bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and Chiroptical Properties of Some N-(2-Chloro-7-cyclopropyl-4,7-dihydro-4-oxo-thieno[2,3-b]pyridine-5-carbonyl) L-α-Amino Esters
Authors: El-Abadelah Mustafa M. , Nazer Musa Z. , Sabri Salim S. , Khalil Salim M. , Voelter Wolfgang , Geiger Marcela
Published: February 2015

A series of N-(2-chloro-7-cyclopropyl-4,7-dihydro-4-oxothieno[2,3-b]pyridine-5-carbonyl)-L-α-amino esters (5 ) have been prepared via the respective thieno[2,3-b]pyridinyl-5-carbonyl chloride (4). The CD spectra of the L-aliphatic (5a -d ) and L-aromatic (5e-g) a-amino acid derivatives display, in organic solvents, sign inversion of the measured Cotton effect (CE) bands. This chiroptical behaviour is probably associated with differences in conformational isomerism of either set. MS and NMR spectral data of the title compounds are presented.
Synthese, Kristallstrukturen und thermisches Verhalten von (trienH2)[Mn(H2O)3X 3]X . H2O (X=Cl,Br) / Synthesis, Crystal Structures and Thermal Behavior of (trienH2)[Mn(H2O)3X3]X . H2O (X=Cl,Br)
Authors: Feist Michael , Trojanov Sergej , Stiewe Anja , Kemnitz Erhard , Kunze Ralf
Published: February 2015

The compounds (trienH2)[Mn(H2O)3X3]X · H2O(X = Cl,Br) crystallize at room temperature from equimolar solutions of triethylenediamine and MnX2 · 4 H2O in 3M HX in the orthorhombic space group P212121 with a =6.828( 1), b = 12.128(2), c = 18.367(4) Å, Z = 4 for the chloride, and a = 7.001 (1), b = 12.651 (3), c = 18.885(4) Å, Z = 4 for the bromide, respectively. Both structures contain cations (trienH2)2+, complex octahedral anions [Mn(H2O)3X3]- , isolated halide ions and water molecules. The thermal behavior has been investigated on the basis of conventional thermoanalytical as well as TG-MS techniques. The thermal decomposition proceeeds in three stages, i.e. the dehydration forming (trienH2)[MnX4], a phase transition of the tetrahalomanganates(II), and, finally, their decomposition which is influenced by the nature of the atmosphere. The dehydration step is reversible.
Templat-Reaktionen von 3,5-Diphenyl-1,2-dithioliumchlorid mit (Thio)Benzoylhydrazin sowie Nickel- und Zinkacetat / Template Reactions of 3.5 - Diphenyl- 1.2-dithiolium Chloride with (Thio)Benzoylhydrazine and Nickel or Zinc Acetate
Authors: Sawusch Stefan , Schilde Uwe , Uhlemann Erhard , Wellerb Frank
Published: February 2015

The reaction of 3.5-diphenyl-1.2-dithiolium chloride with (thio)benzoylhydrazine in the presence of nickel acetate gives bis(thiodibenzoylmethanato)nickel(II). In the presence of zinc acetate 3.5-diphenyl-2-benzoylimino-isothiazole is received instead of the expected metal chelate. Structural data: Bis(thiodibenzoylmethanato)nickel(II), a = 954,9(1); b = 993,5(1); c = 1488,3(1) pm; α = 83,003(4)°; β = 80,541(5)°; γ = 64,011(5)°; space group Pl̅, Z = 2; 3.5-Diphenyl-2-benzoylimino-isothiazole: a = 976,9(1) b = 846,3(2); c = 2126,9(5) pm; β = 93,24(5)°; space group P 21/c; Z = 4.
Synthese, Struktur- und EPR-Untersuchungen an Bis(tetraphenylphosphonium)- bis(1,2-dithioquadratato)oxovanadat(IV), (Ph4P)2[VO(dtsq)2]/Synthesis, Structural and EPR Investigations on Bis(tetraphenylphosphonium)- bis(1,2-dithiosquarato)oxovanadate(IV), (Ph4P)2 [VO(dtsq)2]
Authors: Wenzel Barbara , Strauch Peter
Published: February 2015

The molecular structure and EPR studies of bis(tetraphenylphosphonium)bis( 1,2- dithiosquarato)oxovanadate(IV) are reported. (Ph4P)2[VO(dtsq)2] crystallizes in the monoclinic space group P21/n with the unit cell parameters a = 10,9820(2), b = 15,4620(3), c = 14,5050(3) Å, β = 95,700(8)°, Z = 2. The g and hyperfine coupling tensors Av obtained from the EPR spectra in liquid and frozen solution are used to characterize the properties of the molecular orbital containing the unpaired electron and are compared to those obtained from EHT-MO calculations.
Reaktionen von Isochinolinium-Salzen mit Hydroxylamin-Derivaten, 1. Mitteilung. N-(Nitrophenyl)-substituierte Verbindungen/Reactions of Isoquinolinium Salts with Hydroxylamine Derivatives, 1st Communication. N-(Nitrophenyl) Substituted Compounds
Authors: Möhrle H. , Nießen R.
Published: February 2015

N-(Nitrophenyl) substituted isoquinolinium salts reacted with nucleophiles of the hydroxylamine type to different products depending on the electron withdrawing strength of the substituent. Mononitro compound 8 produced only the cyclic hydroxylamine 9a, the trinitroderivative 5 solely the ring cleaved oximes. The dinitro substance 1 held an intermediate position and gave rise to a labile cyclic hydroxylamine and a more stable ring opened Z-enamine; hydroxylamine ethers generated cyclic products which showed in dimethylsulfoxide ring chain isomerism with the tautomers.
Metallkomplexe mit biologisch wichtigen Liganden, CXV. Addition von α-Aminosäureestern an [CpFe(CO)3]+: Carbamoylkomplexe Cp(OC)2Fe-C(O)NHCHRCO2R’ und Kristallstruktur von Cp(OC)2Fe-C(O)NHCH2CO2Et / Metal Complexes of Biologically Important Ligands, CXV. Addition of α-Amino Acid Esters to [CpFe(CO)3]+: Carbamoyl Complexes Cp(OC)2Fe-C(O)NHCHRCO2R' and Crystal Structure of Cp(OC)2Fe-C(O)NHCH2CO2Et
Authors: Urban Reinhold , Polbom Kurt , Beck Wolfgang
Published: February 2015

α-Amino acid esters can be added to a carbonyl ligand of [CpFe(CO)3]+CF3SO3
- to give the carbamoyl complexes Cp(OC)2Fe-C(O)NHCHRCO2R′ (R = H, Me, CHMe2, CH2Ph; R′ = Et, Me). This type of reaction may be useful for the marking of peptides at the amino end. The crystal structure of Cp(OC)2Fe-C(O)NHCH2CO2Et was determined by X-ray diffraction.
2.2..5.5,-Tetra-tert-butyl-3,3’-bis(trimethylsilyl)-1,1’-diazacobaltocen / 2.2..5.5,-Tetra-tert-butyl-3,3’-bis(trimethylsilyl)-1,1’-diazacobaltocene
Authors: Kuhn Norbert , Stubenrauch Stefan , Bläser Dieter , Boesec Roland
Published: February 2015

