bluuebunny/crossref_metadata_2025 huggingface dataset:
Dysprosiumcarbidiodide Dy10(C2)2I18, Dy4(C2)I6 und Dy12(C2)3I17 / Dysprosium Carbide Iodides Dy10(C2)2I18, Dy4(C2)I6, and Dy12(C2)3I17
Authors: Mattausch Hansjürgen , Hoch Constantin , Simon Arndt
Published: February 2015

The title compounds are formed by reaction of Dyl3, Dy metal and C in stoichiometric amounts in closed Ta ampoules, Dy10(C2)2I18 at 930 °C 7days, Dy4 (C2)I6 at 950 °C for 6 days and Dy12(C2)3I17 at 900 °C for 11 days as pure samples according to X-ray powder diffraction. Dy10(C2)2I18 crystallizes in space group P21/c with a = 10.470(2), b = 17.152(3), c = 13.983(3) Å and β = 121.14(3)°, Dy4(C2)I6 in Pnnm with a = 13.622(3), b = 14.335(3) and c = 8.396(2) Å , and Dy12(C2)3I17 in C2/c with a = 19.149(4), b = 12.069(2), c = 18.595(4) Å , and β = 90.54(3)°. The crystal structure of Dy10(C2)2I18 is composed of Dy double octahedra centered by (C2)6− groups (ethanide) with the iodide ions above the edges and the corners of the Dy10(C2)2 units. In Dy4(C2)I6 the Dy atoms form chains of trans-edge sharing octahedra with embedded (C2) groups. In the structure of Dy12(C2)3I17 alternately cis-, trans-edge-condensed Dy6 octahedra centered by (C2) groups occur. The iodine atoms surround the chains like in the M6X12 cluster and interconnect neighboring chains.
Magnetic and Electrical Properties of the Intermetallic Compounds RE2Au2Sn (RE = Y, Dy–Tm, Lu) and RE2Au2In (RE = Ho, Lu)
Authors: Pöttgena Rainer , Kremerb Reinhard K. , Rayaprola Sudhindra , Heyinga Birgit , Hoffmanna Rolf-Dieter
Published: February 2015

The intermetallic compounds RE2Au2Sn (RE = Y, Dy-Tm, Lu) and RE2Au2In (RE = Ho, Lu) were synthesized from the elements via arc-melting and subsequent annealing at 1070 K for 10 days. Depending on the size of the rare earth element, the compounds crystallize with the Mo2B2Fetype (space group P4/mbm) or the Er2Au2Sn structure (space group P42/mnm), a superstructure of Mo2B2Fe. Temperature dependent susceptibility measurements of Y2Au2Sn, Lu2Au2Sn, and Lu2Au2In indicate Pauli paramagnetism compatible with the metallic behavior deduced from resistivity measurements. Ho2Au2In and RE2Au2Sn (RE = Dy-Tm) show Curie-Weiss behavior above 50 K with experimental magnetic moments close to the free ion values of the trivalent rare earth elements. The compounds Ho2Au2In, Dy2Au2Sn, Ho2Au2Sn, and Er2Au2Sn, undergo magnetic ordering at 20(1) (F), 16(1) (AF), 8(1) (AF), and 4.5(1) K (AF), respectively. Tm2Au2Sn remains paramagnetic down to 2 K.
Structural Investigation of ScAuSi and ScAuGe using 45Sc Solid State NMR
Authors: Sebastian C. Peter , Zhang Long , Eckert Hellmut , Pöttgen Rainer
Published: February 2015

The hexagonal scandium compounds ScAuSi (P6̄m2, a = 421.7(1), c = 680.7(1) pm) and ScAuGe (P63mc, a = 431.03(9), c = 685.5(1) pm) were synthesized in X-ray pure form via arc-melting of the elements. The structures are derived from the AlB2-type. The gold and silicon (germanium) atoms build up strongly puckered layers of Au3Si3 and Au3Ge3 hexagons. Due to a different puckering pattern and stacking sequence of the hexagons, the ScAuGe structure has one and the ScAuSi structure two crystallographically independent scandium sites, which can be unambiguously distinguished on the basis of 45Sc-29Si magnetic dipole-dipole interactions measured in a site selective fashion on an isotopically enriched material by solid state NMR.
Gemischte Erdalkalimetall-Trielide AIIM1III
x M2 III
2– x (AII = Ca, Sr, Ba; MIII = Al, Ga, In). Strukturchemische und bindungstheoretische Untersuchungen / Mixed Alkaline Earth Trielides AIIM1III
x M2III
2−x (AII = Ca, Sr, Ba; MIII=Al, Ga, In). A Structural and Theoretical Study
Authors: Harms Wiebke , Wendorff Marco , Röhr Caroline
Published: February 2015

The binary alkaline earth trielides of the composition AIIMIII 2 exhibit a puzzling variety of structure types ranging from electron precise Zintl compounds like CaIn2 and KHg2 (both with networks of four-bonded M− entities) and the AlB2 structure type (with graphite analogue M sheets) to the cubic Laves phases e. g. of CaAl2. The examination of the phase stabilities of mixed compounds AM1III
x M2III
2−x of two trielides allows to separate the stability ranges in a structure map by taking the electronegativity differences of MIII and AII (Δ EN) and the radius ratios (RR = rM/rA) into account: The CaIn2-type is stable at comparatively large RR, for example over the whole range CaGa2 -CaIn2 and even up to CaAl0.6Ga1.4 and CaAl1.2In0.8, and in SrIn2, together with a limited substitution of In by Al or Ga. The KHg2-type is observed in a region of lower RR: In BaIn2, a substitution of In by 50% Al and 30% Ga is possible without a general structure change, in SrAl2 this holds for a content of up to 50% In. At high Δ EN and low RR values (e. g. Sr/Ba-Ga), the ideal AlB2 structure type exhibits a distinct stability range; only for small RR around CaAl2 the MgCu2-type is stable. FP-LAPWband structure calculations of the binary trielides allow to explain the structural changes qualitatively. In the case of the electron precise phases forming the CaIn2, KHg2 or AlB2 structure type, details of the bonding situation (such as M-M distances) as well as differences to other isoelectronic compounds can be rationalized taking the incomplete charge transfer from the alkaline earth towards the triel elements into account. This causes a partial depopulation of some of the bonding and a population of predominantly antibonding states.
Unsymmetrical Single-Component Nickel 1,2-Dithiolene Complexes with Extended Tetrachalcogenafulvalenedithiolato Ligands
Authors: Anyfantisa George C. , Papavassiliou George C. , Aloukos Panagiotis , Couris Stelios , Weng Yufeng F. , Yoshino Harukazu , Murata Keizo
Published: February 2015

