bluuebunny/crossref_metadata_2025_split huggingface dataset:
Einfache Synthese von 2,2-Diethoxy-2,5-dihydrofuranen, 2(5 H)Furanonen und 2-Ethoxy-furanen.Kristall-und Molekülstruktur eines Barrelenon Diels-Aider Produktes [1] / Convenient Synthesis of 2,2-Diethoxy-2,5-dihydrofurans, 2(5 H)Furanones and 2-Ethoxyfurans.Crystal and Molecular Structure of a Barrelenone Diels-Alder Product [1]
Authors: Saalfrank Rolf W. , Hafner Wieland , Markmann Joachim , Welch Andreas , Peters Karl , Schnering Hans Georg von 
Published: February 2015

Abstract
Reaction of 1,2-hydroxyketones 5 with (2,2-diethoxyvinylidene)triphenylphosphorane (2) or (2,2-diethoxyvinyl)triphenylphosphonium tetrafluoroborates 6 yields the 2,2-diethoxy- 2.5-dihydrofurans 9. Depending on the reaction conditions used, the orthoesters 9 can be hydrolized to give 2(5 H)furanones 10 and 2-ethoxyfurans 11, respectively. 4,5-Dimethyl- 5.6-dihydro-2-pyranone (20) and 8-methoxycoumarin (23) are prepared, starting from (2,2-diethoxyvinyl)triphenylphosphonium tetrafluoroborate (6 a) and 1-hydroxy-2-methyl- 3-butanone (16) or 2-hydroxy-3-methoxy-benzaldehyde (21). The 2-ethoxyfuranes 11 readily undergo Diels-Alder reactions with 2-chloracrylonitrile (24), maleic anhydride (26), N-phenyl-1,2,4-triazoline-3,5-dione (28) and dimethyl acetylenedicarboxylate (30) to give the corresponding Diels-Alder products 25, 27, 29 and 31, respectively. Contrary to 2-ethoxyfuran 11b , 11a reacts with two equivalents of acetylene 30, to yield barrelenone 34. The structure of 34 unequivocally is established by X-ray structure analysis.
μ2-Chlorokomplexe von Succinimid und N-Chlorsuccinimid. Die Kristallstrukturen von PPh4[Cl(Succinimid)2], PPh4[[Cl(N-Cl-Succinimid)2] und N-Chlorphthalimid / μ2-Chloro Complexes of Succinimide and N-Chlorosuccinimide. The Crystal Structures of PPh4[Cl(Succinimide)2], PPh4[Cl(N-Cl-Succinimide)2] and N-Chlorophthalimide
Authors: Ghassemzadeh Mitra , Harms Klaus , Dehnicke Kurt , Magull Jörg 
Published: February 2015

Abstract
The donor-acceptor complexes PPh4[Cl(succinimide)2] and PPh4[Cl(N-chlorosuccinimide)2] have been prepared by reactions of PPh4Cl with succinimide and N-chlorosuccinimide, re­ spectively. in acetonitrile solutions. The complexes have been characterized by IR spectros­ copy and by crystal structure determinations. The crystal structure of N-chlorophthalimide has also been solved.
(Hydroxymethyl)diphenyl(piperidinoalkyl)silane des Typs (HOCH2)(C6H5)2Si(CH2)nNC5H10(n=2,3) und deren Methoiodide: Synthese, Struktur und antimuscarinische Eigenschaften / (Hydroxymethyl)diphenyl(piperidinoalkyl)silanes of the Type (HOCH2)(C6H5)2Si(CH2)nNC5H10(n = 2,3) and their Methiodides: Synthesis, Structure and Antimuscarinic Properties
Authors: Tacke Reinhold , Kropfgans Martin , Tafel Andrea , Wiesenberger Frank , Sheldrick William S. , Mutschler Ernst , Egerer Hansjörg , Rettenmayr Nikola , Gross Jan , Waelbroeck Magali , Lambrecht Günter 
Published: February 2015

