid und Natriummolybdat. Die Kristallstruktur von PPh4[MoCl4(N3S2)] und ihre Packung / The Reactions of Trithiazyl Chloride with Molybdenum, Molybdenum Trioxide and Sodium Molybdate. The Crystal Structure of PPh4[MoCl4(N3S2)] and its Packing
Authors: Wadle Heribert , Conradi Elke , Müller Ulrich , Dehnicke Kurt
Published: March 2015

Trithiazylchloride, (NSCl)3, reacts with Mᴏ, MᴏO3 or Na2MᴏO4 at 75 - 80 °C to give high yields of S4N3[MᴏCl4(N3S2)]. By interaction with a solution of PPh4Cl in CH2C12 this product can be converted into PPh4[MoCl4(N3S2)], from which [MᴏCl3(N3S2)]2 can be obtained by reaction with gallium trichloride. The crystal structure of PPh4[MᴏCl4(N3S2)] was determ ined by X-ray diffraction (2436 observed reflexions, R = 0.047). Crystal data: orthorhombic, space group Pbca, Z = 8 , a = 1384.3, b = 2092.4, c = 1898.6 pm. The structure consists of PPh4
+ cations and [MᴏCl4(N3S2)]⊕ anions in which the Mo atoms are part of a planar MoN3S2 ring with MoN bond lengths of 183 and 184 pm and nearly equal NS bond lengths (mean value 158 pm). The PPh4
⊕ ions are arranged in centrosymmetric (PPh4
⊕)2 pairs in a manner that normally is encountered with doubly charged anions. The structure found for PPh4[MoCl4(N3S2)] differs from the known monoclinic structures of AsPh4[MoCl4(N3S2)] and AsPh4[WCl4(N3S2)]; an analysis of their packing showed that they form layers of AsPh4
⊕ ions in which three phenyl groups of every AsPh4
⊕ ion are adjacent to phenyl groups of four other AsPh4
⊕ ions
Darstellung und Struktur von Ba2AsSe4(OH) · 2H2O / Preparation and Structure of Ba2AsSe4(OH) · 2H2O
Authors: Kaub Jürgen
Published: March 2015

Ba2AsSe4(OH)·2H2O 1 has been prepared by the reaction of Ba(OH)2 with As2Se3 in aqueous solution and its structure established by X-ray structural analysis. 1 crystallizes in the m onoclinic system , space group Cm (No. 8 ) with a = 8.992(4), b = 9.967(3). c = 6.340(1) A . ß - 104.51(4). Z = 2. M = 718.5, Dber = 4.34 g-cm-3. In the structure there are isolated AsSe4
3- tetrahedra with Cs-symmetry and As-Se bond lengths between 2.303 and 2.329 Å. The Ba2+ ions are coordinated by 6 Se and 3 O atoms
Magnesiumorganische Innerkomplexe, Teil I [1] Bis(dialkylaminoalkyl)- und Bis(alkoxybutyl)magnesium-Verbindungen / Organomagnesium Inner Com plexes, Part I [1] Bis(dialkylaminoalkyl)- and Bis(alkoxybutyl)magnesium Compounds
Authors: Angermund Klaus , Bogdanović Borislav , Koppetsch Gudrun , Krüger Carl , Mynott Richard , Schwickardi Manfred , Tsay Yi-Hung
Published: March 2015

A series of magnesium inner complexes has been prepared by reacting MgH2 (prepared by homogeneous catalysis) with dialkylallyl- and -3-butenylamines and -3-butenylethers in the presence of catalytic amounts of ZrCl4. The monomeric nature of bis(4-methoxybutyl)magnesium has been confirmed by X-ray diffraction.

The analogous syntheses of bis(3-alkoxypropyl)magnesium compounds failed: cleavage of the allyl ether with elimination of propene occurred. This cleavage reaction is accelerated by catalytic amounts of NiCl2 or ZrCl4
The Synthesis of Indeno[l,2:4,5]pyrimido[l,2-a]benzimidazole-13-ones, Indeno[l,2-b]pyrazolo[4,3-e]pyridine-3,5-dione and Related Compounds*
Authors: Metwally Mohamed Abbas , Etman Hassan Ali
Published: March 2015

2-A rylidene-l,3-indaniones (1a and 2b ) reacts with 2-aminobenzimidazole in absolute ethanol, to yield 12,12a-dihydro-12-aryl-13H̱-indeno[1̄,2̄̄̄:4,5]pyrim ido[1,2-a̱]benzimidazole-13-one (2a and 2b). Treatm ent of 2a with PPA gave 15aH̱ -dibenzo[2̄,3̄:4̄,5̄]pentaleno[1̄,6̄:4,5,6]pyrimido- [1,2-a̱]benzimidazole (5). While the condensation of 1c with 3-amino-1-phenyl-2-pyrazolin-5-one in benzene in the presence of PTSA afforded 4-(2-hydroxyphenyl)-2,3a,4,4a-tetrahydro-2-phenylindeno[ 1,2-ḇ]pyrazolo[4,3-e̱]pyridine-3,5-dione (6a). However, the condensation of la with 2-amino-4,6-dihydroxypyrimidine gave the dimeric structure 7. The structures of the hitherto unknown ring systems have been confirmed by PMR, IR and mass spectral data
Benzoatokomplexe des Rutheniums, 1. Mitt. Synthese, Eigenschaften und Kristallstruktur von Ru2(C6H5COO)4(C6H5COOH)2 und Ru2(C6H5COO)5·C6H5COOH / Benzoato Complexes of Ruthenium , Part 1 Synthesis, Properties and Crystal Structure of Ru2(C6H5COO)4(C6H5COOH)2 and Ru2(C6H5COO)5·C6H5COOH
Authors: Spohn Martin , Strähle Joachim , Hiller Wolfgang
Published: March 2015

Ru2(C6H5COO)4(C6H5COOH)2 (1) is formed as main product besides small amounts of Ru2(C6H5COO)5·C6H5COOH (2) by the reaction of Ruthenium (III) acetylacetonate in molten benzoic acid. 1 forms monoclinic black crystals with the space group P21/n and the lattice constants a = 1091.0, b = 1164.1, c = 1526.8 pm, β = 90.53°, Z = 2.2 is obtained as triclinic red needles with the space group P1̄ and the lattice constants a - 1178.4, b = 1605.3, c = 1043.9 pm, a = 99.07°, β = 95.45°, y - 83.22°, Z = 2. Both com pounds exhibit carboxylate bridged dimers [Ru2(C6H5COO)4]n+ (n=0, 1). In case of the isolated Ru(II) dimer 1 two benzoic acid m olecules occupy axial positions and form hydrogen bridges to carboxylate O-atoms. 1 is paramagnetic with two unpaired electrons per dimeric unit corresponding to an electron configuration σ2π4δ2π*3δ* and a bond order of 2 (Ru-Ru = 226.3 pm ). It decomposes at 230 °C to Ru2(C6H5COO)4 and at 350 °C to Ru metal. 2 is polymeric. A benzoate anion functions as bridging ligand between [Ru2(C6H5COO)4]+ dimers. The benzoic acid molecule is weakly associated to the polymer by an H-bridge. A Ru-Ru bond order of 2.5 and a Ru-Ru distance of 227.7 pm are observed.
Reaktionen koordinierter Liganden, III [1]. Stabilisierung von Dimenthyldiphosphen und Menthylphosphiniden als Brückenliganden in Metallcarbonylkomplexen / Reaction of Coordinated Ligands, III [1]. Stabilization of Dim enthyldiphosphene and Menthylphosphinidene as Bridging Ligands in Metal Carbonyl Complexes
Authors: Hinke Anna-Margarete , Hinke Axel , Kuchen Wilhelm , Hönle Wolfgang
Published: March 2015

