bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Spirocyclic Aminosilanes with Electron Withdrawing Substituents at Nitrogen
Authors: Wollenweber Markus , Keese Reinhart , Stoeckli-Evans Helen 
Published: February 2015

Abstract
The first synthesis of spirocyclic tetrasulfonamidosilanes is described. According to the X-Ray structure analysis of the most stable tetratosylamidosilane obtained the Silicon is bonded to four Nitrogen atoms in a spirocycle and surrounded by four Oxygen atoms which are located above the planes of the SiN4 tetrahedron.
Metallkomplexe mit biologisch wichtigen Liganden, XCVIII Cyclopalladierte Schiff-Basen von α-Aminosäure- und Peptidestern/Metal Complexes of Biologically Important Ligands, XCVIII Cyclopalladated Schiff Bases of α-Amino Acid and Peptide Esters
Authors: Böhm Andreas , Schreiner Bernhard , Steiner Norbert , Urban Reinhold , Sünkel Karlheinz , Polborn Kurt , Beck Wolfgang 
Published: February 2015

Abstract
The reactions of Schiff bases from benzophenone and α-amino acid and peptide esters with tetrachloropalladate afford the chloro bridged ortho palladated complexes 1-8 and 11-18. The chloro bridges are cleaved by P and N donors (PR3, pyridine, α-amino acid ester) to give the monomeric complexes 19-35. From 1, 2, 3 and bidendate ligands (dppe, α-amino carboxylates, cysteine methyl ester) the bis(chelates) 36-41, with N-diphenylmethylene glycylglycine ester the C,N,N chelates 46 and 47 are obtained.
The complexes 14, 23 and 47 were characterized by X-ray diffraction. Due to the two neighbouring five membered chelate rings in 47 a considerable distortion from the square planar coordination is observed.
Kristallstrukturen der iodierten closo-Hexaborate trans-(Ph4P)2[B6H4I2], mer-(Ph4P)2[B6H3I3] · 2 CH2Cl2, trans-(Ph4P)2[B6H2I4] · 2 CH3CN und (CH2Py2)[B6HI5]/Crystal Structures of the Iodized closo-Hexaborates trans-(Ph4P)2[B6H4I2], mer-(Ph4P)2[B6H3I3] · 2 CH2Cl2, trans-(Ph4P )2[B6H2I4] · 2 CH3CN and (CH2Py2)[B6HI5]
Authors: Sonnak D. , Preetz W. 
Published: February 2015

Abstract
X-ray structure determinations have been performed on single crystals of trans-(Ph4P)2-[B6H4I2] (1) (triclinic, space group P1̄, a = 9.9680(12), b = 10.9690(11), c = 11.0470(14) Å,α = 88.167(9), β = 80.466(12), γ = 68.839(11)°, Z = 1), mer-(Ph4P)2[B6H3I3] · 2 CH2Cl2 (2)(triclinic, space group P1̄, a = 11.8694(11), b = 15.1699(13), c = 17.051(2) Å, α = 75.118(9), β = 71.953(10), γ = 69.331(8)°, Z = 2), trans-(Ph4P )2[B6H2I4] · 2 CH3CN (3) (monoclinic, space group P21/n, a = 14.9665(10), b = 7.6783(10), c = 23.385(3) Å, β = 95.78(9)°, Z = 2), and (CH2Py2)[B6HI5] (4) (orthorhombic, space group Pnma, a = 13.660(2), b = 11.8711(13), c = 13.839(2) Å, Z = 4). The B6 octahedra are compressed in the direction of the B-I bonds, resulting in shortened diagonal B ··· B distances with average values of the groups I-B ··· B-I = 2.37 and I-B ··· B-H = 2.43 Å as compared with H-B ··· B-H = 2.49 Å.
The Promotive Properties of Alkali Metal Nitrate Melts for the Partial Oxidation of Methane to Methanol
Authors: Lee Bor-Jih , Kitsukawa Shigeo , Asakura Shukuji , Fukuda Kenzo 
Published: February 2015