The 1,1′diazacobaltocene pyr2Co (3) is obtained from the reaction of 2,5-di-tert-butyl-3-trimethylsilylpyrrole (pyrH, 2) and CoCl2. The X-ray structure is reported.
Structure of Tl(18-crown-6){Cl3CC(O)N P(O)(OCH3)2}: Coordination of the Ionic Multidentate Weakens the Interaction of the Metal Atom with the Crown Ether
Authors: Trush Victor A. , Domasevitch Konstantin V. , Amirkhanov Vladimir M. , Sieler Joachim
Published: February 2015

The thallium(I) dimethyl-N-trichloroacetylamidophosphate complex with a 18-crown-6 of the composition Tl(18-crown-6){L} (L = {Cl3CC(O)NP(O)(OCH3)2} -) has been prepared and characterized by means of IR spectroscopy and X-ray diffraction (orthorhombic, space group P212121 with a = 8.660( 1), b = 11.557(2), c =26.296(3) Å, Z = 4, V = 2631.8(6) Å3; R1 = 0.0285 and wR2 = 0.0558 for 4314 unique reflections). It was shown that (L-) is coordinated to the central atom in a bidentate manner via oxygen atoms of phosphoryl [Tl-O(l) 2.678(4) Å] and carbonyl groups [Tl-O(2) 3.012(6) Å.The Tl( 18-crown-6)+ moiety adopts a typical “sunrise” coordination with the metal atom laying 1.134(2) Å above the mean plane of the oxygen atoms of the macrocycle. This deviation is the highest value of the structurally examined Tl( 18- crown-6 )+ complexes. The Tl-O (etheric) separations are in the range 2.913(4) - 3.198(5) Å (av. 3.030(6) Å).
Wechselwirkungen in Molekülkristallen, 154 [1 - 3]. Wirt/Gast-Einschlußverbindungen von N,N'-Ditosyl-p-phenylendiamin- Derivaten: Die Kristallstrukturen von N,N'-Di(4-nitro-benzosulfuryl)-p- phenylendiamin und seinen Wasserstoffbrücken-Addukten mit Cyclopentanon, Cyclohexanon, Tetrahydrofuran, N,N-Dimethylformamidsowie Pyridin / Interactions in Molecular Crystals, 154 [1 - 3]. Host/Guest-Inclusion Compounds of N,N'-Ditosyl-p-phenylenediamine Derivatives: The Crystal Structures of N,N'-Di(4- nitro-benzosulfuryl)-p-phenylenediamine and its Hydrogen-Bonded Adducts with Cyclopentanone, Cyclohexanone, Tetrahydrofurane, N,N-Dimethylformamide as well as Pyridine
Authors: Bock Hans , Nagel Norbert , Eller Peter
Published: February 2015

Based on preceeding investigations on the crystallization and structures of 13 inclusion compounds with a variety of guest molecules in the host matrix of N,N′-Ditosyl-p-phenylenediamine, the crystal structures of N,N′-Di(4-nitro-benzosulfuryl)-p-phenylenediamine and the five hydrogen bond acceptor molecules cyclopentanone, cyclohexanone, tetrahydrofurane, N,N-dimethylformamide, and pyridine are reported and discussed. In all of the host/guest aggregates formed, the planes of the (4-nitro)phenyl substituents are more strongly twisted out of the p-phenylene plane than in the guest-free host crystal structure, substantiating the importance of optimum conformation of the sulfonamide backbone. The dominant interactions, however, are the hydrogen bonds from the donor host to the acceptor guest, which prevent the usual formation of (sulfonamide···sulfonamide) hydrogen bond motifs in the host lattice. A pecularity is found in the 4:1 stochiometry of the pyridine inclusion compound of N,N′-di(4-nitro-benzosulfuryl)-p-phenylenediamine.
Chemische Reaktionen in Salzschmelzen, XXI. Titan-vermittelte Synthese von Silanen in Chloroaluminat-Schmelzen / Chemical Reactions in Molten Salts, XXI. Titanium Mediated Synthesis of Silanes in Chloroaluminate Melts
Authors: Liesenhoff Hans , Sundermeyer Wolfgang
Published: February 2015

Silanes of technical interest as starting compounds for semiconducting materials or hydrosilylation reactions, (CH3)xSiH4-x (x = 0, 1,2, 3), are obtained by direct hydrogenation of the corresponding chlorosilanes in the presence of various interstitial hydrides of transition metals (preferably of titanium), which are generated in situ in chloroaluminate melts, and aluminum as a halogen acceptor.
A Short and Productive Synthesis of Racemic α-Lipoic Acid
Authors: Balkenhohl Friedhelm , Paust Joachim
Published: February 2015

Racemic α-lipoic acid is synthesized in four steps from the base chemicals vinyl ethyl ether and cyclohexanone. The total yield is 40%.
p-Tolyl(trimethylsilylethynyl)sulfone as Synthon for the Synthesis of Cp(OC)2M-C =CSiMe3 (M ≡ Fe, Ru). Molecular Structure of Cp(OC)2Fe-C ≡ CSiMe3
Authors: Aechter Bernd , Polborn Kurt , Weinrich Volker , Beck Wolfgang
Published: February 2015

The alkynyl complexes Cp(OC)2M-C≡CSiMe3 (M = Fe, Ru) are formed from p -tolylSO2C≡CSiMe3 and [Cp(OC)2M]-Na+. The structure of Cp(OC)2Fe-C≡CSiMe3 was determined by Xray diffraction.
Synthesis and Structural Study of the Thermochromic Compounds Bis(2-amino-4-oxo-6-methylpyrimidinium) Tetrachlorocuprate(II) and Bis(2-amino-4-chloro-6-methylpyrimidinium) Hexachlorodicuprate(II)
Authors: Díaz Isabel , Fernández Vicente , Belsky Vitaly K. , Martínez Jose Luis
Published: February 2015

