bluuebunny/crossref_metadata_2025 huggingface dataset:
Elementorganische Verbindungen mit o-Phenylenresten, XV [1]. Hexamethoxy-tetrachalcogena-tetrahydropentacene / Organometallic Compounds with o-Phenylene Substituents, Part XV [1]. Hexamethoxy-tetrachaleogena-tetrahydropentacenes
Authors: Berges Peer , Klar Günter
Published: March 2015

The title compounds 4 and 5 were prepared by reaction of 1,4-dimethoxy-2,5-bis(3,4-dimethoxyphenylthio) benzene (8) with sulfur dichloride and selenium dioxide, resp., and characterized by 1H NMR and MS spectra. An X-ray analysis of 4 shows the compound to have a chair form, i.e. each of its two thianthrene units are folded at their SS axes in such a way that the two peripheral rings are found at different sites of the central ring plane (angles of fold 130.5°). The methoxy groups of the peripheral rings are coplanar, those of the central ring perpendicular to the corresponding ring planes. Bond distances and angles of 4 are in the normal range (CS 177.5 pm, CSC 100.2°).
The Electrochemical Synthesis of Neutral Zinc(II) Complexes of Schiff Base Ligands: The Crystal Structure of Bis[N-(4-methylphenyl)salicylaldiminato]zinc(II)
Authors: Sogo T. , Romero J. , Sousa A. , Blas A. de , Durán M. L. , Castellano E. E.
Published: March 2015

The electrochemical synthesis and physico-chemical properties of neutral zinc(II) complexes of bidentate Schiff bases derived from salicylaldehydes are presented together with the X-ray structure of bis[N-(4-methylphenyl)salicylaldiminato]zinc(II). The crystal is monoclinic, a = 21.877(3), b = 8.801(2), c = 12.027(5) Å, β = 96.55(3)°, space group C2/c. The complex is a monomer, and the zinc atom is tetrahedrally coordinated.
Synthese von 5-Alkyliden-2,3-pyrrolidindionen / Synthesis of 5-Alkylidene-2,3-pyrrolidinediones
Authors: Poschenrieder Hermann , Stachel Hans-Dietrich
Published: March 2015

The epoxyketone 3 is reduced by borohydride or a Wittig reagent to the oxiranes 6 or 9 respectively, which on acid hydrolysis yield 8a and 8b as derivatives of the title compound 1.
Allo-Verbindungen mit ungewöhnlichem Verhalten bei der Gaschromatographie an chiraler stationärer Phase / Allo-Compounds with Unusual Behaviour in Gas Chromatography Using Chiral Stationary Phase
Authors: Küsters Ernst , Rahmen Willy
Published: March 2015

The Separation of the enantiomers of D,L-allo-threoninol, necessary in racemization studies of peptide hydrolysates, gave a surprising result with respect to the elution series of the antipodes. Contrary to the rule (L before D on Chirasil-L-Val) D-allo-threoninol is eluted before its mirror image. This behaviour can only be explained by the differing importance of the asymmetric centres contained in the molecule. As a result of this and taking into account the chromatographic behaviour of allo-compounds refined model concepts of enantiomer separation must be devel-oped in future.

The separation of allo-compounds of threonine, isoleucine and cystathionine is considered from this aspect.
Evaluation of the 2 NH2A—T Pair in Hybridization, I Synthesis of the DNA/RNA Hybrid Oligomers Containing 2-Aminoadenosines
Authors: Kikuchi Kaeko , Taniyama Yoshio , Marumoto Ryuji
Published: March 2015

DNA decamers containing 2-aminoadenosine were synthesized. Oligonucleotide duplexes including the 2 NH2A-T base pairs were prepared and their Tm profile examined. Contrary to expectation, elevation of the Tm value by the 2 NH2 group is very small in DNA/RNA duplexes. From the CD spectra measurement, we assume that the distortion of the B-DNA structure caused by scattered DNA/RNA base pairing diminishes the efficient hydrogen bonding and base stacking of the duplexes. It was also found that the DNA duplexes containing 2-aminoadenosine hybrids are considerably resistant to ribonuclease T2 or nuclease P1 digestion.
Hydrierungen und Dehydrierungen im System Benzonitril/Ru3 (CO)12 /Benzylamin / Hydrogenations and Dehydrogenations in the System Benzonitrile/Ru3 (CO)12 /Benzylamine
Authors: Vahrenkamp Heinrich
Published: March 2015

The stepwise interconversions between benzonitrile and benzylamine have been realized in both directions via Ru3 cluster intermediates. The hydrogenation/dehydrogenation system can be entered from Ph-CN, Ru3(CO)12, and H2 yielding HRu3(CO)10(NCHPh) or from PhCH2NH2 and Ru3(CO)12 yielding HRu3(CO)10(NHCH2Ph), These two clusters can be interconverted by thermal hydrogenation and dehydrogenation, with H2Ru3(CO)9(NCH2Ph) as a CO and H2 depen­dent intermediate. The system can be left only towards benzylamine which is formed in small yields from HRu3(CO)10(NHCH2Ph) at high temperatures and under high CO or H2 pressures.
Metallorganische Lewis-Säuren, XXXV. Bildung und Struktur chalkogenverbrückter Metallkomplexe: [{(μ5-C5H5)(OC)2Fe}2SeSe{Fe(CO)2(μ5-C5H5)}]+BF4
- und [(μ5-C5H5)(OC)2FeS(R)Re(CO)5]+BF4
- (R = Me, Ph) / Organometallic Lewis Acids, XXXV. Formation and Stucture of Chalcogen Bridged Metal Complexes: [{(μ5-C5H5)(OC)2Fe}2SeSe{Fe(CO)2(μ5-C5H5)}]+BF4
- and [(μ5-C5H5)(OC)2FeS(R)Re(CO)5]+BF4
- (R = Me, Ph)
Authors: Fritz Peter M. , Beck Wolfgang , Nagel Ulrich , Polborn Kurt , Herrmann Wolfgang A. , Hecht Christian , Rohrmann Jürgen
Published: March 2015

The cationic diselenium bridged title compound 2 and [{(μ5-C5H5)(CO)2Fe}3Se]+BF4
- have been isolated from the reaction of (OC)5ReFBF3 with (μ2-Sen)[(μ5-C5H5)(CO)2Fe]2 (n = 1, 2). The heterometallic μ-thiolato title complex has been prepared from (OC)5ReFBF3 and (μ5-C5H5)(OC)2FeSR (R = Me. Ph; 4). The structures of 2 and 4a have been determined by X-ray diffraction analyses.
Borverbindungen, LXXXI. Neue Organobor-Sulfide — Herstellung und Anwendung / Boron Compounds, LXXXI. New Organoboron Sulfides — Preparation and Uses
Authors: Köster Roland , Seidel Günter
Published: March 2015

Bis(9-borabicyclo[3.3.1]nonane) reacts with sulfur to give the bis(1,5-cyclooctanediylboryl)- monosulfide (1) in high yield. The (9-BBN)2 disulfide 2 is easily prepared from 1 with sulfur. 2, which can also be obtained from 9-Iodo-9-BBN with sulfur, reacts with (9-BBN)2 to form 1.1 is an excellent sulfidation reagent for preparing thio compounds by S/O-exchange.
Zur Struktur der Kupfer-Weberite Na2CuCrF7 und Na2CuFeF7 / Concerning the Structures of the Copper Weberites Na2CuCrF7 and Na2CuFeF7
Authors: Kummer S. , Massa W. , Babel D.
Published: March 2015