The unsymmetrical complexes Ni(dmdt)(dmio) and Ni(dmstfdt)(dmio) (dmdt = dimethyltetrathiafulvalenedithiolate, dmstfdt = dimethyldiselenadithiafulvalenedithiolate, dmio = 1,3-dithiol-2-one- 4,5-dithiolate) were prepared and characterized analytically and spectroscopically. The complexes exhibit strong third-order nonlinear optical response in the visible and near-infrared spectral regions.
Spin-Spin Coupling Constants 1J(15N,11B) in Boron-Nitrogen Compounds. Experimental Data and DFT Calculations
Authors: Wrackmeyer Bernd , Tok Oleg L.
Published: February 2015

Boron-nitrogen compounds were studied with respect to indirect nuclear 15N-11B spin-spin coupling (1J(15N,11B)). Some new experimental data were determined for aminoboranes and tetra-Npyrrolylborate, and a variety of compounds with B-N single, double and triple bonds were examined using DFT methods for the calculation of 1J(15N,11B) at the B3LYP/6-311+G(d,p) level of theory. The calculations predict magnitude and sign of 1J(15N,11B) reasonably well, and the Fermi contact term was found to be dominant. A positive sign of 1J(15N,11B) was calculated in the case of 1-azacloso- dodecaborane(12), in contrast to all other compounds studied.
The Sum of van der Waals Radii – A Pitfall in the Search for Bonding
Authors: Schiemenz Günter Paulus
Published: February 2015

The most widely used criterion for the evaluation of chemical bonding, especially of weak bonding, are interatomic distances shorter than the sum of the van derWaals radii, d(X···Y)<Σr(vdW)[X,Y]. The shortcomings of these radii are, however, so serious, that illicit conclusions are easily arrived at. It is proposed to discard the ‘shorter than Σr(vdW)’ criterion altogether and to rely on alternative criteria.
Synthesis of 3,4,5-Trimethoxy-4’-hydroxystilbene Derivatives and Crystal Structure of Ethyl {4-[(E)-2-(3,4,5-trimethoxyphenyl)vinyl]phenoxy}acetate
Authors: Baolin Li , Jian Guo , Xiquan Zhang , Yitian Lai , Huaiming Hu
Published: February 2015

Several new 4’-O-substituted derivatives of 3,4,5-trimethoxy-4’-hydroxystilbene were synthesized and characterized by their IR and NMR spectra. The crystal structure of ethyl {4-[(E)-2-(3,4,5-trimethoxyphenyl) vinyl]phenoxy}acetate, one of these stilbene derivatives, has been solved by singlecrystal X-ray structure analysis. The results show that all carbon and oxygen atoms in the molecule are nearly coplanar except C(16), and molecules stack to a column arrangement owing to C-H···π interactions. Pairs of these columns are linked by other molecules, and these linker molecules themselves also produce a column along the other direction. A puckered cyclic tetramer R4
4 (46) is formed and the tetramer propagates itself via intermolecular hydrogen bonds and C-H···π interactions. In this way, molecules are interrelated and assembled to a two-dimensional layer structure.
Unusual Tropane Alkaloid Pattern in Two African Convolvulaceous Species. Phytochemistry and Chemotaxonomy of the Convolvulaceae, Part 20 [1]
Authors: Ott Sonja C. , Tofern-Reblin Britta , Jenett-Siems Kristina , Siems Karsten , Müller Frank , Hilker Monika , Onegi Bernardina , Witte Ludger , Eicha Eckart
Published: February 2015

An unusual and complex tropane alkaloid pattern has been detected in the root bark of Astripomoea malvacea and in the whole plant of Falkia repens (Convolvulaceae) by GC-MS analysis. The specific profile of both species is characterized by the presence of aliphatic 3- acyloxytropanes/-nortropanes (exclusively in A. malvacea; predominantly in F. repens in cooccurrence with a few aromatic as well as arylalkyl acyl congeners). The principal alkaloid of A. malvacea, astrimalvine A N-oxide [3β -(3-tigloyloxy-2-methylbutyryloxy)tropane N-oxide], isolated and structurally elucidated by detailed spectroscopic analysis, represents the first N-oxide of a 3β -tropanol derivative in the Convolvulaceae. Its minor tertiary congener astrimalvine B [3β -(3-hydroxy-2-methylbutyryloxy)tropane] turned out to be a metabolite of both convolvulaceaous species. This is the first phytochemical report on the African genera Astripomoea and Falkia.
N,N'-Di(alkyloxy)imidazolium Salts: New Patent-free Ionic Liquids and NHC Precatalysts
Authors: Laus Gerhard , Schwärzler Alexander , Schuster Philipp , Bentivoglio Gino , Hummel Michael , Wurst Klaus , Kahlenberg Volker , Lörting Thomas , Schütz Johannes , Peringer Paul , Bonn Günther , Nauer Gerhard , Schottenberger Herwig
Published: February 2015

1-Hydroxyimidazole-3-oxides (2-H, 2-Me) were alkylated with (RO)2SO2 (R =Me, Et) to give the new 1,3-di(alkyloxy)imidazolium cations which were isolated as hexafluorophosphates. Ion metathesis yielded new hydrophobic ionic liquids (bis(trifluoromethanesulfonyl)imides, tris(pentafluoroethyl) trifluorophosphates). Bromination afforded 2-bromo derivatives which were converted to Ni and Pd N-heterocyclic carbene complexes by oxidative insertion. Fifteen crystal structures were determined by X-ray diffraction. The N-alkyloxy groups are twisted out of the imidazole ring plane and adopt either syn or anti conformations in the solid state.
Ethynylthioamide Complexes: Synthesis, Reactivity and an Unusual Coupling Reaction with Diethylaminopropyne
Authors: Szesni Normen , Drexler Matthias , Weibert Bernhard , Fischer Helmut
Published: February 2015

The reaction of [(CO)5Cr(THF)] with propynethioic acid amides, R-C≡C-C(=S)NMe2 (R = H, SiMe3), yields the thioamide complexes [(CO)5Cr-S=C(NMe2)C≡C-H] (1a) and [(CO)5Cr- S=C(NMe2)C≡C-SiMe3] (1b). Treatment of solutions of 1a or 1b with methyllithium generates, via deprotonation or desilylation, the lithium salt Li[(CO)5Cr-S=C(NMe2)C≡C] (2). On filtration over silica, 2 is readily reprotonated. Complex 1a is inert towards methanol, however, adds diethylamine across the C≡C bond to give the thioacrylamide complex [(CO)5Cr-S=C(NMe2)C(H)=C(H)NMe2] (3). Thiourea displaces the thioamide ligand to give [(CO)5Cr-S=C(NH2)2] (4). Complex 1a reacts with half an equivalent of diethylaminopropyne in a three-component coupling to form the homobinuclear complex [(CO)5Cr-S=C(NEt2)-C(CH3)=C(H)-C(H)=C(NMe2)-C≡C-C(NMe2)=S- Cr(CO)5] (5) in high yield. The solid state structures of complexes 1a and 5 were established by X-ray structural analyses.
Theoretical Study of Ethylene Addition to O=W(=CH2)(CH3)2
Authors: Haunschild Robin , Frenking Gernot
Published: February 2015