Abstract
(Na, K)NO3 melts of various ratios were used as promoters for the partial oxidation of methane to methanol. Experiments were performed in a flow reactor system under atmo­spheric pressure and at various temperatures in the range of 525-600 °C. The influence of reaction temperature, melt composition, and reduced oxygen species on methane conversion and methanol selectivity were investigated systematically. The major reaction products were CH3OH, CO, CO2, and trace amounts of C2H6 and C2H4. A methane conversion of 1.8-12.4% and a methanol selectivity of 0.4-14.1% were obtained under these reaction condi­tions. Binary melts could achieve higher methanol selectivity than a single melt. The amounts of reduced oxygen species O2
- and O2
2-

were estimated from thermochemical data according to the ion equilibrium in molten nitrates. The promotive effect of nitrate melts was confirmed and the results indicate that superoxide O2
- plays an important role for methanol formation.
Untersuchungen an Polyhalogeniden, XXXIV Cäsium(18-Krone-6)dichloroiodat, [Cs(C12H24O6)]ICl2/Studies on Polyhalides, XXXIV Cesium (18 -crown -6 )dichloroiodate, [Cs(C12H24O6)]ICl2
Authors: El Essawi Mervat , Tebbe Karl-Friedrich 
Published: February 2015

Abstract
The new compound [Cs(18-crown-6)]ICl2 has been prepared by the reaction of cesium chloride and 18-crown-6 with iodine chloride in ethanol and structurally characterized by X-ray diffrac­tion methods. The geometries of the cation [Cs(18-crown-6)]+ and of the anion ICl2
- are as expected.
Isoselenocyanatoborate -Kristallstrukturen von (n-Bu4N)[BH(NCSe)3] und (Ph4P)[B3H7(NCSe)] / Isoselenocyanatoborates -Crystal Structures of (n-Bu4N)[BH(NCSe)3] and (Ph4P)[B3H7(NCSe)]
Authors: Steuer B. , Preetz W. 
Published: February 2015

Abstract
The treatment of [B6H6]2- with an excess of (SCN)2 in dichloromethane in the presence of solid KOH gives the hexaisoselenocyanatodiborate anion [B2(NCSe)6]2- as an intermediate (δ(11B) = -10.3 ppm), from which [BH(NCSe)3]- and elemental selenium are formed. The X-ray structure determinations on single crystals of (n-Bu4N)2[BH(NCSe)3] (1) (triclinic, space group Pi with a = 8.512(2), b = 10.885(3), c = 14.895(4) Å, α = 79.52(2), β = 74.86(2), γ = 86.768(2)°, Z = 2) and (Ph4P)[B3H7(NCSe)] (2) (monoclinic, space group C2, a = 7.686(5), b = 10.366(3), c = 17.533(3) A, β = 108.89°, Z = 4) show that the selenocyanate groups are coordinated exclusively via the N atoms with average bond lengths of B-N = 1.52, C-N = 1.15, C-Se = 1.75 A and angles N-C-Se = 179°, B-N-C = 168.7 - 176.8°. The N-B-N angles of 1 range from 107.5 to 109.5°.
Isolierte 1
∞[TeO5]-Oktaederketten im Bleitellurat Pb2TeO5 / Isolated 1
∞[TeO5] Chains of Octahedra in the Lead Tellurate Pb2TeO5
Authors: Wedel B. , Wulff L. , Müller-Buschbaum Hk. 
Published: February 2015

Abstract
Single crystals of Pb2TeO5 have been prepared by flux techniques. X-ray investigations showed a new crystal structure with monoclinic symmetry, space group C4
S -Cc, a = 13.099(3), b = 5.714(1), c = 7.520(2) Å, β = 123,80(3)°, Z = 4. Pb2TeO5 is characterized by 1
∞[TeO5] chains of octahedra isolated from each other and incorporated into an edge, corner and face connected frame of PbO7 polyhedra. Possible positions of the lone pair of electrons of Pb2+ are estimated by calculations of Coulomb terms of lattice energy.
Synthesis and Reactions with CO and C2H4 of Cobalt(I) Complexes Containing Trimethylphosphine and Chelating o-Diphenylphosphanyl- phenolate Ligands
Authors: Klein Hans-Friedrich , Brand Alexandra , Cordier Gerhard 
Published: February 2015