Abstract
Starting from (MeO)3SiCH2Cl (10) and Ph2(H)SiCH2OH (16), respectively, the (hydroxymethyl)diphenyl(piperidinoalkyl)silanes (HOCH2)Ph2Si(CH2)2NC5H10 (6) and (HOCH2)Ph2Si(CH2)3NC5H10 (8) have been synthesized [10→Ph2(MeO)SiCH2Cl (11)→Ph2(CH2=CH)SiCH2Cl (12)→Ph2(CH2=CH)SiCH2OAc (13)→Ph2(CH2=CH)SiCH2OH (14)→Ph2(CH2=CH)SiCH2OSiMe3 (15)→6; 16→Ph2(H)SiCH2OSiMe3 (17)→8; NC5H10 = piperidino]. N-Quaternization of 6 and 8 with MeI gave the corresponding methiodides 7 and 9, respectively. As shown by IR-spectroscopic studies, compounds 6 and 8 form intramolecular O-H···N hydrogen bonds in solution (CCl4). In the crystal, 6 (space group Pna21; two crystallographically independent molecules) also forms intramolecular O-H···N hydrogen bonds whereas 8 (space group P1̅) forms intermolecular O-H···N hydrogen bonds leading to the formation of centrosymmetric dimers (single-crystal X-ray diffraction studies). The (hydroxymethyl) silanes 6-9 and the related silanols (HO)Ph2Si(CH2)2NC5H 10 (sila-pridinol; 1), sila-pridinol methiodide (2), (HO)Ph2Si(CH2)3NC5H10 (sila-difenidol; 3) and sila-difenidol methiodide (4) were investigated for their antimuscarinic properties. In functional pharmacological experiments as well as in radioligand competition studies, all compounds behaved as simple competitive antagonists at muscarinic M1-, M2-, M3- and M4-receptors. In general, the silanols 1-4 displayed higher receptor affinities (up to 100-fold) than the corresponding (hydroxymethyl) silanes 6-9 . In the (hydroxymethyl)silane series, compound 7 was found to be the most potent muscarinic antagonist [pA2/pKi= 8,71/8,6 (M1), 8,23/7,8 (M2), 8,19/7,8 (M3); pKi = 8,2 (M4)]. In the silanol series, the related compound 2 showed the most interesting antimuscarinic properties [pA2/pKi = 10,37/9,6 (M1), 8,97/8,8 (M2), 9,08/8,8 (M3); pKi = 9,4 (M4)].
1,3-DipoIare Cycloaddition von Dinitronen - Bildung tricyclischer Dimerer / 1,3 -Dipolar Cycloaddition of Dinitrones - Formation of Tricyclic Dimers
Authors: Aurich Hans Günter , Chair Abdellatif 
Published: February 2015

Abstract Various dialdehydes (1 -5) were formed by addition of dithiols to acrolein. Reaction of these dialdehydes with N-alkylhydroxylamines afforded dinitrones the two nitrone groups of which were joined by an alkylidene chain containing two sulfur atoms (6a,b-10a,b). Cycloaddition of these dinitrones with dimethyl acetylenedicarboxylate proceeded in the usual way giving bis(4-isoxazolines) (11a-15a).
However, analogous dinitrones formed by reaction of the dialdehydes with N-(4-tert-butylphenyl)
hydroxylamine could not be isolated. Instead tricyclic compounds arose in which
the central macrocyclic ring is flanked by two isoxazolidine rings (16c-20c). Obviously, the
dinitrones formed as intermediates underwent dimerization with formation of the tricyclic
compounds by cycloaddition between two nitrone groups and two tautomeric N-hydroxyenamine
moieties.
Two of the tricyclic compounds (16c and 20c) formed 1:1 complexes with NiCl2 and FeCl3,
respectively.
RbTe6, ein Polytellurid mit Schichtstruktur 2
∞[Te6
-] / RbTe6, a Polytelluride with Layer Structure 2
∞[Te6
-]
Authors: Sheldrick W. S. , Schaaf B. 
Published: February 2015

Abstract
Reaction of Rb2CO3 with Te in Methanol at 160 °C in the presence of Ge yields the polytellu­ ride RbTe6, the structure of which has been deter­mined by X-ray structural analysis. The poly­anions 2
∞[Te6
-] contain Te6 rings with a chair conformation, which are connected via four Te-Te bonds into a layer structure. A T structure is exhibited by the resulting TeTe3 units. The Rb cations adopt positions between neighbouring parallel anion layers and are surrounded by 12 Te atoms in their first coordination sphere.
Der zweikernige Fe(III)-Komplex von N,N,N',N'-Tetrakis(2-pyridylmethyl)-2-hydroxy-1,3-diaminopropan - Molekül- und Kristallstruktur und seine Wechselwirkung mit Montmorillonit / The Binuclear Fe(III) Complex of N,N,N',N'-Tetrakis(2-pyridylmethyl)-2-hydroxy-1,3-diaminopropane - Molecular and Crystal Structure and its Interaction with Montmorillonite
Authors: Weiss Armin , Dick Stefan 
Published: February 2015