Quantum chemical calculations using density functional theory at the B3LYP level of theory were carried out to investigate the reaction pathways for the addition of ethylene to WO(CH3)2(CH2) (W1). The results are compared to those of previous theoretical studies of the ethylene addition to OsO3(CH2) (Os1) and ReO2(CH3)(CH2) (Re1). The theoretically predicted reactions pathways exhibit significant differences. The energetically most favourable reaction of the tungsten system W1 is the [2+2]W,C addition across theW=C double bond yielding the metallacyclobutane W3a which then rearranges to the slightly more stable isomer W3b. The [2+2]Re,C addition of the rhenium compound yielding the metallacyclobutane Re3a has the lowest activation barrier for the ethylene addition to the rhenium system, but the reaction is endothermic while the exothermic formation of the more stable isomer Re3b has a much higher activation barrier. The [3+2]C,O addition Os1+C2H4→Os2 is the thermodynamically most favorable reaction of the osmium compound.
Synthesis and Characterization of New Diiron and Diruthenium μ-Aminocarbyne Complexes Containing Terminal S-, P- and C-Ligands
Authors: Albano Vincenzo G. , Busetto Luigi , Marchetti Fabio , Monari Magda , Zacchini Stefano , Zanotti Valerio
Published: February 2015

The diiron aminocarbyne complexes [Fe2{μ-CN(Me)(R)}(μ-CO)(CO)(NCMe)(Cp)2][SO3CF3] (R = Xy1, 1a; R = Me, 1b; R = CH2Ph, 1c; Xy1 = 2,6-Me2C6H3) undergo replacement of the coordinated nitrile by halides, diethyldithiocarbamate, and dicyanomethanide to give [Fe2{μ-CN(Me) (R)}(μ-CO)(CO)(X)(Cp)2] complexes (R = Me, X = Br, 4a; R = Me, X = I, 4b; R = CH2Ph, X = Cl, 4c; R = CH2Ph, X = Br, 4d; R = CH2Ph, X = I, 4e; R = Xy1, X = SC(S)NEt2, 5a; R = Me, X = SC(S)NEt2, 5b; R = Xy1, X = CH(CN)2, 7), in good yields. The molecular structure of 5a shows an unusual η1 coordination mode of the dithiocarbamate ligand. Similarly, treatment of [M2{μ-CN(Me) (R)}(μ-CO)(CO)(NCMe)(Cp)2][SO3CF3] (M = Fe, R = Xy1, 1a; M = Fe, R = Me, 1b; M = Ru, R = Xy1, 2a; M = Ru, R = Me, 2b) with a series of phosphanes generates the cationic complexes [M2{μ- CN(Me)(R)}(μ-CO)(CO)(P)(Cp)2][SO3CF3] (M = Fe, R = Xy1, P = PPh2H, 6a; M = Fe, R = Xy1, P = PPh3, 6b; M = Fe, R = Xy1, P = PMe3, 6c; M = Fe, R = Me, P = PMe2Ph, 6d; M = Fe, R = Me, P = PPh3, 6e; M = Fe, R = Me, P = PMePh2, 6f; M = Ru, R = Xy1, P = PPh2H, 6g; M = Ru, R = Me, P = PPh2H, 6h), in high yields. The molecular structure of 6a has been elucidated by an X-ray diffraction study. The reactions of [Fe2{μ-CN(Me)(Xyl)}(μ-CO)(CO)(NCR′)(Cp)2][SO3CF3] [R′ = Me, 1a; R′ = tBu, 3] with PhLi and PPh2Li yield [Fe2{μ-CN(Me)(Xy1)}(μ-CO)(CO)(Ph)(Cp)2] (8) and [Fe2{μ-CN(Me)(Xy1)}(μ-CO)(CO)(PPh2)(Cp)2] (9), respectively. The molecular structure of 8 has been ascertained by X-ray diffraction. Conversely, the reaction of 1a with MeLi generates the aminoalkylidene compound [Fe2{C(Me)N(Me)(Xy1)}(μ-CO)2(CO)(Cp)2] (10).

Finally, the acetone complex [Fe2{μ-CN(Me)(Xy1)}(μ-CO)(CO)(OCMe2)(Cp)2][SO3CF3] (12) reacts with lithium acetylides to give complexes [Fe2{μ-CN(Me)(Xy1)}(μ-CO)(CO)(C≡CR)(Cp)2] (R = p-C6H4Me, 11a; R = Ph, 11b; R = SiMe3, 11c), in high yields. Filtration through alumina of a solution of 11a in CH2Cl2 results in hydration of the acetylide group and C-Si bond cleavage, affording [Fe2{μ-CN(Me)(Xy1)}(μ-CO)(CO){C(O)Me}(Cp)2] (12).
Solvent-free Substitution Reactions of Solid Phosphines with (η5-RC5H4)Fe(CO)2I (R = H, Me) Complexes
Authors: Munyaneza Apollinaire , Bala Muhammad D. , Coville Neil J.
Published: February 2015

Reactions of (η5-RC5H4)Fe(CO)2I (R = H, Me) complexes with phosphine ligands PR′3 (R′ = Ph, m-Tol, p-C6H4OMe, p-C6H4Cl, p-C6H4F) have been performed under solvent-free conditions in the melt phase and generally yielded the ionic products [(η5-RC5H4)Fe(CO)2PR′3]I rather than the CO substituted products (η5-RC5H4)Fe(CO)(PR′3)I. The complexes have been characterised by IR, NMR and MS techniques. By contrast, the same reactions studied in benzene solution have yielded mainly the CO substitution products. Factors that affect the solvent-free reaction include variation in R and R′ , reaction temperature and the addition of [CpFe(CO)2]2 as a catalyst. The mechanism of the reaction for the formation of the ionic complex is proposed to go via a 19 electron intermediate. This is in contrast to the reaction in bezene that occurs via a 17 electron intermediate, clearly indicating the role of the melt phase in the reaction.
Bis-Imide Derivatives of the Heterometallic Alkoxide Li4Ti4O4(OiPr)12
Authors: Fric Helmut , Schubert Ulrich
Published: February 2015

The imide derivatives Li4Ti4O2(NR)2(OiPr)12 (R = CH2C6H5, C6H11, C4H9) were obtained either by reaction of the amine adduct Ti2(OiPr)8(H2NR)2 with lithium diiso- propylamide or butyllithium, or when the primary amine was first reacted with the base and then with Ti(OiPr)4. The structures of the imide derivatives are the same as that of Li4Ti4O4(OiPr)12 (= Li4Ti4(μ2-O)2(μ5-O)2(μ2-OiPr)4(μ3- OiPr)4(OiPr)4) with the two μ2-oxo groups replaced by two μ2-NR groups.
One-dimensional Hydrogen-bonded Chloride-Hydrate Assembly {[(H2O)4Cl2]2–}∞
Authors: Dai Ji-Xiang , Wu Fang-Hui , Yao Wen-Rui , Zhang Qian-Feng
Published: February 2015