The compound bis(2-amino-4-oxo-6-methylpyrimidinium) tetrachlorocuprate(II) 1 contains CuCU4
2- square-planar anions, and bis(2-amino-4-chloro-6-methylpyrimidinium) hexachlorodicuprate( II) 2 quasi-planar CU2CI6
2- anions. Both compounds show thermochromic behaviour. This phenomenon has been studied by X-ray crystallography at variable temperature, with the result that no major change is observed in the geometry of the copper atom. Thus it is possible to assume some influence of the hydrogen bonds and o f the different geometries of intermediate states on the color of the compounds due to the modifications provoked in the L→M charge transfer and in the energy o f the metal d-d transitions. Magnetic measurements of the compounds give information on magneto-structural correlations. Compound 1 is ferromagnetic (Tc ≅ 20 K) due to the perpendicular arrangement of the square anions that allows exchange pathways only via Cu-Cl -Cu , H-bonding or cationic n electron interactions. Compound 2 shows a very complicated behavior at low temperature with local antiferromagnetic fluctuations. Crystal data: 1 C10H10N6O2Cl4Cu, triclinic, P1; 393(2) K: α = 11.053(2), b = 11.334(2), c =14.038(3) (Å), α = 95.76(3), β = 101.35(3), γ=90.15(3)(°) ; 293(2) K: a = 11.022(2), b = 11.289(2), c = 14.001(3) (Å), α = 95.86(2), β = 101.34(2), γ=90.09(3)(°) ; 155(2) K: a = 11.008(2), b = 11.231 (2), c = 13.967(3) (A), a = 95.86(2), β = 101.37(2), γ=89.99(2)(°) ; Z = 4. 2 (C5H7N3Cl3Cu)2 , monoclinic, P21/c; 293(2) K: a = 5.998(1), b =18.669(4), c = 9.466(2) (Å), β =100.93(3)(°) ; 150(2) K: a = 5.971(1), b = 18.655(4), c = 9.383(2) (Å), ß =101.64(1)(°);Z=4
Metallkomplexe mit biologisch wichtigen Liganden, CXIX [1]. Ein tetraedrischer Zink-Komplex (L-terf-Leucin)2ZnCl2 mit Carboxylat-koordiniertem L-terf-Leucin in der / Zwitterform Metal Complexes of Biologically Important Ligands, CXIX [1]. A Tetrahedral Zinc Complex (L-terf-Leucine)2ZnCl2 of Carboxylate Coordinated L-terr-Leucine in the Zwitterionic Form
Authors: Hoffmüller Winfried , Polborn Kurt , Beck Wolfgang
Published: February 2015

From an aqueous solution of ZnCl2 and L-terMeucine the complex (L-terr-Leucine)2ZnCl2 · 2 CH3OH with a distorted tetrahedral structure is formed in which, according to an X-ray structure analysis, the zwitterionic form o f the amino acid is coordinated through the carboxylate group
The Structural Chemistry of GoId(I) Quinoline-2-thiolate and Iodide Complexes of Polytertiary Phosphines
Authors: Tzeng Biing-Chiau , Zank Johann , Schier Annette , Schmidbaur Hubert
Published: February 2015

Treatment of (chloro)gold(I) complexes of di- and tetra-tertiary phosphines with equivalent quantities of sodium quinoline-2-thiolate in methanol / dichloromethane affords the corresponding (phosphine)gold(I) quinoline-2-thiolates in high yields. The di- and tetranuclear complexes, respectively, of α, ω-bis(diphenylphosphino)-propane (1), -butane (2) and -pentane (3) and of tris(2-diphenylphosphino-ethyl)phosphine (4) have been obtained as crystalline solids, and the structures of 2 and 4 have been determined by single crystal X-ray diffraction studies. Unexpectedly, the molecules of 2 are loosely aggregated into strings via weak intermolecular gold-sulfur, not via Au ∙∙∙ Au interactions. Compound 4 is a monomeric tetranuclear cluster in the solid state with two intramolecular gold-gold bonds. Bis(2-diphenylphosphino-ethyl)- phenylphosphine (PPP) forms trinuclear complexes with gold(I) chloride, bromide and iodide (5a - c). The iodide complex features a chain structure through intermolecular Au ∙∙∙ Au contacts between the two terminal P-Au-I units. The closest contacts between the chains are determined by Au ∙∙∙ I and I ∙∙∙ I interactions of the central P-Au-I unit.
[Ni(NH3 )6]S04 : Kristallstruktur und Infrarotspektren / [Ni(NH3)6]SO4: Crystal Structure and Infrared Spectra
Authors: Mockenhaupt Christoph , Eßmann Ralf , Lutz Heinz Dieter
Published: February 2015

The crystal structure of [Ni(NH3)6]SO4 has been determined by single-crystal X-ray diffraction (P21/c; Z = 4; a = 705.0(1), b = 1195.2(2), c = 1180.0(2) pm, β = 96.14(3)°; 2271 reflections; R1 = 3.94%). In the hitherto unknown structure type, both the [Ni(NH3)6]2+ and the SO4
2- ions form chains along [100], The six crystallographically different ammine ligands of the distorted [Ni(NH3)6]2+ octahedra are involved in hydrogen bonds to six crystallographically equivalent SO4
2- ions (site symmetry C1). The strength of the hydrogen bonds differs strongly (νOD of matrix isolated NH2D molecules: 2378 - 2494 cm-1 , N ∙∙∙ O distances: 272 - 340 pm). The temperature evolution of the IR bands reveals the decrease of the dynamic orientational disorder of the NH3 molecules with decreasing temperature.
Condensed [Ru4Sn6] Units in the Stannides LnRu4Sn6 (Ln = La, Pr, Nd, Sm, Gd) - Synthesis, Structure, and Chemical Bonding
Authors: Zumdick Markus F. , Pöttgen Rainer
Published: February 2015

The stannides LnRu4Sn6 (Ln = La, Pr, Nd, Sm, Gd) were prepared by reaction of the elements in an arc-melting furnace and subsequent annealing at 1120 K. The praseodymium, the neodymium, and the samarium stannide were obtained for the first time. The LnRu4Sn6 stannides were investigated by X-ray diffraction both on powders and single crystals. They adopt the YRu4Sn6 type structure which was refined from single crystal X-ray data for the samarium and the gadolinium compound: I4̄2m, a = 686.1 (1), c = 977.7(2) pm, wR2 = 0.0649, 483 F2 values for SmRu4Sn6, and a = 685.2(1), c = 977.6(3) pm, wR2 = 0.0629, 554 F2 values for GdRu4Sn6 with 19 variables for each refinement. The striking structural motif of these stannides are distorted RuSn6 octahedra with Ru-Sn distances ranging from 257 to 278 pm. Four of such octahedra are condensed via common edges and faces forming [Ru4Sn6] units which are packed in a tetragonal body-centered arrangement. The rare-earth atoms fill the voids between the [Ru4Sn6] units. Based on an extended Hückel calculation, strong bonding interactions were found for the Ru-Sn and the various Sn-Sn contacts.
Antimony as a Donor Atom in Silver Coordination Chemistry: Synthesis, IR Spectra and Structure of the Silver(I) Cyanoximate Complexes with Triphenylstibine and Triphenylphosphine Model Compounds
Authors: Domasevitch Konstantin V. , Petkova Elena G. , Nazarenko Alexander Yu. , Ponomareva Vera V. , Sieler Joachim , Dalley N. Kent , Rusanov Eduard B.
Published: February 2015