Reduction of MentPBr2M(CO)5 1 (M = Cr, W) with magnesium in THF yields the diphos­phene complex (CO)5M(Ment)P=P(Ment)M(CO)5 2 as the main product. In addition, a phosphinidene complex, (CO)5M(Ment)PM(CO)5 (3) is also formed. The latter is obtained in larger amounts, if the reaction is carried out in the presence of M(CO)5THF. The proposed structures are confirmed by NMR and UV data as well as - in the case of the chromium compounds (2a, 3a) - by crystal structure analysis. Compound 2a is obtained only as the frans-isomer. The P-P distance in 2a (204.0 pm) indicates a double bond which does not participate in the complex formation. The P-Cr distance in 3a (average: 230.3 pm) is within the low est range found for this element combination. Reaction of 2a with LiAlH4 yields the diphosphane complex (CO)5CrMent(H)P-P(H)MentCr(CO)5 4 as a mixture of “meso” and “rac” diastereomers.
Flüssig-kristalline Verbindungen aus der Thiophenreihe, Teil 3 Azomethine und Vinylene / Liquid Crystalline Compounds in the Thiophene Series, 3 Azomethines and Vinylenes
Authors: Koßmehl Gerhard , Budwill Detlev
Published: March 2015

A number of azomethines and vinylenes, containing 4,4′-biphenylylen and 2,2′-bithienyl-5,5′-diyl units as mesogenic groups has been synthesized and characterized by their elem ental analyses, IR and 1H NMR spectra and studied in relation to their liquid crystalline properties by DTA analysis and visually by their textures microscoping under polarized light. The described compounds are compared with analogous compounds of the benzene series.
A New Dimerization Reaction in Polyphosphoric Acit+
Authors: Balsells Rosa Erra , Portal Carlos R. , Frasca Adolfo R.
Published: March 2015

By heating the o-nitrophenylhydrazone of the propiophenone in polyphosphoric acid medium two dimeric compounds were obtained together with 2-phenyl-3-methyl-7-nitroindole. Some arguments to explain this anomalous reaction are given.
Synthese, Molekül-und Kristallstruktur von 3,5-Dimethyl-2,6-bistrimethylsilyl- 1-thia-2,4,6-triaza-3,5-diborinan-wolframpentacarbonyl/ Synthesis, Molecular and Crystal Structure of 3,5-Dimethyl-2,6-bistrimethylsilyl- 1-thia-2,4,6-triaza-3,5-diborinane-tungstenpentacarbonyl
Authors: Habben Carl , Meller Anton , Noltemeyer Matthias , Sheldrick George M.
Published: March 2015

The am monolysis of 3,5-dim ethyl-2,6-bistrimethylsilyl-1,4-dithia-2,6-diaza-3,5-diborinane leads to 3,5-dim ethyl-2,6-bistrim ethylsilyl-1-thia-2,4,6-triaza-3,5-diborinane, which reacts with tungstenpentacarbonyl · TH F to give the title-com pound. 1H , 11B , 13C, 14N , 29Si NMR spectra, IR and MS data, and the results of an X-ray analysis are reported.
Brom- und Chlorthionitrenkomplexe des Rheniums. Die Kristallstruktur von (PPh4)2 [ReBr4(NS)(NSBr)]·CH2Br2 Bromo- and Chlorothionitrene Complexes of Rhenium The Crystal Structure of (PPh4)2[ReBr4(NS)(NSBr)]·CH2Br2
Authors: Hauck Hans-Günter , Willing Wolfgang , Müller Ulrich , Dehnicke Kurt
Published: March 2015

The thionitrosyl-halothionitrene com pounds (PPh4)2[ReX4(NS)(NSX)]·2 CH2X2, X = Cl or Br, are obtained by nucleophilic ring cleavage of the Re(N2S2) rings of complexes [ReX4(N2S2)]⊖ with PPh4X in CH2X2. (AsPh4)2[ReCl4(NS)(NSCl)] · CH2Cl2 can also be obtained by the reaction of [ReCl4(NSCl)(POCl3)] with S(NSiMe3)2 and subsequent addition of AsPh4Cl. The pyridine complex [ReBr2(NS)(NSBr)(NC5H5)2] · CH2Br2 forms by bromination of the corresponding chloro compound with Me3SiBr. The IR spectra are reported. The crystal structure of (PPh4)2[ReBr4(NS)(NSBr)] · CH2Br2 was determ ined by X-ray diffraction (4158 independent observed reflexions, R = 0.059). Crystal data: a = 1039.7, b - 1232.5, c - 2158.4 pm, α = 81.59, β = 87.05, γ = 77.06°, Z = 2, space group P1̄. The compound consists of PPh4
⊕ ions, CH2Br2 molecules, and anions [ReBr4(NS)(NSBr)]2⊖ in which the rhenium atoms are coordinated by four bromine atoms, one thionitrosyl and one brom othionitrene group. The latter have cis arrangement and ReN bond lengths of 186 pm. W hereas the thionitrosyl group is nearly linear, the R = N = SBr group has an ReNS angle of 165°.
Organoborierung von Alkinylstannanen, XVIII. Neue kondensierte heterocyclische Systeme aus N- und C-lithiierten Azolen und cis- 1,2-organometallisch substituierten Alkenen/ Organoboration of Alkynylstannanes, XVIII. Novel Fused Heterocyclic Systems from N- and C-Lithiated Azoles and cis-1,2-Organometallic Substituted Alkenes
Authors: Kerschl Susanna , Wrackmeyer Bernd
Published: March 2015