A hydrogen-bonded chloride-hydrate assembly {[(H2O)4Cl2]2−}∞ has been ion-countered by the complex cations [Fe([9]aneS3)2]2+ ([9]aneS3 = 1,4,7-trithiacyclononane). In {[(H2O)4Cl2]2−}∞, four water molecules and two chloride ions are self-assembled to form a one-dimensional supramolecular array of O-H···O and O-H···Cl hydrogen bonding, which consists of fused fourand six-membered rings. The discrete cation [Fe([9]aneS3)2]2+ has a nearly regular octahedral FeS6 core with an average Fe-S bond length of 2.2586(5) Å .
Synthesis, Crystal Structure and Properties of CuBr(2,3-dimethylpyrazine) Coordination Polymers
Authors: Jeß Inke , Taborsky Petr , Näthera Christian
Published: February 2015

Reaction of CuBr with an excess of 2,3-dimethylpyrazine in acetonitrile leads to the formation of the literature known ligand-rich 1 : 1 compound poly[μ2-bromo-μ2-2,3-dimethylpyrazine- N,N′-copper(I)] (1). On heating this compound in a thermobalance a transformation into the new ligand-deficient 2 : 1 compound poly[di-μ3-bromo-μ2-2,3-dimethylpyrazine-N,N′-dicopper(I)] (3) is observed, which later was also prepared in solution. This compound crystallizes in the monoclinic space group P21/n with all atoms in general positions. In the crystal structure the Cu atoms are surrounded by three Br atoms and one 2,3-dimethylpyrazine ligand within a distorted tetrahedron. The tetrahedra are connected via common Br edges into CuBr double chains, which are connected by the ligands into layers located in the ab plane. The formation of compounds 1 and 3 was also investigated in solution. The results have shown that compound 1 can only be prepared if an excess of the ligand is used. If CuBr and the ligand are reacted in a ratio of 1 : 1, in the beginning the literature known ligand-deficient 3 : 2 intermediate catena[tribromo-μ2-bis(μ2-2,3-dimethylpyrazine- N,N′)-tricopper(I)] (2) is obtained, which transforms within minutes into compound 3. If a crystalline suspension of compound 1 is stirred in acetonitrile a transformation into the most stable compound 3 is also observed. The luminescence properties of compounds 1 and 3 were investigated. The complexes show differences mainly in the emission spectra.
Preparation and Characterization of Mononuclear Ni Complexes of Tetradentate Amine-thioether and Amine-thiolate Ligands
Authors: Fritz Thorsten , Steinfeld Gunther , Kersting Berthold
Published: February 2015

A short route for the preparation of tetradentate amine-thioether and amine-thiolate ligands derived from thiosalen is reported. The ligating properties of several of the synthesized ligands towards Ni(II) has been examined. The diamine-dithiophenolate ligands (L6)2− [H2L6 = N,N′-dimethyl-N,N;-di(2- mercaptobenzyl)-ethane-1,2-diamine] and (L7)2− [H2L7 = N,N′-di(2-mercaptobenzyl)-piperazine] support the formation of four-coordinate NiIIN2S2 complexes [NiII(L6)] (10) and [NiII(L7)] (11). By contrast, the amine-thioethers 2 [N′,N″-bis(2-(tert-butylthio)benzyl)ethane-1,2-diamine], L2 [8,11- diaza-5,13-dibenzo-1,4-dithia-cyclotetradecane] and its N-methylated derivative L2,Me were found to produce the six-coordinate Ni(II) complexes [NiIICl2(2)2] (9), [NiII
2(μ-Cl)2(L2)2][ClO4]2 (12), [NiII(NCS)2(L2)] (13), and [NiIICl2(L2,Me)] (14). The results of IR, NMR and UV/vis spectroscopy and the crystal structures of complexes 9 - 13 are reported.
Nitroimidazoles, Part 3. Synthesis and anti-HIV Activity of New N-Alkyl-4-nitroimidazoles Bearing Benzothiazole and Benzoxazole Backbones
Authors: Al-Soud Yaseen A. , Al-Sa’doni Haitham , Amajaour Houssain A. S. , Al-Masoudib Najim A.
Published: February 2015

A series of 4-nitroimidazole derivatives bearing substituted piperazines (5, 8, 9, 12, 14, 16, 17, and 19 - 21) were synthesized with the aim to develop new non-nucleoside reverse transcriptase inhibitors (NNRTIs). The newly synthesized compounds were assayed against HIV-1 and HIV-2 in MT-4 cells. All compounds are inactive, except compound 21 which showed inhibition of HIV-1 with EC50 0.20 μg/mL, and therapeutic indexes (SI) of 12.
Chemoselective One-pot Conversion of Primary Alcohols to their Bis(indolyl)methanes Promoted by Bi(NO3)3·5H2O
Authors: Khosropour Ahmad R. , Mohammadpoor Iraj , Khodaei Mohammad M. , Ghanbary Parvin
Published: February 2015

A new, “green” and efficient one-pot protocol for the synthesis of bis(indoyl)methanes from primary alcohols using Bi(NO3)3 ·5H2O is described. This procedure performs chemoselectively through a solvent-free reaction and the products are obtained in high to excellent yields.
Mannich Bases as Synthetic Intermediates: Synthesis of 3- and 4-Functionalized 2-Pyrazolines
Authors: Afsah Elsayed M. , Kandeel Ez-el-Din M. , Khalifa Mona M. , Hammouda Waleed M.
Published: February 2015

The reaction of styryl ketonic Mannich bases 2a - c with phenylhydrazine leads to 3-functionalized 2-pyrazolines 4 or 6 depending on the reaction conditions. 3-[β -(Arylamino)ethyl]-2-pyrazolines 8a,b were obtained via transamination between the methiodide salt 7 and primary arylamines. Treatment of 1-(p-anisyl)-1,2,5-tri(N-piperidino)pentan-3-one (11) with phenylhydrazine affords the 3,4-difunctionalized 2-pyrazoline 12. The reactions of the keto bases 19 or 21 with hydrazines lead to 4-functionalized 2-pyrazolines 20 and 22, the N-Mannich bases 23 and 24 are obtained from 22a. The synthesis of 3-[β -(phenylthio)ethyl]-2-pyrazolines 28a,b has been achieved by treating 26 or 27 with phenylhydrazine.
Studies of Dihydropyridines by X-Ray Diffraction and Solid State 13C NMR
Authors: Morales-Ríos Martha S. , Martínez-Richa Antonio , Hernández-Gallegos Zurisaddai , Hernández-Barragán Angelina , Vera-Graziano Ricardo , Joseph-Nathan Pedro
Published: February 2015