Silver(I) cyanoximate complexes Ag{ONC(CN)-R} (R = COPh, {L1}; COC(CH3)3, {L2}; benzothiazol-2-yl, {L3}) with triphenylphosphine and -stibine of compositions Ag(PPh3)n{L} (n = 2, 4) and Ag(SbPh3)n{L} (n = 3 for {L1} and {L2}, n = 2 for {L3}) were synthesized by the reaction of the components in acetonitrile solution and characterized by elemental analyses and IR spectroscopy. The crystal structures of Ag(SbPh3)3{L} (L = {L1} (1), {L2} (2), Ag(SbPh3)2{L3} ∙ CH3CN (3) and Ag(PPh3)2{L1} ∙ CH3CN (4), have been determined by X-ray diffraction. For all the compounds examined the coordination environment of the silver atom has the geometry of a distorted terahedron ([AgP2NO] (4); [AgSb3N] (1), (2); [AgSb2N2] (3)). The bis adducts Ag(EPh3)n{L} adopt molecular structures, in which the organic anions are coordinated in bidentate chelate fashion via the nitroso nitrogen atom and the oxygen (nitrogen for {L3}) atom of the substituent R. In the tris-stibino complexes (Ag-Sb 2.670(4) - 2.7748(8) Å; Sb-Ag-Sb 108.87(4) - 115.00(2)°) the cyanoximates are unidentate ligands and coordinated via the nitroso nitrogen atoms (Ag-N ca. 2.35(1) Å). The different behaviour of N ,O and N,N chelating cyanoximes under the same conditions suggests, that the Sb donor triphenylstibine is able to substitute the oxygen atoms in the silver(I) coordination sphere, but not the nitrogen ones. This causes the formation of 1:3 adducts of Ag{L} with SbPh3 for N ,O donors {L1} and {L2}, and only 1:2 for N,N donor anionic {L3}.
Electronic Structure of 2,6-Bis{.N-(2-hydroxyphenyl)immoinethyl}-4-methylphenol
Authors: Hasegawa Miki , Yamada Yasunori , Kumagai Ken-ichi , Hoshi Toshihiko
Published: February 2015

The electronic and molecular structure of 2,6-bis{N-(2-hydroxyphenyl)iminomethyl}-4- methylphenol (hpimp) is clarified from the measurements of electronic absorption and 1H NMR spectra in various solvents and an X-ray diffraction analysis, together with MO calculations. Electronic absorption bands of hpimp are at 422, 397.9, 359, 341, 294.3, 265.8, and 224 nm in the non-polar solvent cyclohexane. In polar solvents, such as methanol, an additional band which is assigned to a partly formed keto-amine hpimp, is observed at 499 nm. From the 1H NMR spectra it is seen that hpimp exists in the enol-imine form in non-polar solvents, and as an equilibrium mixture of enol-imine and keto-amine forms in polar solvents. Each electronic absorption band of solid hpimp in a KBr disk is broadened compared with the solution state, and an additional band, again assigned to the keto-amine form, appears around 499 nm. An X-ray diffraction analysis shows that hpimp assumes a keto-amine structure in the solid state, and forms a column structure along the c-axis. MO calculations suggest that the enol-imine hpimp has a twist structure around the two C−C single bonds, the twist angle being 100° to 120°.
Neue Tetraaminophosphonium-Salze durch Anionenaustausch in flüssigem Ammoniak
Authors: Landskron Kai , Horstmann Stefan , Schnick Wolfgang
Published: February 2015

[P(NH2)4]Br and [P(NH2)4][NO3] have been prepared by anion exchange in liquid ammonia. Single crystals of [P(NH2)4]Br were obtained from an acetonitrile solution in a temperature gradient between 60 °C and room temperature while attempts to grow single crystals of [P(NH2)4][NO3] yielded [P(NH2)4][NO3](OP(NH2)3). Both crystal structures were determined by single crystal X-ray methods at room temperature ([P(NH2)4]Br: P4/nbm, a = 809.2(1), c = 468.1(1) pm, Z = 2, R1 = 0.042, wR2 = 0.077; [P(NH2)4][NO3](OP(NH2)3): Pna21, Z = 4, a = 1023.4(1), b = 1704.7(1), c = 618.0(1) pm, R1 =0.025, wR2 = 0.067. In the solid [P(NH2)4]Br forms a tetragonally distorted variant of the CsCl type of structure. [P(NH2)4][NO3](OP(NH2)3) consists of [P(NH2)4]+cations, [NO3]- anions, and OP(NH2)3 molecules which are interconnected by a complex system of hydrogen bonds.
β-Diketonates and their Analogs: Stabilization of the Dimeric M2{L}4(D)2 (M = Co, Ni) Core in the Complexes with Dimethyl-N-trichloroacetylamidophosphate {Cl3C(O)NP(O)(OCH3)2}-
Authors: Bundya Elizaveta A. , Amirkhanov Vladimir M. , Ovchynnikov Vladimir A. , Trush Victor A. , Domasevitch Konstantin V. , Sieler Joachim , Skopenko Victor V.
Published: February 2015

The coordination compounds of general formula [M{X}2(2-propanol)]2 (M = Co(II) (1), Ni(II) (2); {X} = Cl3CC(O)NP(O)(OCH3)2) have been prepared and characterized by means of IR, UV-VIS spectroscopy and X-ray analysis. The compounds are isomorphous according to X-ray powder diffraction studies. Crystal data for 1: triclinic, P1̄, with a = 9.510(2), b = 12.053(2), c = 23.594(5) Å ,a = 84.74(3), b = 86.47(3), g = 75.45(3)°, Z = 2, V = 2604.7(9) Å3, R1 = 0.067, wR2 = 0.143 for 6299 unique reflection used). The complex adopts a dimeric centrosymmetric molecular array with Co-O-Co bridges formed via the oxygen atoms of phosphoryl groups. This structure is stabilized by intradimeric hydrogen bonds of the type P = O---H with the coordinated 2-propanol. The metal atoms are coordinated in slightly distorted octahedra (Co-O 2.050(5)-2.140(5) Å). Unlike the β-diketonate compounds of similar structure, the dimeric complexes are stable towards donor species and in 2-propanol solution.
Chiral Pool Synthesis of 4a-Substituted Carbocyclic Cyclopentanoid Nucleoside Precursors, I
Authors: Csuk René , Dörr Petra , Kühn Martin , Krieger Claus , Antipin Mikhael Y.
Published: February 2015

A suitable protected D-ribono-1,4-lactone derivative has been used for the straightforward chiral pool synthesis of cyclopentanoid nucleoside precursors. Thus, epoxidation followed by deoxygenation or regioselective ring opening led to nucleoside precursors modified at the positions C(4), C(4a) and C(4,4a) as well as side-chain modified derivatives. The structures of the key intermediates were determined by X-ray analyses.
Formation of η1-P-(2-Phosphinophenol)Ni(0)(PMe3)3 and Oxidation to cis/trans-Bis(2-phosphinophenolato)nickel(II) Complexes
Authors: Heinicke Joachim , Dal Attila , Klein Hans-Friedrich , Hetche Olaf , Flörke Ulrich , Haupt Hans-Jürgen
Published: February 2015