Organoboration of dimethyl(chloro)-1-propynylstannane with triethylborane gives (E̲)-2-dimethyl(chloro)stannyl-3-diethylboryl-pent-2-ene (2a) in high yield. Reactions of 2a with N- and C-lithiated azoles (pyrazole, 1-m ethylimidazole, 1-methyl-1,2,4-triazole) lead to the new fused heterocyclic systems 8, 10, 12. In the case of 10 and 12 it was possible to detect (by 11B, 119Sn NM R ) the isomers 9 and 11 which have a zwitterionic structure with an Sn-N linkage. After heating, the compounds 9 and 11 rearrange quantitatively into 10 and 12, respectively. These results show the com petition between boron and tin in 2a as electrophilic centres.
Studies on Heterocyclic Enamines: New Synthesis of Pyrano[2,3-b]pyndine, Pyrano[2,3-d]pyrimidine and Pyrano[2,3-c]pyrazole Derivatives
Authors: Abed Nosrat Mustafa , Ibrahim Nadia Sobhy , Elnagdi Mohamed Helmy
Published: March 2015

A variety of novel pyrano[2,3-d]pyrimidines could be obtained via reaction of ethyl 2-amino- 3-cyano-6-methylpyran-4-carboxylate with a variety of reagents. Evidence for the existance of this pyran derivative as a ring chain tautom er is presented.
Preparation and Crystal Structure of cis-Tetrachlorobis(cyclooctasulfurmonoxide)tin(IV)
Authors: Steudel Ralf , Steidel Jürgen , Sandow Torsten
Published: March 2015

Yellow crystals of cis-[SnCl4(S8 O)2] containing the homocyclic sulfur oxide S8O have been prepared from the com ponents in carbon disulfide at -35 °C. An X-ray structural analysis carried out at -105 °C showed the com pound to be monoclinic, space group P21/n with Z = 4 in a unit cell of dimensions a = 821.2(2) pm, b = 1331.9(4) pm , c = 2071.7(6) pm and β = 91.82(2)°. The structure was refined to a final agreement factor R = 0.038 for 2022 reflections. The tin atom is surrounded by a distorted octahedron of two oxygen atoms in cw-positions and four chlorine atoms in accordance with other oxygen-bonded complexes of SnCl4. The molecular symmetry is approximately C2, and the SS bond lengths in the ligands vary between 201 and 218 pm. Vibrational spectra of [SnCl4(S8O)2] are reported. The title compound is the second example containing S8O as a ligand.
Synthese und spektroskopische Charakterisierung von Metallocen-chloro-selenophenolaten / Synthesis and Spectroscopic Characterization of Metallocene Chloro Selenophenolates
Authors: Köpf Hartmut , Klapötke Thomas
Published: March 2015

Bis(/75-cyclopentadienyl)-chloro-selenophenolatotitanium (IV), Bis(?75-cyclopentadienyl)-chloro-selenophenolatozirconium (IV), Bis(//5-cyclopentadienyl)-chloro-selenophenolatohafnium (IV), Bis(^5-cyclopentadienyl)-chloro-selenophenolatotungsten(IV), Mass Spectra The metallocene chloro selenophenolates C p;M Cl(SeChH 5) (Cp = ^5-C5H 5; M = Ti, Z r, Hf, W) were prepared by reaction of Cp2MCl2 with equivalent am ounts of LiSeC6H 5, obtained from phenylselenol and «-butyllithium, and were characterized by 'H NM R, IR and MS data. The fragmentation behaviour of the Ti and W derivatives is elucidated by observing m etastable transi­ tions in the mass spectra.
Reaktive E =C (p—p)π-Systeme, X Darstellung und Reaktivität von Perfluor-3-phosphapent-2-en / Reactive E = C (p-p)π-Systems, X Preparation and Reactivity of Perfluoro-3-phosphapent-2-ene
Authors: Grobe Joseph , Szameitat Jürgen
Published: March 2015

Perfluoro-3-phosphapent-2-ene F5C2 P =C (F )CF3 (1) has been prepared for the first time by thermal elimination of trimethyltin fluoride Me3SnF from trim ethylstannyl-bis(pentafluoroethyl)- phosphane Me3SnP(C2F5) 2 at 300 °C/10−3 Torr. 1 is found to be less stable than F3CP = CF2 in dilute solution at room temperature, forming several 1,3-diphosphabutane dimers. Reactivity studies accomplished till now include (i) the dienophilicity of 1 in [2+4] cycloaddition reactions with butadiene, 2,3-dim ethylbutadiene, cyclopentadiene, 1,3-cyclohexadiene, 2-methylbutadiene, and 2-methylfuran leading by a concerted mechanism to the Diels-Alder-adducts 2-7 in about 80% yield, (ii) the addition of proton acidic compounds HX (X = OMe, Br, NMe2, NEt2) to the PC double bond affording chiral phosphanes of the type F5C2 P(X)CF(CF3)H [X = OMe (8). Br (9). NMe2 (10). NEt2 (11)]. thus proving a stronger polarity δ+P =δ−C for 1 than for F3CP = CF2. New compounds have been characterized by NMR and MS measurements.
Chemie der Isoblausäure, II Reaktionen von [M(CO)5CNH] (M = Cr, Mo, W) mit Aziridinen: Zyklische Diaminocarbenkomplexe / Chemistry of Hydrogen Isocyanide, II Reactions of [M(CO)5CNH] (M = Cr, Mo, W) with Aziridines: Cyclic Diaminocarbene Complexes
Authors: Fehlhammer Wolf Peter , Bär Eberhard , Boyadjiev Borislav
Published: March 2015

The hydrogen isocyanide complexes [M (CO)5CNH] (M = Cr, Mo, W) have been treated with the aziridines R [xxx] H2 (R = H, R’ = H, Me, Et; R = Me, R’ = H) to give imidazolidin-2-ylidene complexes. The same type of ligand forms on addition of aziridine to the electrophilic isocyanide group in [FpCNPh]+ in the presence of Br−, IR, 1H NMR, 13C NMR and mass spectra of the new compounds are reported.
Inverse Triphenylmethylium-Farbstoffe / Inverse Triphenylmethylium Dyes
Authors: Hellwinkel Dieter , Gaa Heinrich Georg , Gottfried Reiner
Published: March 2015

Keywords

When in the conventional triphenylmethylium dye systems of the crystal violet and malachit green type, 6 and 7, the N̈ -donor and C⊕ -acceptor centers are interchanged , the “Inverse Triphenylmethylium Dye Types” 4 and 5 are obtained , showing very similar colors. The stable models with R = phenyl (8-10) and R = p-tolyl (11-13) were investigated in more detail. The visual observations were supported by the VIS spectra which show ed nearly the same longest wavelength absorption maxim a for corresponding pairs of inverse and conventional dye representatives. The experimental results can be interpreted with a simple HMO -model according to which the longest wavelength absorptions correspond here to transitions of equal energy from weakly bonding to nonbonding and from nonbonding to weakly antibonding molecular orbitals, respectively. On the same basis numerous isoelectronic variants of that dye type can be envisaged. In the N M R -spectra of the new dyes, characteristically increasing deshieldings of nearly all positions are observed in going from the mono- (10+, 13+) through the di- (9++, 12++) to the trications (8+++, 11+++).
Darstellung und Struktur der tert-Butyliminovanadiuni(V)-Verbindungen tC4H9N =V (SR)3 (R = tC4H9, SiPh3) / Synthesis and Molecular Structure of tert-Butyliminovanadium(V) Compounds tC4H9N = V(SR)3 (R = tC4H9, SiPh3)
Authors: Preuss Fritz , Noichl Harald , Kaub Jürgen
Published: March 2015