Fourteen dimethyl 4-aryl-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylates (DHPs) were evaluated by means of single crystal X-ray diffraction in order to investigate the effects of the structure in the crystals on the solid state 13C NMR chemical shifts. These include the analysis of three DHPs containing two molecules per asymmetric unit. The chiral rotamer unit generated by the s-cis/s-trans orientation of the carbonyl groups, as well as by rotation of the 4-phenyl ring out of the bisecting plane containing the N1, C4, C7 atoms, resulted in a significant magnetic non-equivalence for the C2-CH3/C6-CH3 and the COOCH3 pairs of signals. The solid state 13C NMR data reveal that the substitution pattern of the phenyl ring has a marked effect on the extent to which the signals of the carbonyl carbon atoms and those of C-2/C-6 peaks are split.
Xylogranatin E, a New Phragmalin with a Rare Oxygen Bridge between C1 and C29, from the Fruit of a Chinese Mangrove Xylocarpus granatum
Authors: Wu Jun , Ding Haixin , Li Minyi , Zhang Si
Published: February 2015

Xylogranatin E, the second phragmalin with a rare oxygen bridge between C1 and C29 found in nature, was isolated from the fruit of a Chinese mangrove, Xylocarpus granatum. Its structure was determined by spectroscopic analysis. Complete assignment of 1H and 13C NMR data of xylogranatin E was achieved by 2D NMR techniques, including 1H-1H COSY, HSQC, HMBC and NOESY spectra.
Structure Refinement of CePtSi and Hydrogenation Behavior of CePdGe, CePtSi and CePtGe
Authors: Hermes Wilfried , Rodewald Ute Ch. , Chevalier Bernard , Pötgena Rainer
Published: February 2015

The intermetallic cerium compounds CePdGe, CePtSi, and CePtGe were synthesized from the elements by arc-melting and subsequent annealing. The structure of CePtSi was refined from single crystal X-ray diffraction data: LaPtSi-type (ordered α-ThSi2 version), 141md, a = 419.6(1) and c = 1450.0(5) pm, wR2 = 0.0490, 362 F2 values and 16 variables. The Pt-Si distances within the three-dimensional [PtSi] network are 242 pm, indicating strong Pt-Si interactions. Hydrogenation of the three compounds at 623 K and 4 MPa H2 gave no indication for hydride formation.
Synthesis and Single Crystal X-Ray Structure of Ethyl 2-(1,3-Benzoxazol- 2-yl)-5-oxo-3-(4-toluidino)-2,5-dihydro-4-isoxazolecarboxylate
Authors: Souldozi Ali , Khalafy Jabbar , Marjani Ahmad Poursattar , Ślepokura Katarzyna , Lis Tadeusz , Ramazani Ali
Published: February 2015

Ethyl 5-oxo-3-(4-toluidino)-2,5-dihydro-4-isoxazolecarboxylate was prepared from the reaction of diethyl 2-(4-toluidinocarbothioyl)malonate with hydroxylamine. Its reaction with 2- chlorobenzoxazole gave the corresponding N-substituted isoxazolone. The structure of the final product 4 was confirmed by IR, 1H and 13C NMR spectroscopy and mass spectrometry, and by X-ray single crystal structure determination.
Secondary Interactions in Bromomethyl-substituted Benzenes: Crystal Structures of Three α,α′-Bis-bromoxylenes, 1,2,3,5-Tetrakis(bromomethyl)benzene, and 1,2,4,5-Tetrakis(bromomethyl)benzene
Authors: Jones Peter G. , Kuś Piotr
Published: February 2015

X-Ray structure determinations of all three isomers of bis(bromomethyl)benzene and of two isomeric tetrakis(bromomethyl)benzenes show that the packing of the molecules is determined principally by interactions of the bromomethyl groups (C-H· · ·Br and Br· · ·Br), except for ortho-bis (bromomethyl)benzene, in which C-H· · ·π interactions play a major role.
Synthesis, Structure and Acid-Base Behaviour of Some 4-Hydroxycoumarin Derivatives
Authors: Stanchev Stancho , Maichle-Mössmer Cäcilia , Manolov Ilia
Published: February 2015

The compound 3,3′-[(4-hydroxy-3-methoxy-5-nitrophenyl)methylene]-bis(4-hydroxy-2H-1- benzopyran-2-one) (1) crystallizes in the monoclinic system, space group P21/n, with cell constants a = 16.859(4), b = 6.1624(15), c = 25.164(4) Å , β = 98.019(19)°. The two 4-hydroxycoumarin fragments are intramolecularly hydrogen-bonded between hydroxyl and carbonyl groups. The pH-dependent color changes of 4-hydroxycoumarin derivatives were studied by means of potentiometric and spectrophotometric titration. On the basis of the results obtained, the use of 3,3′-[(4-hydroxy-3- methoxy-5-nitrophenyl)methylene]-bis(4-hydroxy-2H-1-benzopyran-2-one) as an indicator in alkalimetry and acidimetry is proposed.
Xylodiol, a New Atisane Diterpenoid from Xylopia Langsdorffiana St.-Hil. & Tul. (Annonaceae)
Authors: Tavares Josean Fechine , Silva Marianna Vieira B. , Queiroga Karine F. , Diniz Margareth F. F. Melo , Filho José M. Barbosa , Haun Marcela , Melo Patrícia S. , Silvaa Marcelo Sobral da
Published: February 2015

Two diterpenes were isolated from the leaves of Xylopia langsdorffiana, the new ent-atisane- 7α,16α-diol named xylodiol (1) and the known 8 (17),12E,14-labdatrien-18-oic acid (2). The structures of these isolates were deduced by spectroscopic data interpretation. Compound 2was less toxic than xylodiol on V79 cells and hepatocytes.
Bafe3.39(5)Ru2.61(5)O11 And BaCo1.85(6)Ru4.15(6)O11. Preparation, Crystal Structures, And Magnetic And Transport Properties Of Quaternary Transition Metal Oxoruthenates
Authors: Niewa Barbara Schüpp , Shlyk Larisa , Kryukov Sergej , De Long Lance E. , Niewa Rainer
Published: February 2015

Black plate-like single crystals of BaFe3.39(5)Ru2.61(5)O11 and BaCo1.85(6)Ru4.15(6)O11 were grown from a BaCl2 flux [hexagonal, space group P63/mmc (No. 194), Fe: a = 5.856(1), c = 13.587(1) Å , R1 = 0.029, wR2 = 0.084; Co: a = 5.842(1), c = 13.573(3) Å, R1 = 0.033, wR2 = 0.075]. The crystal structures contain two crystallographic sites with mixed Ru and Fe/Co occupation of different level in octahedral coordination and one site purely occupied by the respective 3d metal. The latter position is in trigonal bipyramidal coordination, with some indication for a displacement of the metal atom towards tetrahedral coordination. According to the charge balance, the ruthenium atoms are incorporated with different electronic situations in the two Ru containing sites. The Co compound may be described as containing Co2+ and Ru5+ next to Ru3+. Magnetic susceptibility data support this assignment. According to magnetization measurements on oriented crystals, BaCo1.85(6)Ru4.15(6)O11 is a soft ferromagnetic material with low coercive field and a spontaneous magnetization below Tc = 105 K. It behaves as an electric conductor. However, BaFe3.39(5)Ru2.61(5)O11 is a narrow band semiconductor material with ferrimagnetic ordering at Tc = 440 K
High-Pressure Synthesis, Crystal Structure, And Properties Of δ-Ce(Bo2)3
Authors: Haberer Almut , Heymann Gunter , Huppertz Hubert
Published: February 2015