Abstract
In tetracoordinate cobalt(I) halide compounds CoX(Ph2P⌒O H)(PMe3)2 (X = CI, Br) o-phos-phanylphenols PhaP⌒OH are coordinated as phosphane ligands. In the presence of base chelat­ ing anions Ph2P⌒O- give rise to pentacoordinate com plexes Co(Ph2P⌒O)(PMe3)3. Molecular structures are presented for both types of compounds. The five-membered chelate ring in Co(Ph2P⌒O)(PMe3)3 is resistant to protonation, and ring-opening is not observed in the presence of CO or C2H4. Replacing one of the trimethylphosphanes by one of the π-acceptor ligands affords fluxional complex molecules which upon cooling attain definite ground-state geometries out of a multitude of possible isomers.
Bonding in an Unusual Nickel Carbide
Authors: Merschrod Erika E , Tanga S. Huang , Hoffmann Roald 
Published: February 2015

Abstract
The bonding in an unusual nickel carbide polymer network synthesized by Musanke and Jeitschko is analyzed using qualitative, band-structure calculations in the framework of extended Hiickel tight-binding theory. The carbide features infinite, one-dimensional, vertex-sharing chains of Ni squares. Each square is centered by a carbon and flanked by C2 units.
- In this electron-rich polymer, the Ni atoms act as electron acceptors through their s and p orbitals. The orbital interaction schemes reveal that there is little Ni-Ni bonding and essentially no Ni to C2 back-donation. Molecular orbital interaction diagrams of some molecular models are used to describe the bonding in 1
∞[Ni3Cs]8-.
We also discuss the stability of the planar building block of the polymer, (CNi4)4- (which resembles planar CH4) with respect to a “tetrahedral” alternative and we do so for the extended 1
∞[ Ni3C]4-and 1
∞[Ni3C5]8-chains. In each model case the tetrahedral alternative is favored, and there is no sign of stabilization of a crucial CL4 orbital. Such stabilization is partially achieved through bonding to two Ca axial to the C in the center of the Ni4 ring, but it takes the entire inter-chain calcium network to effect the observed stabilization.
Solventothermal Synthesis of the Lamellar Selenidostannates(IV) A2Sn4Se9 · H2O (A = Rb, Cs) and Cs2Sn2Se6
Authors: Loose Anja , Sheldrick William S. 
Published: February 2015

Abstract
Reaction of A2CO3 with Sn and Se in an H2O/CH3OH mixture at 115 - 130°C affords the isotypic lamellar selenidostannates A2Sn4Se9-H2O 1 (A = Rb) and 2 (A = Cs). The polyanions 2
∞[Sn4Se9
2-] exhibit Sn4Se5 es molecular building units, in which two adjacent Sn(IV) atoms of an Sn4Se4 8-membered ring are bridged by an additional Se atom. These units connect through (SnSe)2 4-membered rings to afford a 44 anionic net with 16-membered cavities. Cs2Sn2Se6 (3) may be prepared by methanolothermal reaction of Cs2CO3 with SnSe and Se at 130°C and contains porous 2
∞[SnTSe2- ] sheets in which 1
∞[SnSe3
2- ] ribbons are linked through Se-Se bonds. The resulting 44 net displays 14-membered pores in which the Cs cations reside.
Cyclodisilazane in cis-Konformation -eine einfache Synthese / Cyclodisilazanes in cis Conformation -a Facile Synthesis
Authors: Klingebiel Uwe , Tecklenburg Brigitte , Noltemeyer Mathias , Schmidt-Bäse Dieter , Herbst-Irmer Regine 
Published: February 2015