Yellow crystals of [Fe2(HPTP)(OH)(NO3)2](Cl04)2 (HPTP = N,N,N',N'-tetrakis(2-pyridyl- methyl)-2-hydroxy-1,3-diaminopropane) were grown by slow diffusion of diethylether into a solution of the complex salt in acetonitrile. Crystal data: space group R3̅, a = 4280,1(15) pm, c = 1147,6(7) pm, Z = 18. The complex exhibits a binuclear Fe(III) core with (μ-oxo)(μ-alkoxo) ligands as bridging units. The nitrate anions coordinate each with a short and a long Fe-O bond. The coordination spheres of the iron atoms can be looked at as distorted edge-shearing pentagonal bipyramides.
The complex cation was introduced into the interlayer region of montmorillonite by cation exchange in acetonitrile. The results of X-ray, IR- and UV/VIS experiments suggest that the cation exchange is reversible. In the interlayer region the dinuclear cations are arranged in a rather loosely packed way, thus creating channels similar to those in pillared smectites or zeolites, respectively.
Structural Characterization of Dihydroselenapyrans Prepared by the Reaction of Diarylselenoketones with Conjugated Dienes
Authors: Fröhlich Roland , Grehl Matthias , Wilker Stefanie , Erker Gerhard , Mazerolles Pierre , Laurent Christian 
Published: February 2015

Abstract
Diarylselenoketones Ar1Ar2C=Se (2b: Ar1 = C6H5, Ar2 = -p-C6H4Cl; 2c: Ar1 = Ar2 = -p-C6H4F) were generated by treatment of the corresponding ylides with elemental selenium (“Staudinger-Chalcogenation”) and trapped with 2,3-dimethylbutadiene and 3,4-bis(methylene)-1,1-diphenyl-1-germacyclopentane, respectively, to yield the substituted 2,2-diaryl-3,6-dihydro-2H-selenapyrans 5b and 5c. The compounds 5b and 5c were characterized by X-ray crystal structure analyses.
Ho4C7, Y4C7: Carbide mit C3
4-- und C4- -Ionen / Ho4C7, Y4C7: Carbides with C3
4- and C4- Ions
Authors: Mattausch Hansjürgen , Gulden Thomas , Kremer Reinhard K. , Horakh Jörg , Simon Arndt 
Published: February 2015

Abstract
The new compounds Ho4C7 and Y4C7 have been prepared by reaction of stoichiometric amounts of the metals and C in closed Ta capsules at 1450 and 1300 K. respectively. With HoF3 as a flux, black, needle like single crystals of Ho4C7 were obtained, which are air and moisture sensitive. Ho4C7 crystallizes in the space group P21/n (No. 14) with lattice constants a = 368.06(3), b = 1251.8(1). c = 1364.4(2) pm and β = 96.62(1)°. Y4C7 with a = 370.08(5), b = 1258.9(1), c = 1371.8(1) and β = 96.61(1)°.
Two different kinds of carbon species occur in the two structures: isolated C4- ions and C3
4- units, respectively. The C4- ions are octahedrally surrounded by Ho-atoms. The Ho6C octahedra are condensed to form double chains parallel [100]. The chains are linked via C3
4- ions, which occupy positions above the edges of the Ho octahedra. Additional Ho atoms are located in voids between the C3
4- units.
The compounds are electrically semiconducting. Ho4C7 has a magnetic Curie-Weiss behaviour with θ= -28(4) K and µeff= 8.8(2) µB.
Zur Struktur von Dihydroxonium Alkandisulfonaten / The Structure of Dihydroxonium Alkanedisulfonates
Authors: Sartori Peter , Jüschke Ralf , Boese Roland , Bläser Dieter 
Published: February 2015