The crystal structure of the compound Na-CuCrF7 (orthorhombic, a = 710.0, b = 1033.8, c = 751.8 pm, Z = 4) was refined in space group Pmnb to Rg= 0.028 (1545 independent reflections). The Jahn-Teller distortion of the CuF6 -octahedra (Cu-F = 191.1/193.8/212.4 pm. mean 199.1 pm) reduces the symmetry compared to the body-centered orthorhombic weberite type, to which it is otherwise closely related. The CrF6 -octahedra. interconnecting parallel chains of CuF6 -octahedra, are nearly undistorted (mean Cr-F = 190.6 pm). Na2CuFeF7 exhibits a supercell with a different structure (monoclinic, a = 2468.7, b = 734.7, c = 1245.2 pm, β = 99.29°, Z = 16). It may be interpreted as a new intermediate type between orthorhombic and trigonal weberites. Preliminary results obtained from refinement in space group A2/n (Rg = 0.076) are given and discussed (mean values Cu-F = 199 pm, Fe - F = 192 pm).
Ketenylidentriphenylphosphoran-Komplexe / Ketenylidenetriphenylphosphorane Complexes
Authors: Lindenberger Heide , Birk Reiner , Orama Olli , Huttner Gottfried , Berke Heinz
Published: March 2015

Ketenylidenetriphenylphosphorane complexes of the type LnMC(CO)PPh3 LnM = CpMn(CO)2 (2a), CpRe(CO)2 (2b) and Fe(CO)4 (3) are obtained by CO substitution reactions. The synthesis of 3 at 80 °C is accompanied by the formation of a Fe2(CO)6 compound with a bridging α-metallated formyl(triphenylphosphane)carbido ligand. From ethylation of 3 arises an Fe2(CO)6 ferrol-type complex 5.
Dichlorcyclopropenon als stabiler Komplexligand. Die Kristallstruktur von [NbOCl3·OC3Cl2]4 / Dichlorocyclopropenone as Stable Complex Ligand. The Crystal Structure of [NbOCl3·OC3Cl2]4
Authors: Patt-Siebel Ute , Thullen Helmut , Müller Ulrich , Dehnicke Kurt
Published: March 2015

The reaction of tetrachlorocyclopropene with NbOCl3 yields NbCl5·OC3Cl2 (1); 1 is also formed by partial hydrolysis of C3Cl3
+NbCl6
- (2), which is prepared from C3Cl4 and NbCl5. [NbOCl3·OC3Cl2]4 (3) was obtained by hydrolysis of 1 in form of pale-yellow, moisture sensitive, non-explosive crystals, and characterized by its IR spectrum and an X-ray crystal structure determination (1871 independent observed reflexions, R = 0.048). Crystal data: space group P1̄. Z = 2. a = 993.7(4), b = 1090.5(5). c = 1097.4(3) pm, α = 69.51(3), β = 70.47(3), γ = 66.51(4)° (at -17 °C). 3 consists of centrosymmetrical tetramers; the four Nb atoms form a square and are linked via almost linear oxo groups with alternating short and long NbO bonds with mean bond lengths of 175 and 208 pm. In trans position of each of the short NbO bonds a dichlorocyclopropenone molecule is attached via its oxygen atom with an NbO distance of 223 pm.
Darstellung und Kristallstruktur einiger Tetracarboxylatoaurate(III) / Preparation and Crystal Structure of Some Tetracarboxylatoaurates(III)
Authors: Jones Peter G. , Scheibach Ralf , Schwarzmann Einhard , Thöne Carsten , Vielmäder Andreas
Published: March 2015

Various salts M(AuX4)2 with X = OCOCH3 or OCOC2H5 have been prepared by two methods: (i) the reaction of metal hydroxides M(OH)2 with HAuCl4, followed by treatment of the intermediate products with acetic or propionic acid, or (ii) the reaction of aurates M{Au(OH)4}2 with the carboxylic acids. The crystal structure of Pb{Au(OCOCH3)4}2·2H2O shows that it is isostructural to the strontium salt, consisting of molecular units Pb{Au(OCOCH3)4}2 with crystallographic symmetry 2. The water of crystallization forms neither coordinate bonds to a metal nor hydrogen bonds. In the analogous zinc salt the water is coordinated to the zinc atom, and the structure is a layer polymer. The two compounds that crystallize in anhydrous form. Ba{Au(OCOCH3)4}2 and Pb{Au(OCOC2H5)4}2, have not yet yielded crystals suitable for X-ray analysis.
Fe4S4l2(SPPh3)2: ein neutraler, gemischt substituierter Eisen-Schwefel-Cluster / Fe4S4I2(SPPh3)2: a Neutral, Mixed Terminal Ligand Iron-Sulfur Cluster
Authors: Saak Wolfgang , Pohl Siegfried
Published: March 2015

Fe4S4I2(SPPh3)2 (1) was prepared by the reaction of Fe(THF)6Fe4S4I4 (THF = C4H8O). SPPh,. and sulfur in toluene and CH2Cl2. 1 has a lower stability than Fe4S4I4
2- and decomposes in solvents like THF and CH3CN. The crystal structure of 1 was determined from single crystal X-ray diffraction data. The compound crystallizes in the triclinic space group P1̄ with a = 1025.5(1). b = 1082.4(1), c = 2135.5(3) pm. α = 89.82(1), β - 77.37(1), γ = 73.56(1)°, V = 2214.1×106 pm3 and Z = 2. The [Fe4S4]2+ core of 1 exhibits a slight tetragonal distortion. The mean Fe-S and Fe-Fe distances were found to be 227.6 (225.8-228.7) pm and 273.3 (272.9-274.4) pm, respectively. The Fe-SPPh3 distances (231.6 and 232.1 pm) are longer than the terminal Fe-S bonds in RS coordinated [Fe4S4] clusters. The Fe-I bonds are found at 251.6 and 251.8 pm. respectively.
Synthese und Struktur von 1,3-Bis(4-trifluormethylphenyl)triazenido-Komplexen des Kupfer(I) und Silber(I) / Synthesis and Structure of 1,3-Bis(4-trifluormethylphenyl)triazenido Complexes of Copper(I) and Silver(I)
Authors: Hartmann Edmund , Strähle Joachim
Published: March 2015

[(F3CC6H4NNNC6H4CF3)Cu]4 (1) and [(F3CC6H4NNNC6H4CF3)Ag]n (2) are obtained by the addition of a solution of CuCl or AgNO, in CH3CN to a solution of Na(F3CC6H4NNNC6H4CF3) in THF. Recrystallization of 1 in toluene/n-hexane yields air-stable orange crystals (tetragonal space group P4̄21c, lattice constants a - 1527.7(5), c = 1281.3(4) pm, Z = 2). Complex 1 forms tetrameric units of symmetry S4 with the four Cu atoms forming a slightly folded rhombus. The triazenido ligands bridge the Cu atoms alternatingly above and below the rhombic Cu4 ring resulting in short Cu -Cu interactions of 257.9 pm. Complex 2 crystallizes from pyridine/methanol in form of yellow, air-stable crystals exhibiting a weak temperature independent paramagnetism of 0.64 B.M. per Ag atom at room temperature. The lattice constants are a = 2943(2), b = 475.8(5), c = 2280(1) pm. β = 111.99(6)°. Z = 8 for the monoclinic space group P21/c. The Ag atoms form zigzag chains with short Ag-Ag distances of 283.4 and 284.0 pm and angles Ag-Ag-Ag of 113.7 and 114.1°. The bridging triazenide ligands are arranged alternatingly above and below the Ag-Ag chain. Two symmetry independent zigzag chains are found in the unit cell.
Reactions of Substituted Vinyl Cations in Acetonitrile Solution as Studied by Flash Photolysis
Authors: Kobayashi Shinjiro , Zhu Qin Qin , Schnabel Wolfram
Published: March 2015