Abstract
Dilithium derivatives of bis(silylamino)fluorosilanes (1-3) react with chlorotrimethylsilane to give dilithium derivatives of the corresponding bis(silylamino)chlorosilanes and Me3SiF. LiCl-elimination in the presence of THF leads to the formation of silaamidides, which are isolated as dimers, four-membered cyclosilazane anions. (R′Si-NR)2Li(NR)2
㊀’, Li(THF)4㊉ (4, 6), and (THF)3Li-ClLi(THF)3
㊉ (5) cations. Hydrolysis of the dimeric silaamidides is the only but facile synthesis of cyclodisilazanes in cis-conformation (7 - 9). 1, 4, 7: R = Si(CMe3)2Me, R′= F; 2. 5. 8: R = SiMe2CMe3, R′= CMe3; 3, 6, 9: SiMe2CMe3, R = C6H5.
Reaction of 9-Borabicyclo[3.3.1]nonane with N-Trimethylsilylamines – Cleavage of the N–Si or N–H Bond
Authors: Wrackmeyer Bernd , Kehr Gerald , Alib Saqib 
Published: February 2015

Abstract
The reaction of dimeric 9-borabicyclo[3.3.1]no-nane 1 with N-trimethylsilyl-aniline 2 affords 9-anilino-9-borabicyclo[3.3.1]nonane 5 by elimina­tion of trimethylsilane. In contrast, 1 reacts with the N-trimethylsilyl-2-aminopyridines 3 and 4 se­ lectively by elimination of H2 to give the corre­sponding N-trimethylsilyl-aminoboranes 6 and 7. The latter reactions proceed via formation of bo-rane-pyridine adducts.
Koordinationsambidenz des Thiocyanations in Alkalitrithiocyanatomanganat(II)-Hydraten / Coordination Ambidence of the Thiocyanate Anion in Alkali Trithiocyanatomanganate(II) Hydrates
Authors: Biedermann Matthias , Hartung Helmut , Böhland Heinz , Matthäus Regina 
Published: February 2015

Abstract
Alkali metal trithiocyanatomanganate(II) hydrates have been prepared and characterized by several analytical methods. The structures of NH4[Mn(NCS)3(H2O)] (1a), K [Mn(NCS)3(H2O)] (1b) and Na[Mn(NCS)3] · 3 H2O (2) could be elucidated by X-ray analysis, 1a and 1b are isotypic and form a polymeric layer structure which is characterized by the ambident nature of the thiocyanate ligand and binding of the water molecule to the octahedrally coordinated Mn atom. In 2 the complex manganate(II) anions form a layer structure with trigonal symmetry in which each Mn atom is connected with three Mn neighbours by thiocyanate double bridges. The cation partial lattice consists of infinite chains of face-sharing [Na(H2O)6]+ octahedra running perpendicular to the anion layers.
Charge Transfer Interaction in (Riboflavin)tricarbonylrhenium(I) Chloride
Authors: Kunkely Horst , Vogler Amd 
Published: February 2015

Abstract
[Re(riboflavin)(CO)3Cl] shows intraligand (λmax = 476 and 518 nm) and Re(I) to π* (riboflavin) metal-to-ligand charge transfer, MLCT, (λmax = 556 nm, in CH3CN) absorptions in close proximity. The MLCT band undergoes a moderate solvent-dependent shift (negative solvatochromism) indicating a partial charge separation in the excited state. The complex is not photoluminescent.
Neue Synthesen mit Magnesiumhydrid. Teil 3: Herstellung nanokristalliner und amorpher Metalle durch Hydridreduktion / New Syntheses with Magnesium Hydride. Part 3: Preparation of Nanocrystalline or Amorphous Metals by Hydride Reduction
Authors: Knott Wilfried , Georg Frommeyer Georg , Klapdor Astrid , Windbiela Dagmar 
Published: February 2015

Abstract
The tribochemical reduction of metal halides by magnesium hydride in organic solvents allows the synthesis of nanosize or amorphous metals.
Gold(I)-Komplexe mit Aminliganden, II. (Methylpyridin)-Komplexe von Gold(I) Gold(I) / Complexes with Amine Ligands, II. Methylpyridine Complexes of Gold(I)
Authors: Jones Peter G. , Ahrens Birte 
Published: February 2015