Abstract
The crystal structures of methanedisulfonic acid-(1) and 1,2-ethandisulfonic acid-dihydrate (2) have been determined from single crystal X-ray diffraction at T = 145 K (for 1) and T = 125 K (for 2). It has been found, that both acids exist in an ionic form as dihydroxonium sulfonates, but differ in the geometry of the sulfonate groups and in the positions of the hydrogen atoms at the oxonium ions.
Calorimetrie an Yttriumtrihalogeniden und Yttriumoxidhalogemden / Calorimetry of Yttrium Trihalides and Yttrium Oxyhalides
Authors: Oppermann H. , Ehrlich S. , Hennig C. 
Published: February 2015

Abstract
The heats of solution of Yttrium, YOCL, YOBr, YOI, YCl3, YBr3, YI3 and Y2O3 were determined in 4n HX. From those the enthalpies of formation of Yttrium Trihalides YX3 and Yttrium Oxyhalides YOX at 298 K were derived:
ΔHB
0(YCl3,f,298) = -240.4 ± 0.6 kcal/mol, ΔHB
0(YBr3,f,298) = -202.1 ± 1.5 kcal/mol,
ΔHB
0(YI3,f ,298) = -147.0 ± 1.7 kcal/mol, ΔHB
0(YOClf,298) = -240.2 ± 1.0 kcal/mol,
ΔHB
0(YOBrf,298) = -229.7 ± 2.0 kcal/mol, ΔHB
0(YOIf ,298) = -208.8 ± 2.0 kcal/mol.
Synthese und Kristallstruktur von Pentakis(dimethylsulfoxid)- oxo-titan(IV)chlorid / Synthesis and Crystal Structure of Pentakis(dimethylsulfoxide)-oxo-titanium(IV) Chloride
Authors: Enders M. , Rudolph R. , Pritzkow H. 
Published: February 2015

Abstract
Pentakis(dimethylsulfoxide)-oxo-titanium(IV) chloride is obtained by reaction of titanium tetrachloride with a stoichiometric amount of water in dimethylsulfoxide. A single crystal structure determination (P1̄, a = 9.564(6), b = 10.504(7), c = 12.510(8) Å, α = 70.21(5), β = 83.48(5), γ = 89.82(5)°, V = 1174 Å3, Z = 2) shows a dicationic titanium(IV) complex with five dimethylsulfoxide ligands and one oxygen atom. The two chlorine anions are not bonded to the complex cation. The TiO6-fragment is a distorted octahedron, where five of the six oxygen atoms belong to the coordinated dimethylsulfoxide molecules.
Thermochemische Untersuchungen am System Bi/Se/O III. Zum quasibinären System Bi2O3 –Bi2Se3 und zum ternären Bereich Bi2O3– Bi2O2Se – Se – SeO2/Thermochemical Investigations on the System Bi/Se/O III.The Quasy Binary System Bi2O3-Bi2Se3and the Ternary Range Bi2O3-Bi2O2Se–Se–SeO2
Authors: Oppermann H. , Göbel H. , Schmidt P. , Schadow H. , Vassilev V. 
Published: February 2015

Only the ternary phase Bi2O2Se is shown to exists in the thermodynamical equilibrium in the investigated ternary system on the binary line Bi2O3-Bi2Se3. Its thermal decomposition was measured in a quartz membrane zero manometer. The enthalpy of formation and the standard entropy were derived from the temperature function of the decomposition equilibrium:
⊿H°f(Bi2O2Ses,298) = -104,6 ±4,0 kcal/mol
S°(Bi2O2Ses,298) = 43 ± 3 cal/K·mol.
The coexistence ranges in the ternary region Bi2O3- SeO2- Bi2O2Se-Se were followed by X-ray diffraction, IR spectroscopy and total pressure measurements of binary and ternary compositions.
1.2-Verzweigte Carbosiloxan-Dendrimere mit Hauptgruppenelementund Übergangsmetall-modifizierten Oberflächen / 1.2-Branched Carbosiloxane-Dendrimers with Main-Group Element and Transition-Metal Modified Surfaces
Authors: Brüning Karin , Lühmann Bettina , Lang Heinrich 
Published: February 2015