The cerium meta-oxoborate δ -Ce(BO2)3 was synthesized under high-pressure / high-temperature conditions of 3.5 GPa and 1050 °C in a Walker-type multianvil apparatus. The crystal structure was determined by single crystal X-ray diffraction data, collected at r. t. The compound crystallizes monoclinicly in the space group P21/c with the lattice parameters a = 422.52(8), b = 1169.7(2), c = 725.2(2) pm, and β = 91.33(3)°. The structure is isotypic to the recently published high-pressure phase δ -La(BO2)3, consisting exclusively of corner sharing [BO4]5− tetrahedra
High-Pressure Syntheses, Crystal Structures, And Thermal Behaviour Of β-Re(Bo2)3 (Re = Nd, Sm, Gd)
Authors: Emme Holger , Heymann Gunter , Haberer Almut , Huppertz Hubert
Published: February 2015

The compounds β -RE(BO2)3 [RE = Nd (neodymium meta-borate), Sm (samarium meta-borate) and Gd (gadolinium meta-borate)] were synthesized under high-pressure and high-temperature conditions in a Walker-type multianvil apparatus at 3.5 GPa (Nd), 7.5 GPa (Sm, Gd) and 1050 °C. The crystal structures were determined by single crystal X-ray diffraction data collected at r. t. (Sm, Gd) and at−73°C (Nd), respectively. The structures are isotypic with the already known ambient-pressure phases β -RE(BO2)3 (RE = (Tb, Dy) and the high-pressure phases β -RE(BO2)3 (RE = Ho-Lu)
Regio- And Stereoselective Addition Of Imides To Ethyl 3-Phenyl-2- Propynoate In The Presence Of Triphenylphosphine. Single Crystal X-Ray Structure Of Ethyl (Z)-2-(1,3-Dioxo-1,3,3A,4,7,7A-Hexahydro-2H-Isoindol- 2-Yl)-3-Phenyl-2-Propenoate
Authors: Mahyaria Amir Tofangchi , Shajari Nahid , Kazemizadeh Ali Reza , Ślepokura Katarzyna , Lis Tadeusz , Ramazani Ali
Published: February 2015

A one-pot synthesis of sterically congested N-vinyl imides in fairly high yields by the reaction of ethyl 3-phenyl-2-propynoate, imides and triphenylphosphine is reported. The structures of these compounds were confirmed by IR, 1H, and 13C NMR spectroscopy, and by a single crystal X-ray structure determination. The structural analysis of the products indicated that the reaction is regioand stereoselective
Synthesis And Single Crystal X-Ray Structure Of 2-(1,3,4-Oxadiazol- 2-yl)Aniline
Authors: Souldozi Ali , Ślepokura Katarzyna , Lis Tadeusz , Ramazani Ali
Published: February 2015

Reaction of 2-aminobenzoic acid with (N-isocyanimino)triphenylphosphorane proceeds smoothly at r. t. to afford 2-(1,3,4-oxadiazol-2-yl)aniline in high yield. The structure of this compound was confirmed by IR, 1H, and 13C NMR spectroscopy, mass spectrometry, and single crystal X-ray structure determination. The X-ray structural analysis of the product indicated that its aromatic rings are approximately co-planar
Two New Limonoids With A 3-O-β-Tigloyl Group From The Seeds Of The Chinese Mangrove Xylocarpus Granatum
Authors: Wu Jun , Li Minyi , Zhang Si , Xiao Qiang , Li Qingxin
Published: February 2015

A new mexicanolide and a new phragmalin, named 30α-hydroxyl xylogranatin A and xylogranatin E2, respectively, have been isolated from the seeds of a Chinese mangrove Xylocarpus granatum. Their structures were identified on the basis of spectroscopic data. Each of them has a 3-O-β -tigloyl group. The first complete assignments of 1H and 13C NMR data for these limonoids were achieved by means of 2D NMR techniques, including 1H-1H COSY, HSQC, HMBC and NOESY spectra
Trimethyl(4-Iodophenyl)Ammoniumiodid, Eine Hypervalente Verbindung Des Iods
Authors: Kuhn Norbert , Abu-Salem Qutaiba , Gädt Torben , Reit Steffi , Steimann Manfred
Published: February 2015

The crystal structure of trimethyl(4-iodophenyl)ammonium iodide (2), obtained from 4-iodo-N,N-dimethylaniline and methyl iodide, reveals the presence of weak hypervalent bonding of the iodine atom
“Covalent Magnetism” and Invar-like Behavior within Ternary Nitrides: An ab initio Study
Authors: Matar Samir F. , Houari Abdesalem , Belkhir Mohamed A. , Zakhour Mirvat
Published: February 2015

Magnetic properties and bonding analyses of perovskite structure-derived TFe3N (T = Ru, Os) nitrides have been investigated within density functional theory using both pseudo potential and all electron methods. At equilibrium, spin degenerate non-magnetic (NM) and ferromagnetic (FM) calculations of energy versus volume show that the ground state of the two compounds is ferromagnetic. Magnetic moments of Ru/Os and Fe, respectively, being situated at two different crystallographic sites are studied over a wide range of the cubic lattice parameter. The volume expansion indicates that iron atoms show itinerant magnetism while Ru and Os exhibit a localized behavior. Important magnetovolume effects are observed, with saturation of the magnetic moment reached in RuFe3N but not in OsFe3N. The electronic structure is visualized for the different binding characters Fe-N versus Ru/Os-N with the help of electron localization plots. The density of states of the ferromagnetic ground state is interpreted on the basis of a covalent magnetic model which goes beyond the Stoner rigid band model. An Invar-like behavior is predicted for the two nitrides.
Heavy Fermion Behaviour in Ce2Ni1.88Cd
Authors: Sampathkumaran Echur V. , Iyer Kartik K. , Mohapatra Niharika , Rayaprol Sudhindra , Pöttgen Rainer
Published: February 2015

The intermetallic compound Ce2Ni1.88Cd (tetragonal Mo2FeB2-type structure) has been investigated by magnetization (down to 1.8 K), electrical resistivity (ρ) and heat capacity (down to 0.5 K) measurements as a function of temperature (T). On the basis of these data, it is concluded that this compound is a heavy-fermion with a Kondo temperature in the range 235 - 250 K. Fermi-liquid behaviour expected for Kondo lattices is obeyed for the low temperature ρ data, but the ratio of the coefficient of the T2 term in the electrical resistivity to the square of the linear coefficient of the heat capacity is apparently low compared to the ‘universal ratio’ known for other cerium compounds, as though there is a breakdown of the Kadowaki-Woods relation in this compound. The value of this ratio falls in the range known for many intermediate-valent ytterbium compounds.
Superstructures in Room-temperature Ordered Deuterides CeCuSiDx and CeCuGeDx
Authors: Pasturel Mathieu , Weill François , Bobet Jean-Louis
Published: February 2015