Abstract
Gold(I) complexes of overall formula LAuCl (L = various methylpyridines) are non-conducting in acetone. X-ray structure analyses show that the solid state structure of the cor­ responding complex 1 (L = 2-picoline) is molecular; the 3-picoline derivative 2 is however ionic (L2Au)+(AuCl2)-. 3-Picoline forms a molecular complex LAuC6F5 (3) and also the ionic (L2Au)+(SbF6)- (4). Complexes 1, 2 and 4 display short Au ··· Au contacts, leading to chains of gold atoms; additionally, complexes 3 and 4 show weak Au ··· F contacts. The (3-picoline)-gold(III) complex trans-(L2AuCl2)+(SbF6)- (5) was obtained as a by-product; it too contains short Au ··· F contacts.
Ternary Intermetallic Compounds LnMn2Al10 (Ln = Y, La-Nd, Sm, Gd-Dy) and LnRe2Al10 (Ln = Ce, Pr, Sm) with CaCr2Al10-Type Structure
Authors: Thiede Verena M.T. , Jeitschko Wolfgang 
Published: February 2015

Abstract
The twelve title compounds have been prepared for the first time. Their CaCr2Al10-type structure (P4/nmm, Z = 4) was refined from single-crystal X-ray data for the three representatives TbMnAl10 (a = 1274.3(2) pm, c = 511.4(2) pm, R = 0.025 for 680 structure factors F and 43 variable parameters V), CeRe2Al10 (a = 1295.5(5) pm, c = 517.2(4) pm, R = 0.054 for 810 F and 46 V), and SmRe2Al10 (a = 1291.5(2) pm, c = 516.5(1) pm, R = 0.021 for 622 F and 46 V). The atomic positions of the lanthanoid and transition metal atoms are fully occupied. Significant deviations from the full occupancies were observed for two aluminum sites in TbMn2Al10 and for all five aluminum sites of the two rhenium-containing compounds, resulting in the compositions TbMn2Al9.63(2), CeRe2Al9.52(8), and SmRe2Al9.16(9). The cell volume of CeRe2Al10 and to a smaller extent also that of CeMn2Al10 indicate mixed or intermediate +III/+IV valencies of the cerium atoms in these compounds. The structural relationships between the three closely related body-centered tetragonal structures of ThMn12, CeMniAl8, DyFe6Al6 and the primitive tetragonal structure of CaCr2Al10 are briefly discussed.
Crystal Engineering towards Design of Macrocyclic Coordination Compounds: Crystal Structure of Rubidium Tetrachloro-and Tetracyanoaurate(III) Complexes with 18-Crown-6
Authors: Manskaya Julia A. , Domasevitch Konstantin V. , Ponomareva Vera V. , Sieler Joachim , Kokozay Volodimir N. 
Published: February 2015

Abstract
The new macrocyclic complexes of composition Rb(18-crown-6)AuX4 (X = Cl (1) and CN (2)) have been prepared and characterized by X-ray crystallography (1: monoclinic, space group P21/n, with a = 8.747(1), b = 8.366(1), c = 15.404(1) Å; β = 104.37(1)°, V = 1092.0(3) Å3 , Z = 2; final R1 =0.025 for 2030 independent reflections used; 2: monoclinic, space group P21/c, with a = 14.765(3), 6 = 17.134(3), c = 8.855(2) Å; β = 90.20(1)°, V = 2240.2(8) Å3, Z = 4; final R1 = 0.080 for 2034 independent reflections used). Both structures consist of Rb(18-crown-6)+ cations (A) and complex aurate(III) anions AuX4
- (B). Complex 1 has a linear polymeric array -A-B-A-B-(Rb-Cl 3.604(3), 3.654(3) Å) with the rubidium ions disordered 0.276(2) Å above and below the crown ether plane (Rb-O 2.819(5)-2.884(5) Å, av. 2.846(5) Å). The positioning of the rubidium atom away from the center of the 18-crown-6 is effected by the packing of the Rb(18-crown-6)+ and AuCl4
- moieties, and by the resemblance in the charge and symmetry of the cationic and anionic parts of the structure. Complex 2 has a zig-zag polymeric array -A-B-A-B-(Rb-N 2.92(2), 2.94(1) Å) with orthogonal disposition of Rb(18-crown-6)+ and Au(CN)4
- planes. The rubidium atom is situated 0.90(2) Å above the mean plane of the macrocyclic oxygen atoms (Rb-O 2.93(5)-3.15(4) Å) and adopts a typical “sunrise coordination”.
Strukturuntersuchungen an Dihalogen(diphosphan)nickel-KompIexen in Lösung mit Differential-Puls-Polarographie / Structure Analysis of Dihalogeno(diphosphine)nickel Complexes in Solution with Differential Puls Polarography
Authors: Mutz Martin , Latscha Hans Peter 
Published: February 2015