Thiolato com pounds such as tC4H9N = V(SR)3 (R = tC4H9, SiPh3), iC3H7N = V(StC4H9)3 and tC4H9N = V(OtC4H9)„(StC4H9)3-n (n = 1,2) have been prepared by reaction of im inovanadium (V) chlorides with LiSR. The properties of tC4H9N = V(StC4H9)3 are studied by redistribution and hydrolysis reactions. 1H. 13C, 51V NMR spectra are discussed; the constants of 51V, 14N coupling have been determined. X-R ay diffraction analyses confirm a distorted tetrahedral arrangement of the ligands in the vanadium (V) complexes 5 and 9
Ubergangsmetall-substituierte Acylphosphane und Phosphaalkene, X [1] Phosphaalkenyl-, Mono- und Diacylphosphidokomplexe des Rutheniums Röntgenstrukturanalyse von (η5-C5Me5)(CO)2RuP[C(O)t-Bu]2 / Transition Metal Substituted Acylphosphines and Phosphaalkenes, X [1] Phosphaalkenyl-, Mono- and Diacylphosphido Complexes of Ruthenium X-Ray Analysis of (η5-C5Me5)(CO)2RuP[C(O)t-Bu]2
Authors: Weber Lothar , Bungardt Dagmar , Reizig Klaus , Boese Roland
Published: March 2015

Treatment of (η5-C5Me5)(CO))2 RuP(SiMe3)2 (3) with mesitoyl chloride (MesC(O)Cl) leads to the phosphaalkenyl complex (Z )-(η5-C5Me5)(CO)2Ru-P = C (OSiMe3)(Mes) (4a), whereas with PhC(O)Cl a mixture of the phosphaalkenyl complex 4b and the dibenzoylphosphido complex (η5-C5Me5) (CO)2RuP[C(O)Ph]2 (5b) is obtained. The reaction of 3 with pivaloyl chloride only affords the diacylphosphido complex 5c. The mechanism of these transformations is discussed. The products are characterized by elemental analysis as well as spectroscopic means (IR , 1H-, 13C-, 31P-NMR, MS). For com pound 5c the spectroscopic findings are confirmed by an X-ray structure analysis
(± )-3 ,4 -Dihydro-5-methyl-4-n-alkyl-und -alkenyl-2H-pyrrole aus Pseudomonas putida [1] / (± )-3,4-Dihydro-5-methyl-4-n-alkyl and -alkenyl-2H-pyrroles from Pseudomonas putida [1]
Authors: Hildebrand U. , Budzikiewicz H.
Published: March 2015

From the culture medium of Pseudomonas putida several derivatives of 3,4-dihydro-5-methyl- 2H-pyrrole were isolated differing in the C-4 substituent (unbranched C11, C13 and C15 alkyl and alkenyl groups), the structures of which could be elucidated
The Construction of New Proteins. II. Design, Synthesis and Conformational Studies of Folding Units with βαβ-Topology
Authors: Mutter Manfred , Altmann Karl-Heinz , Vorherr Thomas
Published: March 2015

The design, synthesis and preliminary conformational studies of two polypeptides exhibiting βαβ-type folding topologies are presented. In the design of the model peptides the general concept for the construction of new proteins developed in the preceeding paper was applied. According to this strategy, amphiphilic helices and β-sheets are linked together via hydrophilic loops to attain three-dimensional structures of higher order (‘supersecondary structures’). Com­puter-assisted molecular modelling served as a valuable tool for minimizing conformational con­straints within the molecules. The 38-residue peptide MI was synthesized using polyethylene glycol (PEG) as solubilizing polymeric support (‘Liquid-Phase synthesis'). Conformationally in­duced changes in the physico-chemical properties of the growing peptide chain stressed the significance of conformational effects in peptide synthesis reported earlier. Similar observations were made during the solid-phase synthesis of the 35-peptide MII. CD and IR spectroscopic studies revealed a high degree of secondary structure for both folding units. The present data strongly support the adoption of a three-dimensional structure for both models.
Transition Metal Squarates, II On the Structure of Cubic (MC4O4·2H2O)3CH3COOH·H2O(M=Zn2+,Ni2+)[1]
Authors: Weiss Armin , Riegler Eugen , Robl Christian
Published: March 2015

The isotypic compounds (MC4O4·2 H2O)3·CH3COOH·H2O(M=Zn2+,Ni2+) crystallize in the cubic space group Pn3n. The 3-dimensional framework structure contains cavities, which may be filled with CH3COOH · H2O . The metal ions are coordinated almost octahedrally by two water molecules and four oxygen atoms of four C4O4
2- dianions. Thus the squarate dianions act as fourfold monodentate ligands. Strong hydrogen bonding between H2O and C4O4
2- has to be assumed.
Übergangsmetallquadratate, III Über die trikline Käfigstruktur des (MC4O4·2 H2O)3·CH3COOH·H2O(M = Zn2+, Mn2+)/Transition Metal Squarates, III On the Triclinic Cage Structure of (MC4O4·2 H2O)3-CH3COOH·H2O(M = Zn2+, Mn2+)
Authors: Weiss Armin , Riegler Eugen , Robl Christian
Published: March 2015

The isostructural compounds (MC4O4·2 H2O)3·CH3COOH·H2O (M=Zn2+,Mn2+) crystallize in the triclinic space group P1̄, if grown in solution of high ionic strength. The structural features are similar to those in the cubic phase. Correspondingly CH3COOH·H2O can be trapped in cage­ like cavities, formed by the 3-dimensional framework o f M2+ and C4O4
2- . The metal ions are coordinated in a distorted octahedral fashion. The squarate dianions act as four-fold monodentate ligands.
Komplexe mit substituierten 2,5-Dihydroxy-p-benzochinonen: ZnC6(NO2)2O4·2 H2O/Complexes with Substituted 2,5-Dihydroxy-p-benzochinones: ZnC6(NO2)2O4·2 H2O
Authors: Robl Christian , Weiss Armin
Published: March 2015

ZnC6(NO2)2O4 · 2 H2O was grown in aqueous silicagel. It crystallizes monoclinically (space group I2/c). Zn2+ has CN 6 . It is surrounded in a distorted octahedral fashion by 2 water molecules in cis -position and 4 oxygen atoms of the bis-chelating [C6(NO2)2O4]2- ions. Thereby infinite corrugated chains are formed consisting of Zn2+ and the nitranilate dianions. These chains are interlinked by hydrogen bonds between H2O and the NO2 groups. The NO2 groups are twisted against the ring plane. The bond lengths in the dianion are typical of completely delocalized π-electrons.
Borylierte Carbodiimide
Authors: Einholz Wolfgang , Haubold Wolfgang
Published: March 2015