The preparation of the first and second generation carbosiloxane dendrimers Si[OCH2- CH2CH2 SiMe(OCH2C=CH)2]4 (3) and Si{OCH2H2CH2SiMe[OCH2CH2CH2SiMe(OCH2 - C=CH)2]2}4 (5) by the reaction o f Si(OCH2CH2CH2SiMeCl2)4 (1) or Si[OCH2CH2CH2SiMe- (OCH2CH2CH2SiMeCl2)2]4 (4) with HOCH2C =CH (2) in the presence o f NEt3 is described. Dendrimers 3 and 5 contain propargyloxy units as terminal groups, which can be transferred to Co2((CO)8 (6) to give the hexacarbonyldicobalt functionalized dendritic molecules Si{OCH2CH2CH2[(η-OCH2C=CH)CO2(CO)6]2}4 (7) and Si{OCH2CH2CH2SiMe-(OCH2CH2CH2SiMe[(η-OCH2C=CH)CO2(CO)6]2)2}4 (8).
All compounds were characterized by elemental analyses, spectroscopic studies (IR,1H-, 13C{1H }-, 29Si{1H} NMR) as well as GPC investigations
Darstellung, 11B-, 13C-NMR- und Schwingungsspektren von Cs2[B6Cl5(p-C6H4(NI-I2))] sowie Kristallstruktur von (Ph4P)2[B6Cl5(p-C6H4(NH2))]·2CH3CN · 0,5 Et2O / Preparation, 11B, 13C NMR and Vibrational Spectra of Cs2[B6Cl5(p-C6H4(NH2))] and Crystal Structure of (Ph4P)2[B6Cl5(p-C6H4(NH2))]· 2CH3CN · 0.5 Et2O
Authors: Zander S. , Preetz W. 
Published: February 2015

Abstract
By reduction of [B6Cl5(p-C6H4 (NO2))]2- with hydrazine in the presence of Raney nickel in dichlorom ethane solution the amino derivative [B6Cl5(p-C6H4(NH2)]2-is formed. X -ray diffraction analysis has been performed on a single crystal of (Ph4P)2[B6Cl5(p-C6H4(NH2] ·2CH3CN-0,5Et2O(triclinic, space group P1̅, a = 12.870(6), b = 12.9406(5), c = 35,870(7) Å , a = 91,63(4), ß = 93,22(7), γ = 98,04(8)°, Z = 2). The 11B NMR spectrum is consistent with a monosubstituted B6 cluster. The IR and R am an spectra exhibit characteristic BB, CH , CC, and NH vibrations, respectively.
Crystallographic and Spectroscopic Evidence of O-Bonding in 3d-MetaI Dicyanomethanidonitrite Complexes
Authors: Hvastijová M. , Kohout J. , Buchler J. W. , Katzenmeier H. W. , Kožíšek J. , Didierjean C. 
Published: February 2015

Abstract
The coordination of the dicyanomethanidonitrite group through the nitroso oxygen atom in the tetrakis(pyridine) complexes [M{ONC(CN)2}2(py)4], M = Ni, Co, Cu, and in the bis(pyridine) complex [Cu{ONC(CN)2}2(py)2] was proved by X-ray crystallography of the Ni11 complex and re-evaluated infrared spectra. The Ni11 and Co11 complexes exhibit almost octahedral structures composed of four pyridine nitrogen atoms and two oxygen atoms of dicyanomethanidonitrite ions. Both copper(II) complexes display a considerable axial distortion of the pseudooctahedral arrangement. In the bis(pyridine) Cu11 complex the ONC(CN)2 groups are involved in the bridging function by use of the oxygen and nitrile nitrogen atoms.
Darstellung und Strukturelle Charakterisierung von cis-und trans- Dicyclohexyl-3,3′,4,4′-tetracarbonsäure-tetramethylestern / Preparation and Structural Characterization of cis- and trans-Tetramethyl Dicyclohexyl-3,3′,4,4′-tetracarboxylates
Authors: Shiotani Akinori 
Published: February 2015

Abstract
In the catalytic hydrogenation of tetramethyl biphenyl-3,3′,4,4′-tetracarboxylate, tetramethyl dicyclohexyl-3,3′,4,4′-tetracarboxylates were obtained, from which we have isolated cis isomers as crystals. The base-catalyzed isomerization afforded the trans isomers. The structure of the products isolated was determined by single-crystal x-ray diffraction, which clearly reveals the axial and equatorial positions of the methoxycarbonyl group. The structures in solution are supported by 1H and 13C NMR data, and also by two-dimensional COSY techniques.
Synthesis, Spectroscopic Characterization and Crystal and Molecular Structures of {Ph4P[(Se04 )(SnPh3 )(SnPh3X)]}n (X = Cl, Br)
Authors: Diop C. A. , Diop L. , Russo U. , Sánchez-Díaz A. , Castiñeiras A. 
Published: February 2015