Crystallographic superstructures in the deuterides CeCuSiD1.64(5) and CeCuGeH1.15(5) have been characterized by neutron diffraction. Deuterium atoms are inserted in [Ce3Cu] and [Ce3Si] or [Ce3Ge] tetrahedral sites available in the hexagonal ZrBeSi-related structure of these deuterides. A partial but ordered occupancy of these tetrahedra by D atoms induces the occurrence of superstructures along the c axis, and the CeCuXDy structures can be described with a c parameter multiplied by 3 and 7 for X = Ge and Si, respectively, in comparison with the c parameters of the ZrBeSi-type subcells.
Refinement of the Crystal Structures of Palladium-rich In-Pd Compounds by X-Ray and Neutron Powder Diffraction
Authors: Kohlmanna Holger , Ritter Clemens
Published: February 2015

The ternary indium palladium intermetallics In3Pd5, InPd2, and InPd3 have been synthesized by iodine-catalyzed reactions from the elements. Rietveld refinements on X-ray powder diffraction patterns provide the first accurate crystal structure data for In3Pd5 (Pbam, No. 55, a = 1104.20(2), b = 561.346(8), c = 424.263(6) pm, Rh5Ge3-type) and InPd2 (Pnma, No. 62, a = 561.676(6), b = 421.710(4), c = 822.78(8) pm, Co2Si-type). X-Ray powder diffraction apparently confirms the TiAl3 structure type proposed in the literature for InPd3. However, Rietveld refinement on neutron powder diffraction data reveals an In/Pd distributional disorder. Therefore, we describe the crystal structure of InPd3 in a AuCu-type model instead (P4/mmm, No. 123, a = 287.224(4), c = 380.079(7) pm), with mixed occupancy of one crystallographic site by 50% In and 50% Pd. In contrast to In3Pd5 and InPd2, which can be considered to be line compounds, InPd3 shows a non-negligible homogeneity range with unit cell volumes ranging from 0.126132(5) nm3 for the indium-rich to 0.125474(8) nm3 for the palladium-rich In1+xPd3−x phases. Mean In-Pd distances in these indium palladium intermetallics range from 272.3 pm (In1 in In3Pd5) with coordination number 8 for indium to 281.2 pm for 12-coordinated In in InPd3.
Ag10Te4Br3 –xClx and Ag10Te4Br3 –yIy: Structural and Electrical Property Tuning of a Mixed Conductor by Partial Anion Substitution
Authors: Nilges Tom , Bawohl Melanie , Lange Stefan
Published: February 2015

X-ray powder and EDX phase analyses, thermal analyses, impedance spectroscopic measurements, and crystal structure determinations of selected phases are reported to highlight the structural and electric properties of the solid solutions Ag10Te4Br3−xClx and Ag10Te4Br3−yIy. Bromide can be partially substituted by chloride or iodide up to x = 1.6 and y = 0.2, respectively, without changes in the structural properties of the tetramorphic, ion-conducting Ag10Te4Br3. Results from X-ray powder phase analyses have been complemented by data of single crystal structure determinations of selected samples. At r. t. the fully ordered γ -Ag10Te4Br3 structure type is realized in all chloride containing phases, but a partial iodide substitution leads to the stabilization of the disordered β -Ag10Te4Br3 structure type. Impedance spectroscopic measurements reveal a significant increase by one order of magnitude of the r. t. silver ion conductivity of Ag10Te4Br2.8I0.2 as compared with Ag10Te4Br3.
Magnetocaloric and Thermal Properties of Ho(Co1–xSix)2 Compounds
Authors: Sechovský Vladimír , Vasylyev Denys , Prokleška Jan
Published: February 2015

The specific heat and thermal conductivity of HoCo2 and Ho(Co0.95Si0.05)2 were measured as functions of temperature in several constant magnetic fields up to 8 T. From a specific-heat data analysis the isothermal entropy change and the magnetocaloric effect (MCE) have been evaluated in a wide temperature range for several values of the applied magnetic field. The considerable values of the magnetocaloric effect in the vicinity of the magnetic ordering transition are qualifying both compounds as suitable for magnetic refrigeration purposes. The magnetic phase transition temperature (TC) increases from 77 K for HoCo2 to 103 K for Ho(Co0.95Si0.05)2 while the large MCE in the vicinity of TC is maintained, which demonstrates ways of tuning the operating temperatures of the magnetic refrigerant.
Crystal Structure of the Trihydrate of the Neuraminidase Inhibitor C15H28N4O4 (Peramivir), a Potential Influenza A/B and Avian-influenza (H5N1) Drug
Authors: Keller Egbert , Krämer Volker
Published: February 2015

The crystal structure of the trihydrate of peramivir (C15H28N4O4), a potential influenza A/B and avian-influenza drug, has been determined. The structure, belonging to the tetragonal space group P42212 with Z = 32, a = 27.216(4), c = 23.084(5) Å, V = 17098(5) Å3, contains four organic molecules plus 12 partially disordered water molecules per asymmetric unit. 16 Organic molecules per unit cell form a kind of 1D infinite micelle separated from vicinal micelles by approximately planar water layers. During exposure to X-rays or under long-time storage on air peramivir trihydrate undergoes a phase transition to a structurally closely related phase with reduced water contents.
Synthesis and Solid-state Structure of a Star-shaped Oligobenzoate
Authors: Lehmann Matthias , Jahr Michael , Rüffer Tobias , Lang Heinrich
Published: February 2015

A star-shaped oligobenzoate with short peripheral propyloxy chains (1) forms single crystals 1· (Me2CO)0.5 with a triclinic unit cell from acetone. The oligobenzoate arms are fully extended, possessing only carboxy groups with s-trans conformation. Aliphatic chains and oligobenzoate scaffold do not nano-segregate as proposed for other derivatives which assemble in liquid crystalline phases, but instead, the polar arms occupy the voids between arms of neighboring stars. Although a model based on this scenario may rationalize the small column diameter in the LC phase of longchain derivatives, the low density of the resulting material points rather to the recently established representation with folded conformers self-assembling in columns by nano-segregation.
Orthoamide, LXIV [1]. Aromatenformylierungen mit Tris(dichlormethyl)amin und Oligoformylamin-Derivaten in Gegenwart von Supersäuren / Orthoamides, LXIV [1]. Formylation of Aromatic Compounds by Tris(dichloromethyl)amine and Oligoformylamine Derivatives in the Presence of Superacids
Authors: Kantlehner Willi , Leonhardt Sylvia , Ziegler Georg , Scherr Oliver , Kreß Ralf , Goeppert Alain , Sommer Jean
Published: February 2015