The borylated carbodiimides 3 a, 3b and 4 can be synthesized by reaction of the 2-chloro-1,3,2-diazaborolidines 2a, 2b with Me3Si -N = C = N -SiMe3 (1) or Me3Si -N = C = N -tBu respectively. In the reaction of the non cyclic haloboranes R2BHal (R = Ph, Me, Me2N) 2c -e with 1 R3B is formed and for R = Me, Me2N polymeric (RBNCN)n is obtained, whilst the spectroscopically identified intermediate products only in the case of R = Ph can be isolated. The chloroborolane 2f leads to the polymeric diborylated carbodiimide 3f, probably due to intermolecular B -N-coordination. H2N -CN forms with 9-BBN the monoborylated cyanamide 8 .
Sr3In2P4 und Ca3ln2As4, Zintlphasen mit Bänderanionen aus kanten-und eckenverknüpften InP4- bzw. InAs4-Tetraedern/ Sr3In2P4 and Ca3In2As4, Zintl Phases with Strings of InP4 and InAs4 Tetrahedra, Resp., Sharing Edges and Corners
Authors: Cordier Gerhard , Schäfer Herbert , Stelter Michael
Published: March 2015

The new compounds Sr3In2P4 and Ca3In2As4 crystallize in the orthorhombic system , space group Pnnm (No. 58), with the following lattice constants:

Sr3In2P4: a = 1632.3(6), b = 682.8(3), c = 428.9(2);

Ca3In2As4: a = 1621.2(6), b = 659.5(3), c = 430.6(2).

In the anionic partial lattice InP4 (InAs4) tetrahedra are connected by common edges and corners and form (InP2
3-)n ((In As2
3-)n) strings of alternating four-membered and eight-membered rings.
Kristallstruktur von β-VCl2(N3S2). Synthese und Kristallstruktur von [VCl(N3S2)(Pyridin)2]2·2 CH2Cl2, einem Cyclothiazenokomplex mit Vanadium(IV)/Crystal Structure of β-VCl2(N3S2). Synthesis and Crystal Structure of [VCl(N3S2)(pyridine)2]2·2 CH2Cl2, a Cyclothiazeno Complex with Vanadium (IV)
Authors: Christophersen Ruth , Willing Wolfgang , Müller Ulrich , Dehnicke Kurt
Published: March 2015

β-VCl2(N3S2) was obtained by sublimation. It represents a new modification compared to the known α-VCl2(N3S2) which can be obtained from solution. Its crystal structure was determined by X-ray diffraction (864 observed reflexions, R = 0.034). Crystal data: triclinic, space group P1̄, Z = 2, a = 570.0, b = 779.9, c = 735.3 pm , α = 90.85°, β = 108.26°, y = 98.77°. Both modifications consist of polymer chains in which the vanadium atoms are linked alternatively by chloro and nitrogen bridges. The packing of the chains is rather similar, the only difference being that in β-VCl2(N3S2) the chains are rotated by 11° as compared to the orientation in α-VCl2(N3S2). The difference of the two modifications also shows up in the slightly different IR spectra.

By reduction of VCl2(N3S2), dissolved in CH2Cl2/pyridine, with H2S, zinc or PPh3, the cyclothiazeno complex [VCl(N3S2)(pyridine)2]2·2 CH2Cl2 was obtained. It crystallizes in the monoclinic space group P 21/c, Z = 4, a = 1010.4, b = 917.3, c = 1967.8 pm, β = 103.03° (structure determination with 649 observed reflexions. R = 0.081). In this vanadium(IV) compound the metal atoms are part of planar VN3S2 rings as found in the VCl2(N3S2) modifications. The two vanadium atoms of the centrosymmetrical dimer are linked via one nitrogen atom of each of the VN3S2 rings; the resulting V2N2 ring is coplanar with the two VN3S2 rings.
Synthese und Kristallstruktur von W2[OC(CF3)2NMe2]2(NMe2)4 / Synthesis and Crystal Structure of W2[OC(CF3)2NMe2]2(NMe2)4
Authors: Roesky Herbert W. , Bertel Norbert , Edelmann Frank , Herbst Regine , Egert Ernst , Sheldrick George M.
Published: March 2015

The reaction of W2(NMe2)6 with hexafluoroacetone (HFA) yields W2[OC(CF3)2NMe2]2(NMe2)4, an orange solid, which was characterized by mass spectra, 1H, 13C, 19F NMR spectra and an X-ray structure analysis. The compound contains a W=W triple bond of 230.1(1) pm.
Darstellung und Kristallstrukturen von [(η5-C5H5)2Ti(P(CH3)2Si(CH3)3)Cl) und [Ti(η5-C5H5)2(μ2-P(CH3)2)]2 / Synthesis and Crystal Structure of [(η5-C5H5)2Ti(P(CH3)2Si(CH3)3)Cl) and [Ti(η5-C5H5)2(μ2-P(CH3)2)]2
Authors: Payne Robert , Hachgenei Johannes , Fritz Gerhard , Fenske Dieter
Published: March 2015

(η5-C5H5)2TiCl2 reacts with P(CH3)2(Si(CH3)3) to form the paramagnetic complex [(η5-C5H5)2Ti(Cl)P(CH3)2Si(CH3)3] (1). In 1 Ti is coordinated by two (η5-C5H5), and a Cl-ligand. In addition Ti is bound to the P-atom of a P(CH3)2(Si(CH3)3) ligand. Treatment of 1 with Na/Hg affords the dinuclear paramagnetic complex [Ti(η5-C5H5)2(μ2-P(CH3)2)]2 (2). 2 contains two Ti(η5-C5H5)2 units. Each Ti is bound to the P-atoms of the μ2-P(CH3)2-ligands. The Ti-Ti- contact (391.8 pm) does not correspond to metal-metal bonding.
Synthese von 4,4,5,5-Tetramethyl-3-oxid- 2-ferrocenyk-imidazolin-1-oxyl / Synthesis of 4 ,4 ,5 ,5-Tetramethyl-3-oxide- 2-ferrocenyl-imidazoline-1-oxyl
Authors: Owtscharenko Wiktor I. , Huber Wolfgang , Schwarzhans Karl E.
Published: March 2015

A nitronylnitroxide derivative of ferrocene has been prepared by interaction of ferrocene aldehyde with 2,3-bis(hydroxylamino)-2,3-dimethylbutane followed by oxidation with lead(IV ) oxide.
Phasenbeziehungen im System Nain—Sn und die Kristallstrukturen der intermediären Verbindungen NaInSn2 und NaInSn4 / Phase Relations in the System Naln—Sn and the Crystal Structures of the Intermediate Compounds NaInSn2 and NaInSn4
Authors: Blase Wolfgang , Cordier Gerhard , Kniep Rüdiger , Schmidt Roswitha
Published: March 2015