Vinyl cations I+, I+
b, I+
c of the structure R′2C=CR″ (I+
a: R′ = R″ = anisyl; I+
b R′ = phenyl.R″ = anisyl. I+
c: R′ - methyl.R″ = anisyl) were generated by flash photolysis of corresponding bromides. Lifetime measurements yielded the following: substitution of aromatic groups in 2-position by methyl groups largely improved the electrophilicity of the vinyl cations. The nucleophilicity of typical compounds (ketone, ester, alcohol, olefin) was measured.
Konformations- und Konfigurationsisomere substituierter 3-Oxa-7-azabicyclo[3.3.1]nonan-9-one / Conformational and Configurational Isomers of Substituted 3-Oxa-7-azabicyclo[3.3. l]nonan-9-ones
Authors: Ashauer-Holzgrabe Ulrike , Busch Thomas
Published: March 2015

The influence of the size of the substituents at N-7 is of great importance to the stereochemistry of 3-oxa-7-azabicyclo[3.3.1]nonanones. The conformational and configurational isomers I-III are isolated and MNDO calculations of these isomers are done.
N,N′-Bis(diphenyIphosphino)-S,S-dimethylsulfodiimin – ein Ligand für cyclische Übergangsmetallkomplexe/ N,N′-Bis(diphenylphosphino)-S,S-dimethylsulfodiimine – a Ligand for Cyclic Transition Metal Complexes
Authors: Roesky Herbert W. , Zimmer Michael , Herbst Regine , Sheldrick George M.
Published: March 2015

Me2SN2P2Ph4M(CO)4 complexes (1) (M: 1 a Cr, 1 b Mo, 1 c W) have been synthesized from Me2S(NPPh2)2 and C7H8M(CO)4 . 1a-1c are stable at room temperature, 1 b crystallizes in the space group P21212 with cell constants a = 2486.3(2); b = 1488.8(1); c = 882.0(1) pm.
Reaktionen der höheren Halogenide des Niobs, Molybdäns und Wolframs mit dem Phosphor-Ylid (Et2N)3P=CH2 - Röntgenstruktur von [(Et2N)3PCH2]2
2+[WCl6]2-/ Reactions of the Higher Halides of Niobium, Molybdenum and Tungsten with the Phosphorus-Ylid (Et2N)3P=CH2– X-Ray Structure of [(Et2N)3PCH2]2
2+[WCl6]2-
Authors: Roesky Herbert W. , Mainz Bernhard , Noltemeyer Mathias , Sheldrick George M.
Published: March 2015

(Et2N)3 P=CH2 reacts with NbCl5 , WCl6 or WF6 under C-C bond formation to give the phosphonium cation [(Et2N)3 PCH2]2
2+ · [(Et2N)3PCH2]2
2+ [WCl6 ]2 - was isolated in a crystalline form and investigated by X-ray analysis. The reaction of (Et2N)3 P=CH2 with MOCl4 in a solvent proceeds with formation of the [(Et2N)3 PCH ]+ cation.
Untersuchungen zur Ringkontraktion am 1,4-Dithia-2,6-diaza-3,5-diborinan-System/ Studies on Ring Contraction of the l,4-Dithia-2,6-diaza-3,5-diborinane System
Authors: Habben Carl , Meiler Anton , Pusch Stefan
Published: March 2015

The 1,4-dithia-2,6-diaza-3,5-diborinanes 1a-d react with elemental sodium with formation of the 1,3-diaza-2,4-diboretidines 2a-d. By use of more sodium in case of 1 d or 3,5-bis(diethylamino)- 2-cyclohexyl-6-trimethylsilyldiborinane, the 1,3-thiaza-2,4-diboretidines 3 were formed. 3.5-Dimethyl-2,6-bis(trimethylsilyl)-1,4-dithia-2,6-diaza-3,5-diborinane gives the borazine 4, The reaction of di-t-butyl-sulfurdiimide with 2,6-di-t-butyl-3,5-dimethyl-1,4-dithia-2,6-diaza-3,5-diborinane leads by ring contraction to the four-membered ring system 5. 1H, 11B, 13C NMR and mass spectra are reported and discussed.
Komplexe mit aromatischen Carbonsäuren, IV. Ca2[C6H2(COO)4]·6H2O - Eine neue Schichtstruktur/ Complexes with Aromatic Carboxylic Acids, IV. Ca2[C6H2(COO)4]·6H2O - A Novel Layer Structure
Authors: Robl Christian
Published: March 2015

Single crystals of Ca2[C6H2(COO)4]·6H2O were grown in aqueous silica gel. Ca2+ has CN 6+2. The coordination polyhedron is formed by three water molecules and five oxygen atoms of carboxylate groups. Six oxygen atoms are closely bound (235,9-243,9 pm), the two remaining coordination partners are considerably more remote from Ca2+ (268,2 and 273,8 pm). COO- groups chelate Ca2+ in an asymmetric manner, but the C -O bond lengths do not differ markedly (125,2-126,3 pm). The connection of Ca2+ with [C6H2(COO)4]4- leads to rigid layers. Adjacent layers are interlinked by hydrogen bonds. Those oxygen atoms which are weakly bound to Ca2+ are favoured as proton acceptors in hydrogen bonds. The COO groups are tilted differently against the C6-ring plane. One is approximately coplanar, but the other is oriented almost perpendicularly.
NaGaSn5, eine neue Zintl-Phase mit Ga–Sn-Schrauben/ NaGaSn5, a New Zintl Phase Containing Ga–Sn Helices
Authors: Blase Wolfgang , Cordier Gerhard
Published: March 2015

NaGaSn, (trigonal; P3112 (No. 151); a = 632.8(4), c = 617.0(3) pm, Z - 1; dx = 5.33 g/cm3) was grown from the melt. The crystal structure contains Ga and Sn atoms in a helical arrangement (six atoms per turn) along the c-axis direction. Interatomic bonding between neighbouring helices completes a distorted [2+2]-tetrahedral environment for every Ga/Sn position. The compound is classified in terms of the Zintl concept.
Synthese und Kristallstruktur von [Na-15-Krone-5][MoF5 (NCl)]
Authors: Fenske Dieter , Völp Karin , Dehnicke Kurt
Published: March 2015