Abstract
The reactions of bis[triphenyltin(IV)] selenate monohydrate [(Ph3Sn)2O4Se · H2O ] with tetraphenylphosphonium halides Ph4PX (X = Cl, Br) led to the formation of 1:1 complexes of formula {Ph4P[(SeO4)(SnPh3 (SnPh3X)]k [X = Br (I) or Cl (II)], which were characterized by infrared, Mössbauer and H, 13C and Sn 119Sn NMR techniques and by X-ray diffractometry. The complexes have polymeric structures in which the [SnPh3]+ units alternate with bridging [SeO4]2- units, each of which also bears an SnPh3X side chain. In both the [SnPh3]+ and the [SnPh3X] units the coordination polyhedron of the tin atom is a distorted trigonal bipyramid.
New Metal-Rich Compounds NblrSi, NblrGe, and TalrSi -Synthesis, Structure, and Magnetic Properties
Authors: Mishra Ratikanta , Pöttgen Rainer , Kotzyba Gunter 
Published: February 2015

Abstract
The metal-rich intermetallic compounds NblrSi, NblrGe, and TalrSi were synthesized by arc-melting of the elements and subsequent annealing in glassy carbon crucibles in a high-frequency furnace. The three compounds were investigated by X-ray diffraction on powders and single crystals: TiNiSi type, Pnma, a = 641.27(3), b = 379.48(2), c = 727.70(3) pm, wR2 = 0.0773, 430 F2 values for NblrSi, a = 645.48(3), b = 389.21(2), c = 741.11(4) pm, wR2 = 0.0981, 297 F2 values for NblrGe, and a = 638.11(3), b = 378.69(2), c = 726.78(3) pm, wR2 = 0.0887, 290 F2 values for TalrSi with 20 variables for each refinement. The iridium and silicon (germanium) atoms form a three-dimensional network of puckered Ir3Si3 and Ir3Ge3 hexagons in which the niobium (tantalum) atoms fill larger cages. Magnetic susceptibility measurements on NblrSi and TalrSi indicate Pauli paramagnetism with room temperature susceptibilities of 0.30(5)·10-9 and 0.97(5)·10-9 m3/mol, respectively.
Wechselwirkungen in Molekülkristallen, 175 [1, 2]. Kristallzüchtung und Strukturbestimmung von {Cäsium-tetraphenylimido- diphosphat}-Aggregaten mit unterschiedlicher lipophiler Umhüllung durch verschiedenartig Methyl-substituierte Phenylringe sowie relativistische DFT-Modellberechnungen zu Cäsium/Cäsium-Wechselwirkungen / Interaction in M olecular Crystals, 175 [1,2]. Crystal Growth and Structure Determination of {Cesium-tetraphenylimidodiphosphate} Aggregates with Differing Lipophilic Wrapping Due to Differently Methyl-Substituted Phenyl Rings, and Relativistic DFT-Model Calculations of Cesium/Cesium Interactions
Authors: Bock Hans , Heigel Erik , Havlas Zdenek 
Published: February 2015

Abstract
In alkali-tetraphenylimidodiphosphate ion aggregates, the size of the cation determines the curvature of the ligand and, therefore, whether hexameric ellipsoidal clusters or polymeric chains are formed. To further characterize the ligand spatial requirements, the phenyl rings have been methylsubstituted in 4-, 3/5-, 3/4- or 2,3-positions, their conformations structurally analyzed and correlated with the van der Waals substituent profiles. In addition, relativistic density functional theory potential curves have been calculated for the Cs⊕ ··· Cs⊕
interactions in simplified model systems.
Synthesis and Solid-Phase Application of a 9-Xanthenyl Handle
Authors: Somlai Csaba , Hegyes Péter , Fenyö Róbert , Tóth Gábor K. , Penke Botond , Voelter Wolfgang 
Published: February 2015

Abstract
The acid-labile 5-[(9-aminoxanthen-2-yl)oxy]valeric acid was prepared in a six-step route. The usefulness of the resulting handle was investigated with solid-phase peptide synthesis of cholecystokinin-8 sulfate and the phosphorylated fragment of the ζ-subunit of the T-cell receptor complex 138-144.
Ab initio Calculations and Qualitative Valence Bond Considerations for H2N-NO2 (Nitramide) and H2N-NO (Nitrosamine)
Authors: Geith Janna , Klapötke Thomas M. , Harcourt Richard D. , Wolynec Peter P. 
Published: February 2015