The quasibinary system Naln-Sn contains the intermediate phases NayInySn, Na9In9Sn2, NalnSn, Na2In2Sn3, NaInSn2 and NaInSn4. With the exception of Na2In2Sn3 (stable only between 134°C and 365°C), crystals of the ternary compounds were grown from the melt and were investigated by single crystal X-ray methods (Na9In9Sn: a = 2287.7(8) pm, F43m; Na9In9Sn2: a = 1662.4(7), c = 983.9(5) pm, P6/mmm; NaInSn: a = 486.1(2), c = 775.7(4) pm, P63/mmc; NaInSn2: a = 627.9(3), b = 654.3(3), c = 1139.6(5) pm, P212121; NaInSn4: a = 654.6(4), c = 531.6(6) pm, I4/mcm). The crystal structure of NaInSn is a representative of the Zintl-phases. with the [InSn]⁻-partial structure in a wurtzite-type arrangement. The crystal structures of NaInSn4 and NaInSn2 have been determined (R = 0.038 and 0.062, respectively). The crystal structure of NaInSn2 contains In and Sn atoms in a helical arrangement (six atoms per turn) along the α-axis direction. Interatomic bonds between neighbouring helices complete a distorted [2+2]-tetrahedral environment for every In/Sn position. The compound can be classified in terms of the Zintl concept.

NaInSn4 is an isotype of the intermetallic phase Al2Cu. By this, the chemical and structural series NaInSn → NalnSn2 → NaInSn4 represents a change from Zintl-phases to an intermetallic phase.
Zur Reaktion von [η5-CpMCl4] (M = Nb, Ta) mit E(SiMe3)2 (E = S, Se) Die Kristallstrukturen von [Cp8Ta6S10], [Cp3Ta3S7Cl2], [Cp4Ta4S13] und [Cp3Nb3Se5Cl2] / Reaction of [η5-CpMCl4] (M = Nb, Ta) with E(SiMe3)2 (E = S, Se) The Crystal Structures of [Cp8Ta6S10][TaSCl5], [Cp3Ta3S7Cl2], [Cp4Ta4S13] and [Cp3Nb3Se5Cl2]
Authors: Fenske Dieter , Maué Paul G.
Published: March 2015

[η5-CpMCl4] (M = Nb, Ta) reacts with E(SiMe3)2 (E = S, Se) to form different multinuclear clusters. The cation [Cp8Ta6S10]2+ (1) consists of a planar Ta2S2-ring of which each Ta is coordi-nated to two Cp2TaS2-fragments. [Cp4Ta4S13] (3) can be derived from [Cp3Ta3S7Cl2] (2) by addition of a CpTaS6-unit to a triangle of Ta-atoms bridged by S- and S2-ligands. The niobium atoms in [Cp3Nb3Se5Cl2] (4) arrange in a chain structure with Nb coordination numbers varying from 4-6.
Synthese und Kristallstruktur von 2-Trimethylsilyl-1,3-bistrimethylsilylimino-1,3-dihydro-isoindol sowie die Kristallstruktur von Hexakis(trimethylsilyl)-1,4-benzdiamidin / Synthesis and Crystal Structure of 2-Trimethylsilyl-1,3-bis-trimethylsilylimino-1,3-dihydro-isoindole and the Crystal Structure of Hexakis(trimethylsilyl)-1,4-benzdiamidine
Authors: Weller Frank , Schmock Fritjof , Dehnicke Kurt
Published: March 2015

2-Trimethylsilyl-1,3-bis-trimethylsilylimino-1,3-dihydro-isoindole, C8H4N3(SiMe3)3 (2), has been prepared by the reaction of 1,2-benzodinitrile with LiN(SiMe3)2, followed by treatment with ClSiMe3. 2 forms yellow crystals, which were characterized by a crystal structure determination, as was the known hexakis(trimethylsilyl)-1,4-benzdiamidine, {[(SiMe3)2N](SiMe3N)C-C6H4-C(NSiMe3)[N(SiMe3)2]}) (1).

1: space group P1, Z = 1̄,2520 observed independent reflexions, R = 0.052. Lattice dimensions (19°C): a = 662.7(1); b = 1088.3(1); c = 1417.4(2) pm; α = 76.60(1)°; β = 87.33(1)°; γ = 73.90(1)°. 1 forms monomeric centrosymmetric molecules with the amidino groups in 1,4-position of the C6H4 ring. The CN distances are 127.1(3) and 141.3(3) pm, respectively, corresponding to C=N̅-SiMe3 and C-N̅(SiMe3)2 moieties.

2: space group P212121, Z = 4, 1960 observed independent reflexions, R = 0.058. Lattice dimensions (20°C): a = 643.0(1); b = 1477.4(1); c = 2414.4(2) pm. 2 forms monomeric molecules with a planar isoindole skeleton with different Si-N-bond lengths of the SiMe3 groups in 2-position (180.2(5) pm) and in 1,3-positions (171.4(5); 170.9(9) pm).
Photophysics of Ceramic Luminophores. Zeolite-Based Luminophores of the Types Zn2SiO4: Mn and (CdO)2B2O3: Mn
Authors: Hesse K. , Gliemann G. , Kiss A. , Kleinschmit P. , Völker W.
Published: March 2015

The emission spectra (at T = 10 K and 296 K) and the excitation spectra (at T = 295 K) of zeolite-based luminophores of the types Zn2SiO4:Mn and (CdO)2B2O3:Mn show the characteristics of Mn2+ in tetrahedral and octahedral surroundings, respectively, as well as additional features due to impurities and/or structural defects of the host crystal. The ZnSiO4⁻type phosphor exhibits photostimulated emission, which can be assigned to trap states of the silicate host.
2,2-Diethoxy-1-ethendiazonium-hexachloroantimonat: Ein vielseitiger Synthesebaustein für 5- und 6-gliedrige N-Heterocyclen Kristall- und Molekülstruktur von 5′-Phenyl-3′-(2-phenyl-6H-1,3,4-oxadiazin-5-yl)spiro [isobenzofuran-1(3H),2′ (3′H)-[1,3,4]-oxadiazol]-3-on [1] / 2,2-Diethoxy-1-ethenediazonium Hexachloroantimonate: A Versatile Building Block for the Synthesis of 5- and 6-Membered N-Heterocycles Crystal and Molecular Structure of 5′-Phenyl-3′-(2-phenyl-6H-1,3,4-oxadiazine-5-yl)spiro[isobenzofuran-1(3 H),2′(3′ H)-[1,3,4]-oxadiazol]-3-one [1]
Authors: Saalfrank Rolf W. , Weiß Bernhard , Wirth Uwe , Peters Karl , Schnering Hans Georg von
Published: March 2015