[Na-15-Crown-5][MoF5(NCl)] has been prepared as yellow crystals by the reaction of NaF with MoF4(NCl) in the presence of 15-crown-5 in acetonitrile solution. The compound was charac­terized by its IR and 19F NMR spectra as well as by an X-ray structure determination. Crystal data: space group P21/n, Z = 4 (3736 observed, independent reflexions, R = 0.034). Lattice dimensions at -70 °C: a = 823.5(4). b = 1612.2(9), c = 1383.4(8), β = 99.35(3)°. The compound forms ion pairs, in which the sodium ion is seven-coordinated by the oxygen atoms of the crown ether molecule and by two fluorine ligands of the [MoF5(NCl)]- unit with Na-F distances of 228.3 and 249.6 pm. The Mo=N-Cl group of the anion is nearly linear (bond angle 175.8°) with bond lengths MoN = 172.9 and NCl = 161.8 pm.
Bioanorganische Modellkomplexe für Metalloproteine des Eisen(III) und Mangan(III): Synthese, Magnetismus und Kristallstrukturen von [L2Fe2(acac)2(μ-O)](ClO4)2, [L'Mn(acac)(OC2H5)]BPh4 und [L'Mn(acac)(OH2)](ClO4)2 (L = 1,4,7-Triazacyclononan, L' = N,N',N"-Trimethyl-1,4,7-triazacyclononan)
Authors: Wieghardt Karl , Pohl Klaus , Bossek Ursula , Nuber Bernhard , Weiss Johannes
Published: March 2015

The reaction of Fe(acac)3 (acac = acetylacetonate, 2,4-pentanedionate) with 1,4,7-triazacyclo- nonane (L) in acetone in the presence of water and NaClO4 yields green crystals of [L2Fe2
III(acac)2(μ-O)](ClO4)2 (1) a μ-oxo bridged dimer of Fe(III) the crystal structure of which has been determined. Hydrolysis of this material in an acetone/water mixture in the presence of NaBr yields the green tetramer [L4Fe4
III(μ-O)2(μ-OH)4]Br4 · 4H2O. Both compounds are strongly intramolecularly antiferromagnetically coupled. In contrast, the analogous reaction of Mn(acac)3 with L or N,N',N"-trimethyl-1,4,7-triazacyclononane (L') in ethanol or methanol yields yellow- green monomeric complexes of the type [LMnIII(acac)(OR)]+ or [L'Mn(acac)(OR)]+ (R = CH3, C2H5) which were isolated as tetraphenylborate or hexafluorophosphate salts. The crystal struc­ture of [L'Mn(acac)(OC2H5)]BPh4 (2) has been determined. If to the above reaction mixture cone. HClO4 was added, red [L'Mn(acac)(H2O)](CLO4)2 (3) precipitated. In alkaline aqueous solution [L'Mn(acac)(OH)]+ prevails. The crystal structure of 3 has also been determined. The new monomeric manganese(III) complexes have temperature independent (100-300 K) mag­netic moments of 4.8 to 5.1 μB in agreement with a high spin (d4) electronic configuration.
Darstellung und Struktur der zweikernigen tert-Butyliminovanadium(IV)-Komplexe: [(tC4H9N)2V2Cp2X2] (X = OtC4H9, Cl)
Authors: Preuss Fritz , Becker Harald , Kaub Jürgen , Sheldrick William S.
Published: March 2015

[(μ-NtC4H9)2V2Cp2(OtC4H9)2] (2) and [(μ-Cl)2V2Cp2(NtC4H9)2] (6) have been prepared by reac­tion of LitC4H9 with tC4H9N=VCp(OtC4H9)Cl and tC4H9N=VCpCl2, respectively. The molecular structure has been investigated by X-ray diffraction analysis. NMR and ESR Spectra indicate two types of tert-butyliminovanadium(IV) complexes: 2 (diamagnetic) and 6 (paramagnetic).
Anwendung der Mikhailovschen Allyloborierungssequenz auf Iminoborane
Authors: Paetzold Peter , Kiesgen Jutta , Plotho Christoph von , Schwan Heinrich
Published: March 2015

Iminoboranes RB≡NR' (1a,b; R/R' = iPr/iPr, Bu/tBu) have been allyloborated by triallylborane BAll3 (All = allyl). The resulting diborylamines All(R)B-N(R')-BAll2 undergo a thermal intra-molecular allyloboration to give azadiboracyclo-hexanes (3a, b).
Reductive Cleavage of Aryl-O-and Aryl-CI- Bonds by C8K: a Potential Method for the Degradation of Dioxins
Authors: Lissel Manfred , Kottmann Jürgen , Tamarkin Dov , Rabinovitz Mordechai
Published: March 2015

Potassium graphite intercalate in THF is a reagent for the reduction of aryl halides and the reductive cleavage of aryl ethers.
Antiprismatische und dodekaedrische Oktaaquokationen von Calcium und Strontium in den Kristallstrukturen von Tetrahalogenocadmaten und -mercuraten / Antiprismatic and Dodecahedral Oktaaquo Cations of Calcium and Strontium in the Crystal Structures of Tetrahalogeno Cadmates and Mercurates
Authors: Thiele Gerhard , Putzas Dietmar
Published: March 2015

The tetrahalogenometallates CaHgBr4·8H2O, CaCdI4·8H2O and SrCdI4·8H2O which have been obtained by crystallization from aqueous solutions form different structures. The orthorhombic compounds CaHgBr4·8H2O (Cmca, a = 1720.1(6) pm, b = 1329.2(4) pm. c = 1369.5(7) pm, Z = 8, R =0.041) and SrCdI4·8H2O (Pnma, a = 1404.6(2) pm, b = 1841.1(5) pm. c = 1420.6(3) pm, Z = 8, R = 0.037) are built up from dodecahedral [A(H2O)8 ] cations (A = Ca, Sr) and tetrahedral MX4 anions (M = Hg, Cd) which are cubic closed packed in a CuAu type structure. The tetragonal structure of CaCdI4·8H2O (P4/nbm, a = 1268.14(13) pm, c = 536.96(35) pm. Z = 2, R = 0.034) contains antiprismatic [Ca(H2O)8]2+ cations and tetrahedral Cdl4 anions, which form together a tetragonal primitive rod package.
Synthesen und Kristallstrukturen von [PPh3Me]NO2 und [PPh3 Me]HCO2H2O / Syntheses and Crystal Structures of [PPh3Me]NO2 and [PPh3Me]HCO2H2O
Authors: Essawi Mervat El , Gosmann H , Fenske D , Schmock F , Dehnicke K
Published: March 2015

Triphenylmethylphosphonium nitrite and formate have been prepared by the reaction of [PPh3Me]I with silver nitrite, and lead formate, respectively, in aqueous solutions. [PPh3Me]NO2 (1) forms pale yellow crystals, and [PPh3Me]HCO2·H2O (2) forms white crystals. Both compounds are soluble in water, ethanol, and dichloromethane. In moist air 2 is hydrated to yield [PPh3Me]HCO2·2H2O (3). The compounds were characterized by their IR spectra, 1 and 2 also by X-ray crystal structure determinations.

[PPh3Me]NO2 (1): space group P21/n, Z = 4, 2088 independent observed reflexions, R = 0.062. Lattice dimensions (20 °C): a = 914.7(3), b = 1887.5(9), c = 1080.0(4) pm, β = 110.29(3)°. The compound consists of PPh3Me+ ions and NO2- anions with bond lengths of 114.2(6) pm and a bond angle of 124.1(7)°.