Tris(dichloromethyl)amine (4), triformamide (1) and tris(diformylamino)methane (“formylaalen”) (2) can be activated by addition of trifluoromethanesulfonic acid. The formylating systems thus formed transform activated aromatic compounds, such as toluene, anisole or 2,4- dimethoxybenzene to the corresponding aldehydes. The formylating ability of systems from 4 and superacids, such as FSO3H, FSO3H/SbF5, C4F9SO3H, and mixtures of aluminum chloride with C4F9SO3H and chlorosulfonic acid, respectively, is compared. In general, low reaction temperatures (−20 to −10 °C) are necessary to obtain aldehydes with acceptable to good yields. Remarkably, at higher temperatures (~ 100 °C) compound 4 can also act as a formylating agent in the presence of suitable zeolites, as e. g. zeolite HBEA. Reaction mechanisms of the new formylation reactions are proposed.
Orthoamide, LXV [1]. Kondensationsreaktionen von Amidinen, Guanidinen, Hydrazin und Hydrazin-Derivaten mit Orthoamiden von Alkincarbonsäuren / Orthoamides,LXV [1]. Condensation Reactions of Amidines, Guanidines, Hydrazine and Hydrazine Derivatives with Orthoamides of Alkyne Carboxylic Acids
Authors: Kantlehner Willi , Mezger Jochen , Stieglitz Rüdiger , Edelmann Kai , Lehmann Hansjörg , Vettel Markus , Kreß Ralf , Frey Wolfgang , Ladendorf Sebastian
Published: February 2015

The orthoamide derivatives 4 react with amidines 10 and guanidines 11 to give 4-dimethylaminopyrimidines 12. The 3-dimethylamino-pyrazoles 13a - c can be prepared from orthoamides 4 and hydrazine. The hydrazine derivative 14, whose constitution was established by crystal structure analysis, is obtained in low yield when hydrazine is added dropwise to a boiling solution of 4d in THF.

Methyl- and phenylhydrazine, undergo reaction with the orthoamides 4a, c yielding mixtures of the isomeric pyrazoles 19 and 20. The reaction of 4c with acylhydrazines 21a - e affords the pyrazole 13b. The pyrazole 26 is produced in the reaction of 4a and acet-hydrazide according to this scheme, whereas 4a reacts with aromatic acid hydrazides 21c - e to give condensation products, which are presumably amidrazones 28. The 4,5-diaza-octatetraene derivative 30 results from the reaction of 4c with p-toluenesulfonylhydrazide. Ketene aminals 34a - c are the products of the reaction of the orthoamides 4b - d with 4,4-dimethylthiosemicarbazide 34, which cyclize on heating to give highmelting pyrazolethiones 35a - c. According to the crystal structure analysis of 35c the compounds have zwitterionic character and are associated via hydrogen bridges in the solid state.
Four Additional Meroterpenes Produced by Penicillium sp Found in Association with Melia azedarach. Possible Biosynthetic Intermediates to Austin
Authors: Fill Taicia Pacheco , Pereira Grace Kelli , Santos Regina M. Geris dos , Rodrigues-Fo Edson
Published: February 2015

Four additional meroterpenes were isolated and identified from rice cultures of Penicillium sp, a fungus obtained from the root bark of Melia azedarach. These new compounds were named preaustinoid B2 (1), preaustinoid A3 (2), austinolide (3), and isoaustinone (4) in analogy with the formerly described compounds. The structures were identified by extensive spectroscopic studies, including 1 D and 2 D NMR spectroscopy and HRMS. Compounds 1 - 4 are probably biosynthetic intermediates to Austin.
3,4-, 4,7- und 1,4,7-substituierte Indenyl-TiCl3-Komplexe: Synthese und vergleichende Diskussion der Substituenteneinflüsse / 3,4-, 4,7- and 1,4,7-Substituted Indenyl-TiCl3 Complexes: Synthesis and Comparison of Substituent Effects
Authors: Weiß Thomas , Meichel Eduard , Sachse Helga , Spange Stefan , Lang Heinrich
Published: February 2015

Me3Si-substituted indenes of type 1-SiMe3-3,4-(CH2)3C9H5 (9), 1-SiMe3-4-R-7-R′C9H5 (11a, R = R′ = Me; 11b, R = R′ = Ph; 11c, R = Me, R′′ = Ph) and 1,1′ -(SiMe3)2-4,7-Me2C9H4 (12) were synthesised as precursors for piano-stool type halfsandwich indenyl-titanium trichloride complexes.Treatment of 9, 11, and 12 with equimolar amounts of TiCl4 gives the complexes (η5-3,4-(CH2)3C9H5)TiCl3 (13), (η5-4-R-7-R′C9H5)TiCl3 (14a, R =R′ = Me; 14b, R =R′= Ph; 14c, R = Me, R′ = Ph), and (η5-1-SiMe3-4,7-Me2C9H4)TiCl3 (15), respectively, with liberation of Me3SiCl.Detailed UV/vis spectroscopic and cyclic voltammetric studies were carried out which allow a comparison of substituent effects in 13 - 15.
Organometallic Compounds of the Lanthanides 182 [1]. Calcium and Neodymium Complexes Containing the dpp-BIAN Ligand System: Synthesis and Molecular Structure of [(dpp-BIAN)CaI(THF)2]2 and [(dpp-BIAN)NdCl(THF)2]2
Authors: Schumann Herbert , Hummert Markus , Lukoyanov Anton N. , Chudakova Valentina A. , Fedushkin Igor L.
Published: February 2015

Oxydation of (dpp-BIAN)Ca(THF)4 with 0.5 equiv. of I2 in THF yields [(dpp-BIAN)CaI(THF)2]2 (1). A corresponding neodymium compound [(dpp-BIAN)NdCl(THF)2]2 (2) has been obtained by reaction of (dpp-BIAN)Na2 with NdCl3 in THF. The X-ray single crystal structure analyses show 1 and 2 to be isostructural dimers containing octahedrally coordinated metal atoms bridged by the respective halides. The chelating dpp-BIAN ligand acts as a radical anion in the Ca2+ complex 1 and as a dianion in the Nd3+ complex 2, respectively.
Triethylborane: An “Old” Reagent with New Functions. 1,2-Hydroboration
Authors: Wrackmeyer Bernd , Khan Ezzat , Bayer Stefan , Shahid Khadija
Published: February 2015

In contrast with previous findings, triethylborane, BEt3, can act as a hydroborating reagent. Thus, the reactions of BEt3 with alkyn-1-yl(trichloro)silanes, di(alkyn-1-yl)dichlorosilanes, alkyn- 1-yl(dichloro)vinylsilanes, trichloro(vinyl)silane, and dichloro(methyl)vinylsilane for several days in excess BEt3 as the solvent at 100 - 120 °C were found to give exclusively products of 1,2- hydroboration. This unexpected behaviour was compared with that of tri-n-propylborane, BnPr3, and 9-borabicyclo[3.3.1]nonane, 9-BBN in analogous reactions, 9-BBN being a well established hydroborating reagent. All products were characterised by a consistent set of NMR data (1H, 11B, 13C and 29Si NMR).