Reaction of 2.2-diethoxy-1-ethenediazonium salt la with primary amines 5 yields 1-alkyl-1 H1,2,3-triazoles 7. With hydrazide 8 diazonium salt la reacts completely differently. The thus formed 2′-[2-phenyl-4H-1,3,4-oxadiazine-5(6H)-ylidene]benzohydrazide (9) can be annellated under elimination of water or transformed by reaction with phosgene, thionyl chloride and phthalic acid dichloride respectively to give the heterocycles 10-13.
Beiträge zur Chemie des Phosphors, 196 Synthese und Eigenschaften der Organyltris(phosphino)silane RSi(PH2)3 (R = Me, Et, i-Pr, Ph) / Contributions to the Chemistry of Phosphorus, 196] Synthesis and Properties of the Organotris(phosphino)silanes RSi(PH2)3 (R = Me, Et, i-Pr, Ph)
Authors: Baudler Marianne , Scholz Guido , Oehlert Wolfgang
Published: March 2015

The new organotris(phosphino)silanes RSi(PH2)3 (R = Me (1), Et (2), i-Pr (3), Ph (4)) have been synthesized by reaction of the appropriate chlorosilanes RSiCl3 with LiAl(PH2)4 in the molar ratio 1:0,75. With an excess of RSiCl3 the mixed chlorophosphinosilanes RSi(PH2)Cl2 and RSi(PH2)2Cl have also been obtained, the 31P NMR data of which are reported. The compounds 1-4 could be isolated in pure form and have been fully characterized by elemental analyses and various spectroscopic methods
Clusteraufbau durch Photolyse von R3PAuN3, III / Cluster Synthesis by Photolysis of R3PAuN3, III [1]
Authors: Beuter Georg , Strähle Joachim
Published: March 2015

Photolysis of a mixture of Ph3PAuN3 with Fe(CO)5, Fe2(CO)9 or Fe3(CO)12 in THF yields [(Ph3PAu)5Fe(CO)3]+ (1) which crystallizes with PF6~ as counterion as air stable, yellow platelets in the space group P21/c: a = 2230.0(7), b = 1655.0(6), c = 2462.7(8) pm, β = 94.04(5)°, Ζ = 4. The cationic Au5Fe cluster forms a bicapped FeAu3 tetrahedron with almost equal Fe-Au distances of 259.0 to 265.1 pm to all five Au atoms. Due to the local symmetry C3 of the Fe(CO)3 group two v(CO) at 1880 and 1930 cm-1 are observed. Co-photolysis of Ru3(CO)12 and Ph3PAuN3 does not result in a cleavage of the Ru3 cluster. Bridging μ-AuPPh3 and μ-NCO groups substitute two CO ligands to form Ru3(CO)10 (μ-AuPPh3)(μ-NCO) (2)
Eine 15N-NMR-untersuchung einiger trimethylstannylhydrazine / A15N-NMR study of some trimethylstannylhydrazines
Authors: Wrackmeyer Bernd , Gasparis-Ebeling Theo , Nöth Heinrich
Published: March 2015

The trimethylstannylhydrazines (Me3Sn)2N-NMe2 (1), Me3Sn(Me)N-N(Me)SnMe3 (2), (Me3Sn)2N-N(Me)SnMe3 (3), and (M e3Sn)2N-N(Ph)SnMe3 (4) have been studied by δ15N NMR at natural abundance. A correlation between δ15N of hydrazines and δI5N of corresponding am ines (replacement of one N-atom by the CH-unit) is proposed in order to estimate δI5N values and to support the non-trivial assignment of 15N resonances of hydrazines. Geminal coupling constants 2J(119SnN 15N) have been observed for the first time. Their relative magnitude is related to the probability of the N-Sn bond being in cis-position with respect to the orientation of the lone electron pair at the 15N nucleus in the 119Sn-N-15N fragment. Treatment of 4 with phenylacetylene causes non-selective cleavage of the Sn-N bonds, leading to the trim ethylstannylhydrazines 5 and 6 which have been characterized by 119Sn and 15N NMR spectroscopy in solution
Die Jahn-Teller-Verzerrung in den Kristallstrukturen der Dinatrium-Tetrafluorometallate Na2CuF4 und Na2CrF4 / The Jahn-Teller Distortion in the Crystal Structures of the Disodium-Tetrafluorometallates Na2CuF4 and Na2CrF4
Authors: Babel Dietrich , Otto Michael
Published: March 2015

The crystal structures of the isotypic monoclinic fluorides Na2CuF4 (a = 326.7(1), b = 937.0(2), c = 561.2(1) pm, β = 92.49(1)°; V = 171.63 x10-30 m3) and Na2CrF4 (a = 334.8(1), b = 954.9(2), c = 566.5(3) pm, β = 92.85(3)°; V = 180.89 × 10-30 m3) have been redetermined by single crystal X-ray methods. The compounds are Jahn-Teller distorted variants of the orthorhombic Sr2PbO4type (space group Pbam) and crystallize with Z = 2 in space group P21/c, a subgroup of Pbam. They form a chain structure of edge-sharing octahedra which are strongly elongated. The following distances were obtained: Cu-F = 190.4/193.8/235,7(2) pm and Cr-F = 199.1/199.7/241.7(4) pm. The geometry is compared to that of the corresponding distorted rutile type difluorides; relations to further compounds are discussed.
Komplexbildung in TlCl3- und Chlorothallat(III)-Schmelzen / Complexation in TlCl3 and Chlorothallate(III) Melt Systems
Authors: Brockner Wolfgang , Alexiou Vassilios , Somer Mehmet
Published: March 2015

TlCl3 and TlCl3-TlCl mixtures have been prepared and investigated by Raman spectroscopy in the solid and molten state. Already at 50°C TlCl3 starts to decompose according to TlCl3 → TlCl + Cl2. TlCl generated reacts with TlCl3 to give TlCl4
-, Tl2Cl7~ and possibly Tln
IIICl3n+1
- units with n ≧ 2, respectively. Molten TlCl3, can be described best by the equilibrium TlCl4
- + TlCl3 ⇄ Tl2Cl7
-.