[PPh3Me]HCO2·H2O (2): space group P21/n, Z = 4, 2973 independent observed reflexions, R = 0.069. Lattice dimensions (-20 °C): a = 931(2), b = 1558(3), c = 1281(2) pm, β = 105.9(1)°. The compound consists of PPh3Me+ ions and formate anions which form centrosymmetric dimeric units [HCO2·H2O]2
2- through hydrogen bridges of the water molecules. Bond lengths CO 122.4(4) and 120.9(4) pm. bond angle OCO 129.9(4)°.
Marine Natural Products, IX A New Halogenated Sesquiterpene Pinnatifidone from the Red Alga Laurencia pinnatifida
Authors: Bano Shaheen , Ali Mohammad Shaiq , Ahmad Viqar Uddin
Published: March 2015

From the ethyl acetate fraction of methanolic extract of red alga, L.pinnatifida, a new halogenated sesquiterpene named as pinnatifidone [1] has been isolated and the structure of this compound has been elucidated with the help of intensive spectroscopic studies.
Notizen: Fe(II) in Water: a Proposal for Dimerization
Authors: Meagher Adrian
Published: March 2015

The 57Fe Mössbauer quadrupole splittings of FeSiF6·6H2O (known to contain [Fe(H2O)6
2+) and fast frozen aqueous solutions of Fe(II) are different. We propose an explanation in terms of the dimerization of Fe(II) in aqueous solution via an H3O2-,H5O2
+ double bridge.
Metallkomplexe mit Tetrapyrrol-Liganden, LII [1]. Synthetische und elektrochemische Untersuchungen an Praseodym-bis(octaethylporphyrinat)-Systemen / Metal Complexes with Tetrapyrrole Ligands, LII [1]. Synthetic and Electrochemical Investigations on Praseodymium-bis(octaethylporphyrinate) Systems
Authors: Buchler Johann W. , Kihn-Botulinski Martina , Scharbert Bernd
Published: March 2015

The preparation of sandwich-type praseodymium-bis(octaethylporphyrinate) systems [Pr(OEP)2]n with different charges -1 ≤ n ≤+1 is described. The following derivatives have been isolated: Praseodymium(III)-hydrogen-bis(octaethylporphyrinate). PrH(OEP)2** (1; n = -1 ) . bis(octaethylporphyrinato)praseodymium(III), Pr(OEP)2 (2; n = 0). and bis(octaethylporphyrinato) praseodymium(III) diiodoaurate(I), [Pr(OEP)2][AuI2] (3; n = +1). For n = 0 or +1, one or both of the porphyrin π-electron systems have defect electrons. The compounds are identified by UV/VIS/NIR, IR and 1H NMR spectra. The cyclic voltammetry data of the "mixed valence' species Pr(OEP)2 in N.N-dimethylformamide are interpreted in terms of three reversible electron transfer processes. The behaviour of PrH(OEP)2 is complicated by a deprotonation occurring during the electrochemical experiment.
127I-Festkörper-NMR-Untersuchungen an (n–C4H9)4NIO4 und (n-C4H9)4PIO4 / 127I Solid-State NMR Investigations on (n-C4H9)4NIO4 and (n-C4H9)4PIO4
Authors: Burkert Paul K. , Grommelt M.
Published: March 2015

Tetrabutylammonium- and tetrabutyiphosphonium-metaperiodate show 127I solid-state NMR second order quadrupole splittings with quadrupole coupling constants in the range of 2-8 MHz. The values of e2qQ/h and asymmetry parameter n reveal several phase transitions of first and second order. In (n-C4H9)4PIO4 an anomalous temperature coefficient with ᾱ = 0.32 · 10-2 [K-1] is observed.
Organorheniumhalogenide: Synthesen, Strukturen und Reaktivität gegenüber Alkinen / Organorhenium Halogenides: Synthesis, Structure and Reactivity upon Treatment with Alkynes
Authors: Herrmann Wolfgang A. , Fischer Roland A. , Felixberger Josef K. , Paciello Rocco A. , Kiprof Pavlo , Herdtweck Eberhardt
Published: March 2015

The organorhenium(V) complexes (η5-C5Me5)ReX4 (2a, X = Cl; 2b, X = Br; Me = CH3) undergo stepwise dehalogenation upon treatment with various reducing agents, e.g. with HgCl2-activated aluminium powder, forming the isolable ReIV and ReIII dimers [η5-C5Me5)ReCl3]2 (3a) and [η5-C5Me5)ReX2]2 (4a, X = Cl;4b, X = Br), respectively. The weak metal-metal single bond of 3a (307.4(0) pm; X-ray diffraction study) is disrupted upon reaction with alkynes yielding the ReIII derivatives (η5-C5Me5)ReCl2(η2-R1CCR2) (9a-e; R1, R2: alkyl, aryl) and novel rhenium(V)- allylidenyl complexes of type (η5-C5Me5)ReCl2[η1:η3-R1CC(Cl)CHR3] (10a-d; R1: alkyl. aryl; R3: H, alkyl). Reduction of 2a (Al/HgCl2) in the presence of alkynes gives a complex reaction mixture of 9a-c, 10a - c and bis(π-alkyne) complexes [(η5-C5Me5)ReCl(η2-R1CCR2)2] + [AlCl4]-(11a-c) (X-ray diffraction study of the related derivative [(η5-C5Me5)ReBr(η2-MeCCMe)2] + [SbF6]-).
Selektive Metallierung von BicycIo[3.2.1]octa-2,6-dien, II Distannylierte Derivate und stannylierte tricyclische Sekundärprodukte / Selective Metalation of Bicyclo[3.2.1]octa-2,6-diene, II Distannylated Derivatives and Stannylated Tricyclic Secondary Products
Authors: Hertkorn N. , Köhler F. H.
Published: March 2015

Distannylated bicyclo[3.2.1]octa-2,6-diene (1) with (CH3)3 Sn groups in positions exo-4 and 7 (7a), endo-4 and 7 (7b), exo-4 and 6 (7c), and probably exo-4 and endo-4 (7d) are obtained when 1 is treated first with an excess of n-BuLi/t-BuOK in alkane and then with (CH3)3 SnCl. Byproducts are monostannylated derivatives of 1 and l,4-bis(trimethylstannyl)but-2-ene (3). The formation of 7a/b/c is best understood when the two possible bicyclo[3.2.1]octa-2,6-dienyl dianions are generated as intermediates. 3,exo-4-Bis(trimethylstannyl)bicyclo[3.2.1]octa-2,6-diene (7e) is ob-tained from the corresponding dibromo derivative of 1 and (CH3)3SnLi with 3-bromo-exo-4-trimethylstannylbicyclo[3.2.1]octa-2,6-diene (9) as an intermediate. The bicyclic stannyl com-pounds are susceptible to a 1,5-homopentadienyl shift of a (CH3)3Sn group at relatively low temperature when the starting compound has the stannyl group in position 4 of 1 and when positions 6 or 7 are unsubstituted. Tricyclo[3.2.1.02.7]oct-3-enes with (CH3)3Sn groups in positions exo-6 (5a), endo-6 (5b), 3 and exo-6 (10a), and 3 and endo-6 (10b) are thus obtained. On further heating, 10b gives l-trimethylstannyl-3-vinylbenzene (11). All compounds have been studied systematically by NMR spectroscopy including δ(119Sn), δ(13C), δ(1H), 4/5J(119/117Sn-119Sn), nJ(119/117Sn-13C) , nJ(119/117Sn-1H), 1J(13C-1H ) , and nJ(1H-1H ). Among all nuclei, 119Sn gives the most simple spectra. From the 13C NMR spectra a series of useful increments of (CH3)3Sn groups emerges. The most interesting coupling constants are 5J(119/117Sn-119Sn), for which a considerable change with the dihedral angle is established, and nJ(119/117Sn-13C). For n = 3 and 4 the latter are especially useful because their angular dependence leads to unambiguous signal assignments.
Funktionelle Trimethylphosphanderivate, XXVI [1]. Silylsubstituierte Phosphinomethane und Lithiumphosphinomethanide / Functional Trimethylphosphine Derivatives, XXVI [1] Silyl-substituted Phosphinomethanes and Lithiumphosphinomethanides
Authors: Karsch Hans H. , Appelt Armin , Deubelly Brigitte , Zellner Karin , Riede Jürgen , Müller Gerhard
Published: March 2015