o-Phosphinophenols 1 (P⌒OH ) react with equimolar amounts of Ni(PMe3)4 at low temperatures to give yellow Ni(0) complexes such as [(HO∼P)Ni(PMe3)3] 2a with only P coordination of the P⌒OH ligand. Oxidation of solutions of 1 and Ni(PMe3)4 by dioxygen leads to brown bis(o-phosphinophenolato-P⌒O)nickel chelate complexes 3a-d. Structure elucidation by NMR is consistent with a cis-square planar geometry for 3a-c and a trans-square planar solution structure of the tert-butylphenylphosphino derivative 3d. The geometric isomers were distinguished by different ranges of phosphorus coordination shifts and 31P-13C-2 and 31P-13C-1 coupling constants. In the solid state, 3d adopts also a cis-square planar geometry. The steric stress of the substituents causes anti-orientation of the tert-butyl groups at phosphorus (R,R and S,S diastereoisomers) and a significant distorsion (22°) of the planes of the two five-membered rings. With less bulky substituents the R,S and S,R diastereoisomers are preferred as in the cis-square planar complex 3c with syn-orientation of the two isopropyl and phenyl groups, respectively.
The Intermetallic Compounds GdRe2Al10 and TbRe2Al10, Crystallizing with a Stacking Variant of the YbFe2Al10 Type Structure
Authors: Fehrmann Birgit , Jeitschko Wolfgang
Published: February 2015

The new compounds GdRe2Al10 and TbRe2Al10 were obtained in well-crystallized form by reaction of the elemental components with an excess of aluminum after dissolving the matrix in hydrochloric acid. They crystallize with a new structure type which has been determined for TbRe2Al10 from single-crystal X-ray data: Cmcm, a = 932.2(1), b = 1030.4(1 ), c = 1803.2(3)pm, Z = 8, R = 0.031 for 1159 structure factors and 77 variable parameters. Of the two terbium sites, one does not have full occupancy with terbium, however, it may have mixed Tb/Al occupancy. The resulting compositions are Tb0.948(5)Re2Al10 or Tb0.936(3)Re2Al10.064(3), respectively. The terbium atoms are coordinated by 4 Re and 16 Al atoms. The rhenium atoms are situated in distorted icosahedra formed by 2 Tb and 10 Al atoms. The nine different aluminum atoms have between 12 and 14 neighbors (1 or 2 Tb, 2 Re, and between 8 and 11 Al atoms). The structure may be viewed as consisting of two kinds of alternating layers. One of these is puckered, hexagonal close packed, with a mesh content of 4ReAl3; the other is planar and less densely packed. It has the mesh content 2TbAl4. The same kinds of atomic layers have been found in the structures of YbFe2Al10 and LuRe2Al10. Thus, the three structure types may be considered as stacking variants of each other. The tetragonal CaCr2Al10 (ordered ThMn12) type structure also belongs to this structural family, although the CaAl4 layers somewhat differ from the layers TbAl4, YbAl4, and LuAl4.
Metallkomplexe mit biologisch wichtigen Liganden, CXXIV [1]. NMR-spektroskopische Bestimmung des Enantiomerenverhältnisses von α-Aminosäuren mit Hilfe eines chiralen orthometallierten Palladiumkomplexes/Metal Complexes of Biologically Important Ligands, CXXIV [1]. NMR-Spectroscopic Determination of the Enantiomeric Ratio of α-Amino Acidsby Use of a Chiral Orthometallated Palladium Complex
Authors: Böhm Andreas , Hauck Thomas , Beck Wolfgang
Published: February 2015

The chiral orthometallated palladium complex (S)-[Pd{C6H4 (CH(CH3)N(CH3)2 )-C,N}Cl]2 (1) can be used as a reagent for the determination of the enantiomeric ratio of α-amino acids. By reaction of 1 with mixtures of several D- and L-α-amino carboxylates diastereoisomers of the α-amino acidato complexes 2a - g are obtained. 1NMR determination of the ratio of the diastereoisomers provides the D/L-ratio of the used D- and L-α-amino carboxylates and is therefore a simple method for the determination of the enantiomeric ratio of α-amino acids.
Polysulfonylamine, CXVII Wasserstoffbrücken in kristallinen Onium-dimesylamiden: Sechs systematisch variierte sek.-Ammonium-dimesylamide mit sechs verschiedenen null-, ein-oder zweidimensionalen Wasserstoffbrückenmustern/ Polysulfonylamines, CXVII Hydrogen Bonding in Crystalline Onium Dimesylamides: Six Systematically Varied sec. - Ammonium Dimesylamides Exhibiting Six Different Zero-, One-, or Two-Dimensional Hydrogen Bonding Patterns
Authors: Moers Oliver , Wijaya Karna , Henschel Dagmar , Blaschette Armand , Jones Peter G.
Published: February 2015

In order to examine packing preferences and hydrogen bond patterns in secondary ammonium salts, low-temperature X-ray analyses were conducted for six compounds of general formula R2NH2
+MeSO2)2 N-, where R2NH2
+ = Me2NH2
+ (1, triclinic, space group P1̄̄), MeEtNH2
+,(2, monoclinic, P21/c), Et2NH2
+ (3. triclinic, P1), pyrrolidinium (4, triclinic, P1), piperidinium (5, monoclinic, C2/c) or morpholinium (6, monoclinic, P21/c). Throughout the series, the constant anion retains a rigid conformation approximating to C2 symmetry and thus provides a geometrically reliable set of five potential hydrogen bond acceptors. Nevertheless, the six compounds exhibit a variety of unpredictable packing patterns, showing that, in unfavourable cases, the steric demands of molecular fragments not involved in hydrogen bonding can substantially alter the structure of a family of ionic crystals. In the present structures, the NH2
+ donor groups form hydrogen bonds N+-H···N-/O to two (3-6) or three (1,2) adjacent anions. The occurrence of various two-, three- and four-centre hydrogen bonds leads to six different patterns, resulting in cation-anion layers (1, 2), discrete formula unit dimers (3, 4) or cation-anion chains (5, 6); in the morpholinium salt 6, these chains are associated into layers by a weak N+ - H ··· O(cation) interaction. In each of the crystal packings, short C-H···O contacts with H···O ≤ 270 pm and C-H ···O ≥ 130° are observed.
Polysulfonylamine, CXVIII Wasserstoffbrücken in kristallinen Onium-dimesylamiden: Drei prim. -Ammonium-dimesylamide mit zwei- oder dreidimensionalen Wasserstoffbrückenmustern/Polysulfonylamines, CXVIII Hydrogen Bonding in Crystalline Onium Dimesylamides: Three prim. -Ammonium Dimesylamides Exhibiting Two- or Three-Dimensional Hydrogen Bond Patterns
Authors: Henschel Dagmar , Moers Oliver , Wijaya Karna , Blaschette Armand , Jones Peter G.
Published: February 2015