Abstract
The structures, energies and vibrational frequencies of H2N-NO2 and H2N-NO have been calculated at HF, MP2(FC), MP2(FULL) and CISD levels of theory using a polarized triple-zeta 6-311+G(d,p) basis augmented with a diffuse function. In addition, the structures and energies were also computed at the QCISD(T)/6-311+G(d,p) level of theory. The structure and bonding in H2N-NO2 and H2N-NO is discussed on the basis of a Natural Bond Orbital Analysis (NBO analysis) and in addition based on qualitative valence bond (VB) considerations.
Hexakis(dimethylaminoxy)disiloxane: Insertion of an Oxygen Atom into the Si-Si Bond of a Disilane by Dimethylaminoxy Lithium
Authors: Mitzel Norbert W. , Losehand Udo 
Published: February 2015

Abstract
The compound (Me2NO)3SiOSi(ONMe2)3 was prepared by the reaction of LiONMe2 with Si2Cl6, a reaction in which oxygen is inserted into the Si-Si bond. The crystal structure of (Me2NO)3SiOSi(ONMe2)3 was determined and shows the compound to have a linear siloxane core and SiON units with small valence angles at oxygen, caused by weak Si (-N interactions leading to partially hypercoordinate Si centres.
Synthesen, Kristallstrukturen und magnetische Eigenschaften von [Li(12-Krone-4)2][Li(12-Krone-4)(OH2)]2[Nb6Cl18], [Li(15-Krone-5)2(OH2)]3[Nb6Cl18] und [(18-Krone-6)2(O2H5)]3[Nb6Cl18] / Syntheses, Crystal Structures and Magnetic Behaviour of [Li(12-Krone-4)2][Li(12-Krone-4)(OH2)]2[Nb6Cl18], [Li(15-Krone-5)2(OH2)]3[Nb6Cl18] and [(18-Krone-6)2(O2H5)]3[Nb6Cl18]
Authors: Ströbele Markus , Meyer H.-Jtirgen 
Published: February 2015

The title compounds were prepared through reactions of Li2Nb6Cl16 with the corresponding crown ethers in acetone. All three compounds were obtained as dark brown crystals. Their structures were solved with the means of single-crystal X-ray diffraction.
[Li(12-crown-4)2][Li(12-crown-4)(OH2)]2[Nb6Cl18]: space group P21/n, Z =2, a = 1320.4(1), b = 1879.1(1), c = 1321.7(1) pm, ß = 92.515(6)°, R1 = 0.0297 (I>2σ(I)). The crystal structure contains Li+ sandwiched by two 12-crown-4-ethers plus Li+ coordinated by one 12-crown-4- ether and one water molecule.
[Li(15-crown-5)2(OH2)]3[Nb6Cl18]: space group R3̅, Z = 3, a = b = 2081.7(1), c = 1991.7(1) pm, R1 = 0.0395 (I > 2σ(I)). In the crystal structure Li+ and one water molecule are sandwiched by two 15-crown-5-ethers.
[(18-crown-6)2(O2H5)]3[Nb6Cl18]: space group P1̅, Z = 1 ,a = 1405.1(1), b = 1461.1(2), c = 1492.2(2) pm; α = 98.80(1)°, ß = 98.15(1)°, γ = 97.41(1)°, R1 = 0.0538 (I > 2σ(I)). H5O2
+ was found in the structure refinement sandwiched between two 18-crown-6-ethers.
All compounds reported contain [Nb6Cl18] clusters with Nb-Nb distances between 299 and 301 pm. The paramagnetic behaviour expected for [Nb6Cl18]3- in all three compounds was confirmed by magnetic measurements.
First record of Ninia atrata (Hallowell, 1845) (Squamata: Colubridae) from Sierra Nevada de Santa Marta, northern Colombia
Authors: Meza-Joya Fabio Leonardo 
Published: February 2015

The current work provides the first confirmed record of Ninia atrata in the northern foothills of the Sierra Nevada de Santa Marta, La Guajira department, Colombia. This record extends the Colombian known species’ distribution ca. 320 km NW from the northernmost record and represents the first observation of the species in the Caribbean Region of Colombia.