The lithium phosphinomethanides LiCH(X)(PMe2) (X = H, PMe2 SiMe3) react with Me3SiCl to give silylsubstituted phosphinomethanes CH(X)(PMe2)(SiMe3). The latter are metalated by LiR (R = tBu, nBu). This metalation is facilated by the presence of Me2NCH2CH2NMe2 (TMEDA). X-ray structure determinations of {(TMEDA)Li[CH(PMe2)(SiMe3)]}2 (3b) and (TMEDA){Li[C(PMe2)(SiMe3)2]}2 (5b) show the marked influence of increasing silyl substitution on the structures of lithium phosphinomethanides: the Li-C contacts are weakened, whereas phosphorus forms additional (bridging) Li···P contacts to the second Li atom in the dimeric arrangements. In 3b, a six-membered ring in twist conformation is formed by head-to-tail dimerization. Likewise, 5b forms a six-membered ring, in this case by head-to-head dimerization. however, which may be regarded as a complex of a chelating phosphinomethyl lithiate ligand to [(TMEDA)Li]+ .
Beiträge zur Chemie des Bors, 195 [1]. Synthese, Struktur und Reaktionen eines 1,3,2,4-Aza-λ3-phosphadiboretidin-Derivats / Contributions to the Chemistry of Boron, 195 [1]. Synthesis, Structure and Reaction of a 1,3,2,4-Aza-λ3-phosphadiboretidine Derivative
Authors: Kölle Peter , Nöth Heinrich , Paine Robert T. , Rattay Wilfried
Published: March 2015

1,3-Di(tert-butyl)-2,4-di(2′,2′,6′,6′-tetramethylpiperidino)-1,3.2.4-azaphosphadiboretidine (6a), results from a diborylamine precursor by dehalogenation in good yield. The four-membered ring of this heterocycle is nonplanar and folded by 160° at the BB axis. The energy difference between this conformation and the planar ring is rather small.

CH3I and the W(CO)5-fragment add to the phosphorus atom of 6a. However, selenium achieves a break-down of the ring. One product obtained is the selenaazadiboretidin derivative (16).
Metallkomplexe mit biologisch wichtigen Liganden, XLVIII [1]. Palladium(II)- und Platin(II)-Komplexe mit α,β-Dehydro- und β-Chlor-α-aminosäurederivaten sowie mit O-Acetyl-L-serin / Metal Complexes with Biologically Important Ligands, XLVIII [1] Palladium(II)- and Platinum(II)-Complexes of α,β-Dehydro- and β-Chloro-α-amino Acid Derivatives and of O-Acetyl-L-serine
Authors: Steiner Norbert , Nagel Ulrich , Beck Wolfgang
Published: March 2015

The preparation and spectroscopic data of the complexes cis- and trans- CL2M(NH2C(CO2Et)=C<) , (1) (M - Pd. Pt), trans-Cl2Pd(NH2CH(CH2Cl)CO2CH3)2 (2), trans- Cl2Pd(NH2CH(CH2OAc)CO2)2 (3) and trans-Cl2Pt(Gly-β-Cl-AlaOMe)2 (4) are reported. The structures of l a and 2 have been determined by X-ray structure analysis. Elimination of hydrogen chloride from 4 gives the dehydrodipeptide complex 5.
σ-Ferrocenyl-Komplexe der frühen Übergangsmetalle – Synthese und Struktur / σ-Ferrocenyl Complexes of the Early Transition Metals – Synthesis and Structure
Authors: Wedler Michael , Roesky Herbert W. , Edelmann Frank T. , Behrens Ulrich
Published: March 2015

Ferrocenyllithium, FcLi (1), reacts with (C5H4CH3)2TiCl2, CpTiCl, and Cp*TiCl 3 to give the new σ-ferrocenyl complexes (C5H4CH3)2TiFc2 (2), CpTiFc3 (3) and Cp*Ti(Fc)2Cl (4), respectively. Treatment of Cp*2ZrCl2 with FcLi yields the mono-substitution product Cp*2Zr(Fc)Cl (5), which has been characterized by an X-ray structure analysis. Compound 5 crystallizes in the monoclinic space group P21/c (a = 1622.3(6), b = 995.0(2), c = 1664.3(6) pm; β = 94.78(3)°; Z = 4). Due to the sterically demanding pentamethylcyclopentadienyl ligands 5 contains a long zirconium-carbon bond (231.4(8) pm) and the Cp rings of the ferrocenyl substituent are tilted by 10.2°. The syntheses of CpZrFc3 (6), Cp*HfFc3 (7) and Cp2VFc2 (8) are also described.
Darstellung und Eigenschaften von Monofluoramin, H2NF / Preparation and Properties of Monofluoramine, H2NF
Authors: Minkwitz Rolf , Naß Rüdiger
Published: March 2015

Monofluoramine H2NF is prepared by thermolysis of H3NF+HF2--nHF and selective absorption of HF on activated KF. In the solid state H2NF is stable below 170 K, and immediately decomposes in NH4HF2
- and N2 by melting.
[1,4,2]Diazaphospholidine / [1,4,2]Diazaphospholidines
Authors: Fluck Ekkehard , Kuhm Peter , Riffel Heinz
Published: March 2015

Bis(diethylamino)phosphanylacetylen reacts with N.N′-dimethyl thiourea to give 2-diethyl-amino-1,4-dimethyl-3-methylene-[1,4,2]diazaphospholidine-5-thion (2) besides the [1,3,4]thiazaphospholidine (1). The latter compound is converted into 2 by heating. Reaction of 2 with various reagents yields other members of the title compound class. All new compounds are characterized by some reactions and their NMR and IR spectra. In addition, the results of an X-ray structure analysis of 2-diethylamino-l ,4-dimethyl-3-methylene-2-thioxo-[1,4,2]diazaphos-pholidine-5-thion (5) are reported.
Polysulfonylamine, XII [1]. N-Acyl-dimesylamine (N.N-Dimesyl-carbonsäureamide) / Polysulfonylamines, XII [1]. N-Acyl Dimesylamines (Carboxylic Acid N.N-Dimesylamides)
Authors: Blaschette Armand , Safari Firouz , Linoh Karin , Koch Dietrich
Published: March 2015

N-Acyl dimesylamines RC(O)N(SO2CH3)2 (3) have been prepared by reacting solid KN(SO2CH3)2 with neat liquid RC(O)Cl at 70-90 °C [R = C2H5, (CH3)2CH, (CH3)3C-CH2 , CH2Cl, CHCl2] or solutions of AgN(SO2CH3)2 in methyl cyanide with RC(O)Cl at room temperature [R = (CH3)3C, CH2Cl, CHCl2, CCl3 , C6H5 , CH2=CH]. Addition of chlorine or bromine to 3 (R = CH2 = CH) affords the corresponding compounds 3 with R = CH2Cl-CHCl and CH2Br-CHBr, respectively. By hydrolysis of 3 (R = CCl3), CCl3C(O)NHSO2CH3 (5) is obtained. The new compounds 3 and 5 are characterized by spectroscopic (NMR, MS) and analytical methods.
Intramolecular Thermal Rearrangement of Harmine Hydroiodide to a New Anhydronium Base, Methylharmol
Authors: Siddiqui Salimuzzaman , Sultana Naheed , Malik Abdul
Published: March 2015