In order to study hydrogen bonding patterns in primary ammonium salts and the hydrogen bond acceptor potential of the dimesylamide anion, low-temperature X-ray structures have been determined for the 1:1 salts RNH3
+(MeSO2)2N- , where R = Et (1, monoclinic, space group P21/n, two independent formula units A and B) or 1-adamantyl (2, monoclinic, P21/C) and for the 1:2 salt [H3NCH2CH2NH3]2+ ·2 (MeSO2)2N- (3, monoclinic, P21/n, cation crystallographically centrosymmetric). The NH3
+ donor groups form two-centre or three-centre hydrogen bonds to four (B) or three (A, 2, 3) adjacent anions, giving rise to fundamentally different networks. The crystal packing of 1 displays a three-dimensional system of eight independent H bonds and may be viewed as a commensurate ionic self-clathrate, in which finite (A)2 cyclodimers are inserted as guest entities into parallel tunnels between infinite (B)∞ tapes. In contrast, owing to the steric demands of the 1-adamantyl group, compound 2 merely exhibits a twodimensional pattern constructed from four independent H bonds and leading to cation-anion sheets. In the packing of 3, two crystallographically independent H bonds generate a tape substructure of cations and anions in the ratio 1:2; these tapes are cross-linked into a three-dimensional network via a third independent H bond. In each of the structures, short C -H ··· A contacts (A = N- and/or O) with H ··· A ≤ 260 pm and C - H ··· A ≥ 130° are observed.
Redox Properties of 1,2-Dihydro[60]fullerene Derivatives with Electron-Withdrawing Substituents
Authors: Irngartinger Hermann , Weber Anton
Published: February 2015

The cyclic voltammograms of 1-cyano-2-hydroxy-1,2-dihydrofullerene derivatives indicate a complex redox behavior. The first reduction peak of these new compounds is at less negative values compared to the parent [60]fullerene. This is a consequence of the two electronwithdrawing groups, which are attached directly to the C60 moiety.
Darstellung und spektroskopische Charakterisierung von Natriumpentacyano(phosphan/phosphit)ferraten(III) / Preparation and Spectroscopic Characterization of Sodium Pentacyano(phosphane/phosphite)ferrates(III)
Authors: Inoue Hidenari , Osone Satomi , Fluck Ekkehard
Published: February 2015

Sodium pentacyanoferrates(III) of the type Na2[Fe(CN)5L] (L = phosphane or phosphite) have been prepared from sodium pentacyanoferrates(II), Na3[Fe(CN)5L], by bromine oxidation and characterized by Mössbauer, IR, and electronic spectroscopy. Isomer shifts and quadrupole splittings lie within the range commonly found in low-spin iron(III) complexes. A linear correlation was found between isomer shifts and CN stretching and Fe-CN bending frequencies, respectively. The spectroscopic parameters show that the dπ-dπ back bonding of the Fe-P bonds is synergetically strengthened with increasing σ donor capability of the phosphorus ligands.
New Information on the Na-Ti-Se Ternary System
Authors: Aitken Jennifer A. , Kanatzidis Mercouri G.
Published: February 2015

Molten Salt Fluxes, Polychalcogenide, Polyselenide Na2Ti2Se9 was first discovered in the quaternary system Na/Ti/P/Se, but it can be prepared rationally by dissolving Ti in a Na2Sex flux at 375 °C. The silverish dark red crystals are air-and water-stable. A new method for synthesizing Na4TiSe4 is also reported. Na2Ti2Se9 crystallizes in space group P21, with a = 12.785(4), b = 14.848(4), c = 13.961(4) Å, ß = 94.556(4)°, R1 = 0.0592 and wR2 = 0.1336. The structure is similar to that of KsNaTi6Se27. It contains infinite one dimensional chains which run parallel to the c-axis and contain Ti4+ centers bonded to Se2
2- and Se2- species. The l/∞[Ti2(Se2)4Se]2- chains pack together in a hexagonal pattern. All of the titanium atoms are surrounded by a pentagonal bipyramid of selenium atoms. The selenium atoms bridge the Ti centers in two different ways. Na2Ti2Se9 is a semiconductor with a band gap, Eg, of ~ 1.02 eV. The Raman spectra are also reported.
Metallkomplexe mit biologisch wichtigen Liganden, CXXXII*. N,O-Chelatkomplexe von Palladium(II), Platin(II) und Iridium(III) mit dem Anion von Glucosaminsäure (2-Amino-2-deoxy-D-gluconsäure) / Metal Complexes of Biologically Important Ligands, CXXXII*. N ,O -Chelate Complexes of Palladium (II), Platinum (II), and Iridium (III) with the Anion of Glucosaminic Acid (2-Amino-2-deoxy-D-gluconic Acid)
Authors: Krawielitzki Stefan , Beck Wolfgang
Published: February 2015

From 2-amino-2-deoxy-D-gluconic acid (LH) and chloro bridged metal complexes the N,O chelates (R3P)(Cl)Pd(L) (R = n-C4H9, Ph), (n-C4H9)3P(Cl)Pt(L), (C6H4CH2NMe2)Pd(L), (Ph-N=N-C6H4)Pd(L), Cp*(Cl)Ir(L) are formed. They were characterized by analytical and spectroscopic data.
Synthese und Struktur von benzylsubstituierten Derivaten des Dinickel-Tripeldeckerkomplexes μ-η5,η5(2,3–Dihydro–1,3-diborolyl)-(η3–allyl)(η4–1,5–hexadien) dinickel / Synthesis and Structure of Benzyl Substituted Derivatives of the Dinickel Triple-Decker Complex μ–η5, η5–(2 ,3–Dihydro–1,3 -diborolyl)– (η3–allyl)(η4– 1,5 -hexadiene)dinickel
Authors: Siebert Walter , Huck Stefan , Pritzkow Hans
Published: February 2015

Hydroboration of phenyl- and mesitylethyne with in situ formed HBCl2 leads to an isomeric mixture of 1,1-bis(dichloroboryl)-2-phenylethane (4a) and l,l-bis(dichloroboryl)-1-phenylethane (4b) (ratio 3 : 1) and regioselectively to 1,1-bis(dichloroboryl)-2-mesitylethane (4c). Treatment of 4a/b and 4c with BI3 gives the corresponding tetraiodo compounds 5, which undergo redox reactions with butyne-2 to form the 1,3-diiodo-4,5-dimethyl-2,3-dihydro-1,3- diborole derivatives 6a/b and 6c. Reactions of the diiodo-1,3-diboroles with AlMe3 or LiMe result in the formation of the very air-sensitive pentaorganyl-1,3-diboroles 1a, 1c and the hexaorganyl-1,3-diborole 1b.