In solid TlCl3-TlCl mixtures the following species could be identified Tl3(TlIIICl6), Tl3
1(Tl2
IIICl9) and TlCl4). TlCl4
- and TlCl5
2- complex units dominate in the molten state. In the melt, species are in dynamic coupled equilibria depending on temperature and stoichiometry.
Synthese von zweikernigen Triazenido- und Pentaazadienidokomplexen des einwertigen Silbers. Kristallstruktur von [Ag(MeOC6H4N3C6H4OM e)]2· 2/3 Py, [Ag(MeOC6H4N5C6H4OMe)]2 und [Ag(EtOC6H4N5C6H4OEt)]2 · Py / Dimeric Triazenido and Pentaazadienido Complexes of Monovalent Silver. Synthesis and Structure of [Ag(MeOC6H4N3C6H4OM e)]2· 2/3 Pyridine, [Ag(MeOC6H4N5C6H4OMe)]2 und [Ag(EtOC6H4N5C6H4OEt)]2 · Pyridine
Authors: Hartmann Edmund , Schmid Raimund , Strähle Joachim
Published: March 2015

[Ag(MeOC6H4N3C6H4OMe)]2 (1) is formed in THF from AgNO3 , and the triazenide anion, as obtained from the corresponding triazene and Na. 1 crystallizes from pyridine in the form of orange-yellow , air stable crystals with the com position 1·2/3 C5H5N: space group P 1̅ with a = 1468.0(5), b = 1514.1(6), c - 1316.1(3) pm, a = 113.45(3)°, β = 1 1 4 .8 1 (2 )°, γ = 66.78(3)°, Z - 3. The triazenide ion functions as a bridging ligand forming planar (AgN3)2 heterocycles. The unit cell contains two symmetry-independent dinuclear complexes, one of which is centrosymmetrical. The short Ag -Ag distances of 268.0 and 269.8 pm suggest Ag -Ag bonding. The pentaazadienido complexes Ag(RN5R) with R = p -MeO - C6H4 (2), p -EtO - C6H4 (3), p-Cl -C6H4 (4), p -F -C6H4 (5), are obtained from saturated solutions of the pentaazadiene in conc. NH3 and AgNO3 , as explosive, red precipitates which are stable in air. Crystals of 2 and 3 · C5H5N are obtained from pyridine. 2 crystallizes in the monoclinic space group P21/c: a - 583.7(6), b = 1705.1(9), c = 1489.6(9) pm. β = 96.2(1)°, Z = 2; 3 · C5H5N is triclinic (space group P 1̅) with a = 1160.4(4). b = 1671.0(6), c = 509.0(1) pm. a = 97.51(2)°, β = 97.36(2)°, γ = 81.51(3)°, Z = 1. The complexes 2 and 3 are dinuclear with the pentaazadienide ion as a (N1)-η1,(N5)-η1 bridging ligand in 2 and a (N1)-η1, (N3)-η1 bridging ligand in 3. The bridging mode in 3 results in a short Ag -Ag contact of 283.44 pm. The Ag -N distances range from 210.8 to 215.7 pm in 1 and from 215.0 to 220 pm in (2) and (3).
Strukturchemie ungesättigter Siliciumverbindungen: Kristall- und Molekülstrukturen des stabilen Silanimins ′Bu2Si=N—Si′Bu3 und von Silanimin-Donoraddukten (Donor = Tetrahydrofuran, Benzophenon) / Structural Chemistry of Unsaturated Silicon Compounds: Crystal and Molecular Structures of the Stable Silaneimine ′Bu2Si=N—Si′Bu3 and of Silaneimine Donor Adducts (Donor = Tetrahydrofuran, Benzophenone)
Authors: Reber Gabriele , Riede Jürgen , Wiberg Nils , Schurz Klaus , Müller Gerhard
Published: March 2015

The structure of the first stable silaneimine ′Bu2Si=N—Si′Bu3 (1) (i.e. a compound containing a silicon nitrogen double bond) has been determined by X-ray crystallography (monoclinic, space group P21/n, a = 8.962(1), b = 18.361(1), c = 14.658(1) Å, β = 90.98(1)°, V = 2411.6 Å3.Z = 4, wR = 0.043, w = 1/σ2(Fo) for 208 refined parameters and 2610 observed structure factors. It is monomeric in the solid state and has a nearly linear Si=N—Si skeleton (Si—N—Si 177.8(2)°) with drastically different Si=N and Si—N bond lengths (1.568(3) and 1.695(3) A, respectively). The benzophenone adduct of ′Bu2Si=N—Si′Bu3 and the tetrahydrofuran (THF) adduct of the closely related silaneimine Me2Si=N—Si′Bu3 contain the donor molecules being coordinated exclusively to the unsaturated silicon atoms, which adopt a distorted tetrahedral coordination geometry upon coordination with characteristically elongated Si=N double bonds. The solid state structure of the benzophenone adduct strongly suggests that [2+2] cycloadditions of Si=N double bonds with aldehydes or ketones proceed in a non-concerted manner via prior formation of donor-Si bonds.

((THF) • Me2Si=N—Si′Bu3 (2): P21/n, a = 18.480(4), b = 14.209(2), c = 18.683(5) Å, β = 115.11(2)°, V = 4442.2 Å3, Z = 8, wR = 0.094 for 397 parameters and 3432 observables; (Ph2C=O) · ′Bu2Si=N—Si′Bu3 (3): P21,/n, a = 13.247(2), b = 15.689(2), c = 17.073(2) Å. β = 110.53(1)°, V = 3323.0 Å3, Z = 4, wR = 0.039 for 379 refined parameters and 3789 observables.)
Catechoyl-Dipeptides as Leucine Aminopeptidase Inhibitors
Authors: Nakonieczna Łucja , Pastuszak Juliusz J. , Chimiak Andrzej
Published: March 2015

Several 2,3- (and 3,4)-dihydroxybenzoyl-dipeptides (5) have been obtained as new ligands able to interact with therapeutically important metalloproteases. Some of them appeared to be strong inhibitors of leucine aminopeptidase [EC 3.4.11.1].
Intramolekulare Cycloadditionen mit Isobenzofuranen VII [1]. Synthese von rac. Thiafarfugin A, einem Thiophenanalogon eines natürlich vorkommenden Furanosesquiterpens / Intramolecular Cycloaddition Reactions with Isobenzofurans VII [1]. Synthesis of rac. Thiafarfugin A, a Thiophene Analogue of a Naturally Occurring Furanosesquiterpene
Authors: Schöning Axel , Friedrichsen Willy
Published: March 2015

The synthesis of Thiafarfugin A via an intramolecular Diels-Alder reaction of a 6-alkenyl thieno[2,3-c]furan is described.
Notizen: Molekül- und Kristallstruktur des 2,4-Bis(diisopropylamino)-3-phenyl-1,3,2,4-thiazadiboretidins / Crystal and Molecular Structure of 2,4-Bis(diisopropylamino)-3-phenyl-1,3,2,4-thiazadiboretidine
Authors: Habben Carl D. , Noltemeyer Mathias
Published: March 2015

The title compound, C18H33B2N3S, isolated from the reaction of 3,5-bis(diisopropylamino)-1,2,4,3,5-dithiazadiborolidine with elemental sodium, crystallizes in space group P1̅ with cell constants a = 1034.3(6), b = 1230.4(8), c = 1728.5(12) pm, α = 97.50(6), β = 97.95(5), γ = 90.17(5)° and Z = 4. X-ray structure refinement converged at R = 0.087, wR = 0.085, w-1 = σ2(F0) + 0.004 Fo
2. The fourmcmbered ring B2NS is planar, the angle B—S—B being 70°.