Thermal rearrangement of harmine hydroiodide (1) at 300 °C provided a new anhydronium base provisionally named as methylharmol (3). The structure was assigned on the basis of UV, IR and NMR spectral data of the base and its tetrahydro product (2). Nitration of methylharmol afforded 12-nitromethylharmol (4).
Über die Reaktion einiger P(III)—OSiMe3-Verbindungen mit Hexafluoraceton / Reaction of Some P(III) —OSiMe3 Compounds with Hexafluoroacetone
Authors: Weferling Norbert , Schmutzler Reinhard
Published: March 2015

The P(III)trimethylsilylesters. RP(OSiMe3)2 (R = Me, Ph) and MeP(OBu")(OSiMe3). were synthesized by the silylation of the appropriate P(III)(:O)(H) compound with dimethylaminotrimethylsilane. Their reaction with hexafluoroacetone was studied with a view of synthesizing P-functional λ5P-trimethylsiloxy phosphoranes. From RP(OSiMe3)2 the expected bis(trimethylsilyl) perfluoropinacolyl phosphoranes, RP(OSiMe3)2(pfp = perfluoropinacolyl). were obtained. Their stability was limited, and transformation to the known λ4P species. RP(:O)(pfp), was observed. From the mixed P(III) ester, MeP(OBu")(OSiMe3). formation of a λ5P species was not observed, and the product was the same. MeP(:O)(pfp). A possible isomerization scheme for perfluoropinacolylbis(trimethylsiloxy)phosphoranes is discussed
Die Verfeinerung der Kristallstruktur von UTe2 / Refinement of the Crystal Structure of UTe2
Authors: Beck H. P. , Dausch W.
Published: March 2015

The crystal structure of UTe2 has been refined with single crystal data. The structure model proposed by Klein Haneveld and Jellinek on the basis of powder data could be verified (Sp. Gr. Immm, a = 415.9(1) pm, b = 612.4(2) pm, c = 1394.5(9) pm). Oxidation states are discussed on the basis of interatomic distances.
[M(II)([15]Krone-5)(L)2 ]++ -Komplexe -der Einfluß des Kronenetherhohlraums auf die Mobilität der Liganden L / [M(II)([15]Crown-5)(L)2]++ Complexes - The Influence of the Crown Ether Cavity on the Mobility of the Ligands L
Authors: Dickert Franz L. , Gmeiner Wolfgang , Feigl Matthias
Published: March 2015

The mobility of coordinated methanol in the complex [Co(II)(Benzo[15]crown-5)(CH3OH)2]f + was studied in nitromethane. The methanol exchange mechanism tends to an associative nature with an increasing amount of methanol in the solutions as can be deduced from the activation entropy. All activation data can be combined in an isokinetic relationship which is also valid for the respective complex with the unsubstituted [15]crown-5 ether ligand
Zur Kenntnis des Systems CsF/CuF2: Über Cs7Cu6F19 [1] / On the Knowledge of the System CsF/CuF2: On Cs7CuhF19 [1]
Authors: Kissel Dieter , Hoppe Rudolf
Published: March 2015

In the system CsF/CuF2 Cs7Cu6F19 was obtained as transparent pale blue single crystals [closed Au-tube; carefully dried Ar; 4 weaks 720 °C. 12 weaks 760 °C] and its structure was determined. The crystals are moisture sensitive.

The new fluorocuprate(II) crystallizes in the monoclinic system (P21/c) with a = 1173.1(1) pm; b = 626.56(6) pm; c = 1568.5(2) pm; β = 99.18° and Z = 2.

In the structure there are units of three face shared octahedra [Cu3F12] as in Cs4Cu3F10. These triples of octahedra are connected to "double-layers" a remarkable difference as compared to Cs4Cu3F10. The distances d(Cu-F) are ranging from 185.3 to 240.5 pm.

The Madelung Part of Lattice Energy, MAPLE, has been calculated and discussed and related to Effective Coordination Numbers, ECON, via Mean Fictive Ionic Radii. MEFIR
Cu2[Ph-C(NSiMe3)*]2, ein Amidinatokomplex mit kurzem Cu ··· Cu-Abstand / Cu2[Ph —C(NSiMe3)2]2, an Amidinato Complex with a Short Cu - Cu Distance
Authors: Maier Susanne , Hiller Wolfgang , Strähle Joachim
Published: March 2015

The copper(I)amidinato complex Cu2[Ph-C(NSiMe 3)2] ; has been prepared by the reaction of CuCl with N.N,N'-tris(trimethylsilyl)benzamidine in boiling acetonitrile. forming white crystals. The compound was characterized by its IR spectrum as well as by an X-ray structure determina-tion. Crystal data: space group P1̄, Z = 2 (2851 observed independent reflexions, R = 0.047). Lattice dimensions at 20 °C: a = 1135.0(3); b = 1219.6(4); c = 1372.4(4) pm; a = 106.74(3)°; β= 107.92(4)°; y = 91.40(4)°. The compound forms dimeric molecules with a short Cu···contact of 242 pm and two chelating amidinato ligands with Cu-N bond lengths of (averaged) 189.0 pm and bond angles N -C-N of 124.1°.
11B-NMR-Spektren von Alkyl-, Halogeno- und Rhodanohydrohexaboraten / 11B NMR Spectra of Alkyl-, Halogeno- and Rhodanohydrohexaborates
Authors: Heinrich A. , Preetz W. , Marsmann H. C.
Published: March 2015

The temperature dependence of the 11B NMR spectra of the monosubstituted and protonated c/oso-hexaborates RB6H6
-, R=CH3, C2H5, C3H7, C4H9 C8H17, (SCN)B6H6
- and XB6H6 X = Cl. Br. I, has been determined in the range 180-300 K. The extra proton migrates at higher temperatures intramolecularly, probably across the edges of the B6 core. The extra proton is fixed to a facet of the octahedron below the coalescence temperatures 240 K (RB6H6
-) and 210 K (XB6H6
-) as recognized by the splitting of the signal of the equatorial B atoms due to the lowering of the symmetry from C4v to Cs . From the spin-spin coupling it can be deduced that the proton prefers with the softer Brönsted acids RB6H6
- facets adjacent to the substituent, while with the stronger Brönsted acids XB6H6
- facets including the antipodal B atom are occupied.
On the Chemistry of Phorbol, XIX [1] Preparation of Tritium-Labelled 12-O-RetinoyIphorbol-13-acetate([20-3H]-RPA)
Authors: Tremp G. L. , Hecker E.
Published: March 2015

In contrast to established principles of radioactive labelling of diterpene esters such as TPA it was impossible to introduce tritium into the highly sensitive 12-0-retinoylphorbol-13-acetate (RPA) via reduction of its cold 20-aldehyde with [3H]-sodium borohydride. As an alternative successful procedure, [20-3H]-phorbol-13-acetate was prepared at first. It was protected in position 20 by reaction with tritylchloride and the tritylether reacted with retinoic acid. In both reactions appropriate phorbol acetates were used as easy to separate cold carriers. After removal of the 20-tritylether group, [20-3H]-RPA of a specific activity was obtained that was sufficient for the compound to be used as a tool in biochemical investigations
Molekül- und Kristallstruktur des l,l-Diethyl-3,5-dimethyl-1λ6,4,2,6,3,5- dithiadiazadiborins / Molecular and Crystal Structure of l,l-Diethyl-3,5-dimethyl-1λ6,4,2,6,3,5- dithiadiazadiborine
Authors: Habben Carl D. , Noltemeyer Mathias
Published: March 2015