The mixture of 1a/b as well as 1c react with bis(η3-allyl)nickel to give black products, which are chromatographed on silica with hexane as eluent. The brown solids were recrystallized from pentane to give the light-brown crystals of μ-η5,η5-[2-benzyl-l,3 ,4 ,5 -tetramethyl-2 ,3-dihydrol, 3-diborolyl](η3-allyl)(η4-1,5-hexadiene)dinickel (2a, 34%) and μ-η5,η5-[2-(2 ,4 ,6-trimethylbenzyl)- 1,3 ,4 ,5-tetramethyl-2 ,3-dihydro-1,3-diborolyl](η3-allyl)(η4-1,5-hexadiene)dinickel (2c, 43%). lb does not react with Ni(C3H5)2 to form any tripledecker. The compositions of the new compounds follow from spectroscopic and analytical data, and from X-ray structure analyses of 6a and of 2a. The structure of the η4-1,5-hexadiene-η3-allyl-dinickel triple-decker 2a finally disproved the alternative tris(allyl)dinickel arrangement.
Zur Acylierung von 2,3-Dihydro-l,3-diisopropyl-4,5- dimethylimidazol-2-yliden [1] / Acylation o f 2,3-Dihydro-l,3-diisopropyl-4,5-dimethylimidazol-2-ylidene [1]
Authors: Kuhn Norbert , Steimann Manfred , Walker Michael
Published: February 2015

Acylation, Heterocycles, Imidazoles 2,3-Dihydro-l,3-diisopropyl-4,5-dimethylimidazol-2-ylidene (2, Im) reacts with PhC(O)X to give the imidazolium salts [PhC(O)Im]F (3) and [PhC(O)Im]Cl (5). From 3 and the corre­ sponding fluoro compounds, the salts [PhC(O)Im][BF4] (4a), [PhC(O)Im][Ph3SiF2] (4b) and [PhC(O)Im] [Ph3SnF2] (4c) are obtained. 2 reacts with oxalylic chloride under CO elimination to give the salt [Im2CO]Cl2 (7). The X-ray data of 4c and 7 · 4 H20 · 2 HCl ([Im2CO][Cl4H10O4]) are reported.
Mono-and Bis(cyclopentadienyl)hafnium(IV) Derivatives with Higher Fatty Acids
Authors: Pandey O. P. , Sengupta S. K. , Baranwal B. P. , Shukla Saroj K. , Bhatt Alpana
Published: February 2015

The reactions of Cp2HfCl2 with some higher monocarboxylic acids having straight chains, caprylic (C8H16O2), lauric (C12H24O2), myristic (C14H28O2), palmitic (C16H32O2), stearic (C18H36O2), and behenic (C22H44O2) acid, have been studied in anhydrous tetrahydrofuran in 1:1 and 1:2 molar ratios, respectively. The reaction products isolated, of types Cp2Hf(L)Cl, CpHf(L)2Cl (LH represents different carboxylic acids), have been characterised by conductivity and magnetic susceptibility measurements and spectral (infrared, electronic, 1HNMR and 13C NMR) data. The bonding of the carboxylato ligand in these complexes has been discussed and plausible structures have been established.
Darstellung und Kristallstruktur von Cs6Cl4O / Preparation and Crystal Structure of Cs6Cl4O
Authors: Mudring Anja-Verena , Jansen Martin
Published: February 2015

The solid state synthesis and the crystal structure of Cs6Cl4O(Pearson-code hR22, R3c, a = 1324.7(6), c = 1658(1) pm, Z = 6, 931 reflections with Io > 2σ(I), R1 = 0.040, wR2 = 0.114) are reported. The compound crystallises isotypically with Rb6Cl4O in the anti-K4CdCl6 type of structure. The structure consists of infinite chains of alternating face-sharing OCs6 octahedra and ClCs6 trigonal prisms which are separated by chloride anions. The underlying structural concept and the analogy to perovskites are outlined.
Structural Study of a Binuclear Zinc Complex of 2,6-Diacetylpyridine Bis{N(4)-dimethylthiosemicarbazone}, [Zn(2,6Ac4DM)]2 · MeCN
Authors: Labisbal Elena , Castiñeiras Alfonso , Brown Christine A. , West Douglas X.
Published: February 2015

Zinc, 2,6-Diacetylpyridine Bis{N(4)-dimethylthiosemicarbazone}, Electrochemical Synthesis Zinc metal was oxidized in the presence of 2,6-diacetylpyridine bis{N(4)-dimethylthiosemi-carbazone} (2 ,6H2Ac4DM) in an acetonitrile solution, to produce a complex of the formula [Zn(2 ,6Ac4DM)]2-CH3CN. One of the zinc atoms is distorted octahedrally 6-coordinate and the coordination involves both pyridyl nitrogen atoms of the two ligands, the imine nitrogen atom and the thiolato sulfur atom of one thiosemicarbazone moiety of each ligand. The other zinc center is distorted tetrahedrally 4-coordinate with NS coordination of the two remaining thiosemicarbazone moieties. The complex crystallizes in the monoclinic space group C2/c with a = 14.952(2), b = 17.656(3), c = 15.553(4) Å, ß = 111.456(16)°, V= 3821.5(13) Å3 and Z = 4.
Metallkomplexe mit biologisch wichtigen Liganden, CXXXIII [1], a-Aminocarboxylat-Chelate von cyclometallierten Rhodium-Komplexen Metal Complexes of Biologically Important Ligands, CXXXIII [1]. α-Aminocarboxylate Chelates of Cyclometalated Rhodium -Komplexes
Authors: Böhm Andreas , Polbom Kurt , Beck Wolfgang
Published: February 2015

The chloro bridged complexes [(2-phenylpyridine-C,N)2RhCl]2 and [(benzo[h]chinoline-C,N)2RhCl]2 react with the anions of alanine, valine and phenylalanine to give the chiral octahedral N,O-chelates L2Rh(α-aminocarboxylate) (1 -5) as mixtures of two diastereoisomers. The complex (benzo[h]chinoline-C,N)2Rh[(S)-NH2CH(CH3)CO2-N,0] was characterized by X-ray diffraction. Its crystals contain two diastereoisomers in the unit cell.
Modes of Xanthine Complexation to Dirhodium Tetrakis[(R)-α-methoxy-α- (trifluoromethyl)-phenylacetate] in Solution and in the Solid State
Authors: Rockitt Sven , Wartchow Rudolf , Duddeck Helmut , Drabczynska Anna , Kiec-Kononowicz Katarzyna
Published: February 2015

It is show n by IR and NMR studies that the xanthines 1-5 prefer a side-on com plexation to the chiral dirhodium tetrakis[(R)-α-methoxy-α-(trifluoromethyl)phenylacetatel (Rh*) in solution whereas carbonyl groups are involved in the solid state. For 6, at least the carbonyl group C-6 contributes to complexation in solution as well. A lternating strands of 6 and Rh* exist in the solid state as revealed by X-ray diffraction analysis described in detail. The determination of enantiomeric excess of the chiral xanthine 6 can easily be accomplished by the “dirhodium method ” (1H and 13C NMR in the presence of Rh*).
Solvothermal Syntheses, Crystal Structures and Properties of Thiomolybdates with Complex Transition Metal Cations
Authors: Ellermeier Jan , Bensch Wolfgang
Published: February 2015