Abstract
The structures of twelve dihalogeno(diphosphine)nickel complexes of the general formula [NiX2(PR′2R′)2] (X = Cl, Br and I; R′ resp. R″ = -C2H5 or -C6H5) were analyzed in solution by differential puls polarography and 1H-NMR spectroscopy as a function of temperature.
Festphasensynthese von Muramyldipeptiden an isomeren Trialkoxybenzylamin-Harzen / Solid Phase Synthesis of Muramyl Dipeptides on Isomeric Trialkoxybenzylamine Resins
Authors: Kohlbaua Hans-Jürgen , Tschakert Jochen , Al-Qawasmeh Raed A. , Nizamì Tanveer Ahmad , Malik Abdul , Voelter Wolfgang 
Published: February 2015

Abstract
New isomeric trialkoxybenzylamine resins are developed coupling phthalimidomethyl-3,5-dimethoxyphenols to the Merrifield resin, followed by subsequent treatment with hydrazine. The generated benzylamine function allows DCC coupling w ith the carboxyl function of amino acids and peptides which are removed as amides after treatment with trifluoroacetic acid. These new trialkoxybenzylamine resins allow expeditious syntheses of peptide amides and glycopeptide amides as is demonstrated for muramyl peptides and analogues.
Variations in the Chain Structure of Cationic (Phosphine)gold(I) Dialkyldithiophosphate Complexes
Authors: Preisenberger Max , Schier Annette , Schmidbaur Hubert 
Published: February 2015

Abstract
Treatment of dithiophosphoric acid diesters (RO)2P(S)SH with appropriate quantities of tris[(phosphine)gold(I)]oxoniumtetrafluoroborates {[(R′3P)Au]30}+ BF4- in dichloromethane gives di-or trinuclear complexes of the types {(RO)2P[SAu(PR3)]2/3}+/2+ (2) BF4- as colour­ less, crystalline salts. As determined by single crystal X-ray diffraction studies, in the 1:2 complexes (with R = R′ = Me and R′ = Et, R = Ph and o-Tol), each gold atom is attached to a different sulfur atom, but with short intracationic Au-Au contacts. These cations are associated to form strings through intermolecular Au-Au contacts in the first case (R = Et), but through additional Au-S contacts in the second (R = Ph). For R = o-Tol, the cations are not associated at all owing to steric hindrance. This result is indicative of very small energy differences between the two modes of association. The 1:3 complexes are fluxional in solution and show virtually equivalent R3PAU groups in the NMR spectra at 20°C, but at low temperature non-equivalent ligands can be distinguished as shown previously for analogous dithiophosphinate derivatives.
Wechselwirkungen in Molekülkristallen, 143. ortho-Benzol-Derivate mit ineinander verzahnten Chlormethyl-und Methylamino-Substituenten: Strukturen und Rotationsenthalpie-Hyperflächen/ Interactions in M olecular Crystals, 143. ortho-Benzene Derivatives with M eshed Cogwheel Chlorom ethyl and Methylamino Substituents: Structures and Rotation Enthalpy Hypersurfaces
Authors: Bock Hans , Nagel Norbert 
Published: February 2015