The title compound, isolated from the reaction of SS-diethyl-N,N'-bistrimethylsilylsulfodiimide and 3.5-dimethyl-1,2,4-trithiadiborolane, crystallizes in space group Pbca with cell constants a - 1218.7(6), b = 1295.8(6), c = 1455.7(9) pm, V = 2.2987 m-3, Z = 8, ϱ = 1.167 Mg m-3. The X-ray structure was refined to R = 0.053
Phasendiagramme einiger Methylhalogensilane mit Pyridin und Lutidin Phase Diagrams of Methylhalogenosilanes with Pyridine and Lutidine
Authors: Hensen Karl , Dräbing Michael
Published: March 2015

By analyzing the phase diagrams of some trimethylhalogenosilane/pyridine- and methyl-trichlorosilane/lutidine-systems the existence of the incongruently melting addition compounds Me3SiF · (Pyridine)2, Me3SiCl · (Pyridine)2, MeSiCl3, · (2.5-Lutidine)2, MeSiCl3, · (2.6-Lutidine)2, (MeSiCl3)2 · 3.5-Lutidine, and the congruently melting compounds MeSiCl3 · 2.4-Lutidine, MeSiCl3 · (3.5-Lutidine)2 was proven.
Reaktionen der Natrium-Komplexe aromatischer Ether mit Dichlor(diorganylamino)boranen/Reactions of Sodium Complexes of Aromatic Ethers with Dichloro(diorganylamino)boranes
Authors: Maringgele Walter , Meller Anton
Published: March 2015

The reaction of anisole with Na/K-alloy and subsequent reaction with dichloro(diisopropyl-amino)borane yields diisopropylamino(diphenoxy)borane (1). In reacting the sodium complex of 1-or 2-m ethoxynaphthalene, respectively, with dichloro(diorganylamino)boranes the ether bond is cleaved. One obtains the methoxy-2-naphthoxy-diorganylam inoboranes (2a -d) besides the di-2-naphthoxy-diorganylam inoboranes (3a-e), the 2-naphthoxy-bis(diorganylamino)boranes (4a-b) and the solvated sodium-2-naphtholate (6). By-products are 1,2-bis[(diisopropylamino)-1- or 2-naphthoxyboryl]ethyne derivatives 5a and 5b, terized analytically and spectroscopically (MS; NMR: 1H, 11B, 13C).
Notizen: Synthese Dicyclopentadienyl-Titan(IV)- substituierter Carbodiimide/Syntheses of Dicyclopentadienyl-Titanium(IV) Substituted Carbodiimides
Authors: Plenio Herbert , Roesky Herbert W.
Published: March 2015

(MeCp)2Ti(NCO)(NCNSiMe3) (1), Cp2Ti(NCO)(NCNSiMe3) (2) and Cp2Ti(NCNSiMe3)2 (3) are formed by the reaction of (MeCp)Ti(NCO)2 and Cp2Ti(NCO)2 with LiN(SiMe3)2. All three new com pounds are thermally and hydrolytically unstable red solids that were characterized by mass spectrometry. 1H NMR and elemental analysis.
Notizen: Phasendiagramme von Systemen, bestehend aus Aluminiumhalogeniden und Pyridiniumhalogeniden, III. Die Phasendiagramme der Systeme Aluminiumbromid-Pyridiniumiodid und Aluminiumchlorid-Pyridiniumbromid/Phase Diagrams of Aluminium Halide- Pyridinium Halide Systems, III. Determination of the Phase Diagrams Aluminium Bromide-Pyridinium Iodide and Aluminium Chloride-Pyridinium Bromide
Authors: Seemann Gerd , Hensen Karl
Published: March 2015

Phase equilibrium studies of the Lewis acid-base systems AlCl3/PyHBr and AlBr3/PyHI indicate the existence of congruently melting compounds of the molar ratios 1:1 and 2:3.

These results are quite different from those of our studies of the AlCl3/PyHCl and the AlBr3/PyHBr systems, in which four compounds in the molar ratios 1:1, 1:2, 1:3, and 2:3 could be detected.

The melting point of pyridinium iodide observed at 284,8 °C (decomp.) differs from the previously reported one.
Heterocyclische Siebenring-Verbindungen, XXXIY. Eine einfache Synthese von 1-Benzoxepin und 1-Benzothiepin / Heterocyclic Seven-Membered Ring Compounds, XXXIV. A Simple Synthesis of 1-Benzoxepine and 1-Benzothiepine
Authors: Hofmann Hans , Djafari Hamid
Published: March 2015

Base induced isomerization of 1-benzoxepin-5(2H )-one (1a ) yields 1-benzoxepin-5(4H )-one (4a) which gives the unsaturated alcohol 5a on treatment with Ce(III)chloride/sodiumboranate. Subsequent reaction of 5a with p-toluenesulfonylchloride and then, without isolation of the intermediate, with base yields 1-benzoxepine (6 a). With tetracyanoethylene 6a forms the corresponding diene-adduct. The same reaction sequence was realized in the analogous sulfur series, yielding 1-benzothiepine (6 b).
Chemie an starren Grenzflächen, 11. Aerosile mit kovalent beweglich und starr verknüpften Fluoreszenzträgern / Chemistry on Rigid Surfaces, 11. Aerosils with Covalently Movable and Rigid Linked Fluorophors
Authors: Horner Leopold , Hallenbach Werner , Vogt Manfred
Published: March 2015

Abstract 5-Dimethylamino-1-naphthalene-carbonic acid chloride (1), the analog of dansylchloride, is synthesized. With diazomethane the diazoketone 2 is obtained. The modified aerosil A is formed by the interaction of 1 with amino-aerosil. The density of the coverage is available a) chemically by dissolving the inorganic matrix of A with H2F2 and spectroscopic determination of the formed n-butylamide 9, b) by fluorescence spectroscopy and c) by U V spectroscopy.

Silanole groups both in organic substituted compounds and in aerosil react with the fluorescent silanes 6 and 7 using CsF/imidazole-catalysis forming the corresponding siloxanes according to (4 b) and (8).

The modified aerosils C, D and E are prepared in this way and characterized.

The functionalization of amino-aerosil with 7-chloro-4-nitrobenzeno furazane (10) leading to the modified aerosil B is unsatisfactory.
Synthese und Struktur von K2Au3, einer neuen Phase im System Kalium—Gold / Synthesis and Structure of K2Au3, a New Phase in the System Potassium —Gold
Authors: Krieger-Beck Petra , Brodbeck Andreas , Strähle Joachim
Published: March 2015

K2Au3 is obtained from the elements in a sealed Ta am poule as air-sensitive needles with a golden lustre. It crystallizes in the orthorhombic space group Immm with the lattice constants a = 487.5(2), b = 545.4(2), c - 1000.4(4) pm; Z = 2. The structure is com posed of planar layers of Au atoms at z = 0 and 0.5 and intercalated K atoms. The layers consist of triangles and hexagons with Au -Au distances between 268.8 and 280.2 pm. The K atoms have ten Au neighbours with distances from 334 to 389 pm.