Abstract
Facets of molecular dynamics in organic compounds such as coupled rotations of adjacent substituents are advantageously discussed based on structural data. Within this context, crystal structures of spatially overcrowded ortho-disubstituted benzene derivatives with chloromethyl or methylamino groups are presented together with semiempirical enthalpy hypersurfaces for the substituent rotation. Both compounds, 1 -trichloromethyl-2-dichloromethyl-benzene as well as l-trimethylammonium-2-dimethylamino-benzene exhibit comparable steric overcrowding and their preferred dynamics are predicted to be dominated by the rotation of the threefold substituted group during an approximate standstill of the twofold substituted, mirror-symmetric one. According to known solid state NMR measurements as well as to atom/atom-potential model calculations for the pentachloro ortho-xylene derivative, this molecular dynamic mode is still active in the crystal.
Darstellung, spektroskopische Charakterisierung und Kristallstruktur von Dicyclopentadienylcobalt-hexahydro-closo-hexaborat [(C5H5)Co(C5H4)B6H5Hfac]/ Synthesis, Spectroscopic Characterization and Crystal Structure of Dicyclopentadienyl- cobalt-hexahydro-closo-hexaborate [(C5H5)Co(C5H4)B6H5Hfac]
Authors: Schaper T. , Preetz W. 
Published: February 2015

Abstract
By reaction of [B6H6Hfac]- with cobaltocene in acetonitrile [(C5H5)Co(C5H4)B6H5Hfac] is formed. Its crystal structure has been determined by single crystal X-ray diffraction analysis (monoclinic, space group P21/n with a = 9.786(2), b = 9.726(2), c = 13.938(2) A, β = 107.2850(3)°, Z = 4). The B6 octahedron is slightly compressedoin the direction of the B-C bond by about 1%, with B-B bond lengths between 1.69 and 1.87 A. The 11B NMR spectrum exhibits a 1:4:1 pattern of a monosubstituted B6 cage. In the IR and Raman spectra characteristic B-H vibrations are observed.
A New Synthesis of Tetrakis(C-methyl)octakis(hydroxyethyl)calix[4]- resorcinarene via an Ethoxy-Tethered Trimethylsiloxy Precursor
Authors: Neda Ion , Siedentop Tjark , Vollbrecht Alexander , Thönnessen Holger , Jones Peter G. , Schmutzler Reinhard 
Published: February 2015

Abstract
The octakis(trimethylsiloxy)calix[4]resorcinarenes, 3 and 4, were synthesized by reaction of 1 and its tetrabromo derivative 2 with hexamethyldisilazane, and were found to exhibit dynamic behaviour in solution. Temperature-dependent NMR investigations confirmed the presence of at least two conformational isomers of 3 in solution. The conformation of 3 in the solid state was determined by an X-ray crystal structure analysis; the calixarene displays a boat conformation.
The introduction of the ethoxy group as a spacer into the molecule of 1 was effected via its reaction with ethyl bromoacetate and subsequent reduction with lithium aluminium hydride forming the ethoxy-tethered C-methylcalix[4]resorcinarene 6 in an impure state. Reaction of crude 6 with hexamethyldisilazane furnished the ethoxy-tethered octakis( trimethylsiloxy)calix[4]resorcinarene 7; its hydrolysis led to pure 6.
Kohlensäurebis(trimethylsilyl)ester: Spektroskopische Charakterisierung und verbesserte Darstellung/ The Bis(trimethylsilyl)ester of Carbonic Acid: Spectroscopic Characterization and Improved Preparation
Authors: Minkwitz Rolf , Schneider Stefan 
Published: February 2015

Keywords
The low temperature preparation of the bistrimethylsilylester of carbonic acid is reported. The hydrolysable and thermolabile (Me3SiO)2CO has been characterized by vibrational and NMR spectroscopic methods. Under inert conditions the (Me3SiO)2CO is stable at 233 K for several weeks.