The new compounds Ni2(tren)3(MO₂O2S6)2 · 2.75 H2O (I) and CO₂(tren)3(MoS4)2 (II) (tren = tris(2-aminoethyl)amine) were prepared under solvothermal conditions. The structure of I is built up of one-dimensional [Ni2(tren)3]n
4+ chains and isolated [MO₂O2S6]2-anions. Each Ni atom in the cationic chain is surrounded by six N-atoms to form a distorted octahedron. The connection of the Ni-atoms in the [Ni2(tren)3]n
4+ -units with the tren molecules leads to zigzag chains in the (100) plane. The situation is different for compound II which consists of isolated [CO₂(tren)3]4+ cations and discrete tetrahedral [MOS4]2-anions. The Co atom in the cation is in a distorted trigonal bipyramidal environment of four N atoms of one tren molecule and of one N atom from a bridging tren-molecule, building up the dimeric structure of the [CO₂(tren)3]4+ unit. Between the anions and cations of both compounds hydrogen bonding is observed. The thermal behaviour of I and II was investigated using differential thermoanalysis and thermogravimetry. On heating I first looses the crystal water and then decomposes slowly in one step, whereas II decomposes also in one step, but at a significantly lower temperature.
Collidinium- und Imidazolium-Salze Fluor-haltiger Anionen. Die Kristallstruktur von [CollH]2 [AsF6][As2 F11] (Coll = 2,4,6-Trimethylpyridin) / Collidinium and Imidazolium Salts of Fluorine-Containing Anions. The Crystal Structure of [CollH]2[AsF6][As2F11] (Coll = 2,4,6-Trimethylpyridine)
Authors: Kuhn Norbert , Fuchs Stefan , Minkwitz Rolf , Berends Thorsten
Published: February 2015

Die Kristall­ struktur von [CollH]2 [AsF6][As2F11] (Coll = 2,4,6-Trimethylpyridin) Collidinium and Imidazolium Salts of Fluorine-Containing Anions. The Crystal Structure of [CollH]2[AsF6][As2F11] (Coll = 2,4,6-Trimethylpyridine) From s-Collidine (1, Coll) and aqueous HF compounds of the composition Coll · n HF (n = 1 -2) are formed which are transformed to [CollH]+ [HF2]- (2) by sublimation. [CollH]2[AsF6][As2F] J (3) is obtained from 1 and the superacid system HF/AsF5. 2 reacts with 2,3-dihydro-l,3-diisopropyl-4,5-dimethylimidazol-2-ylidene (4, Im) to give the imidazo­ lium salt [ImH]+ [HF2]- (5). Hydrogen bonds in the crystal structure of [CollH]2[AsF6][As2Fn ] (3) are discussed.
Synthesis and Bioactivities of Naturally Occurring Anthraquinones: Isochrysophanol, Isozyganein, ω-Hydroxyisochrysophanol and Morindaparvin
Authors: Zaidi Javed H. , Naeem Fazal , Iqbal Rashid , Choudhary Mohammed Iqbal , Khan Khalid Mohammed , Perveen Shahnaz , Shah Syed T. Ali , Hayat Safdar , Voelter Wolfgang
Published: February 2015

Isochrysophanol, isozyganein, ω-hydroxyisochrysophanol, and morindaparvin are naturally occurring substituted anthraquinones. We report the synthesis of these compounds as well as selected biological activities.
Soluble Pyridine Complexes Of The Ternary Gallium(III) Chalcogenide Halides (GaEX)3, With E = S, Se And X = Cl, Br
Authors: Nogai Stefan D. , Schier Annette , Schmidbaur Hubert
Published: February 2015

The four ternary gallium(III) chalcogenide halides GaEX with E = S, Se and X = Cl, Br can be prepared a) from the binary gallium(III) chalcogenides Ga2E3 and halides Ga2X6, b) from gallium(I) tetrahalogallates(III) GafGaX4] and the chalcogen E, and c) from gallium metal and the dichalcogen dihalides E2X2. The new method c) was shown to be the most convenient preparation. The products are readily soluble in pyridine to give trinuclear molecular complexes [GaEX·Py]3 which are not volatile without decomposition, but can be purified by crystallization. The structures have been determined by single crystal X-ray diffraction techniques. The two chlorides are isostructural and show twisted tub-form six-membered ring molecules with the pyridine donors in axial positions. The two bromides are also isostructural, but with the pyridine ligands in two axial and one equatorial positions
Guaianolide Sesquiterpene Lactones From Cichorium Intybus (Asteraceae) [1]
Authors: Deng Yonghong , Scott Lincoln , Swanson Devin , Snyder John K. , Sari Nil , Dogan Hanzade
Published: February 2015

Ten guaianolides, including three previously unreported natural products, were isolated from the aerial parts of Cichorium intybus (Asteraceae), more commonly known as chicory. Two of the new compounds ( 8 and 9) were analogues of lactupicrin and 11/β,13-dihydrolactupicrin, respectively, with the C-15 oxidized to the aldehyde state. The third new natural product, which we have called mtybulide A (10), is an isomer of lactucin with the lactone closed to the C-8 oxygen rather than the C-6
Enaminones as Building Blocks In Heterocyclic Synthesis: A New One Pot Synthesis of Polyfunctional Substituted Pyridines
Authors: Agamy Samia Michel , Abdel-Khalik Mervat Mohammed , Mohamed Mona Hassan , Elnagdi Mohammed Hilmy
Published: February 2015

Enaminones react with a variety of active methyl and methylene reagents in presence of ammonium acetate to yield functionally substituted pyridines in good yields. The reaction proceeded via initial Michael addition across the double bond followed by cyclization. The reaction of enaminone with aromatic aldehyde in acetic acid/ammonium acetate afforded the dihydropyridine that was oxidized to the corresponding pyridine.
Donor-Acceptor Complexes between Simple Phosphines. First Structural Data for an Almost Forgotten Class of Compounds
Authors: Müller Gerhard , Matheus Hans-Joachim , Winkler Martin
Published: February 2015

Lewis acid-base adducts between simple phosphines have been structurally characterized for the first time in the form of (Me3P)PBr3 (1) and (Me3P)PBr2Bz′ (2; Bz′ = 3,5-dimethylbenzyl). On the basis of its solid-state structure the bonding situation in 1 may be described as intermediate between a neutral donor-acceptor complex containing hypervalent phosphorus(III) and an ion pair, according to the resonance formulae Me3P → PBr3 ↔ [Me3 P-PBr2]+Br- . The weak (incomplete) bond formation to the third bromine atom clearly reflects the reluctance of trivalent phosphorus to accommodate more than four electron pairs in its valence shell. (Crystal data for 1: monoclinic P21/n, a = 7.142(3), b = 16.844(2), c = 8.139(4) Å, ß = 106.24(2)°, Z = 4). As a result of the inferior acceptor properties of PBr2Bz′ as compared to PBr3 , 2 has more ion pair character [Me3P-PBrBz′]+Br- than 1. (Crystal data for 2: orthorhombic P 212121, a = 7.063(2), b = 8.578(2), c = 25.158(4) Å, Z = 4). Both compounds have short P-P bonds (1: 2.264(2); 2: 2.236(2) Å). The results are compared with previous IR/Raman and NMR investigations on 1 : 1 and 2 : 1 adducts between organophosphines (as donors) and phosphorus trihalides (as acceptors).
Structural Influence of Hydrogen Bonding and π-Stacking in trans-Diazido-tetrakis( pyrazole)nickel(II) and trans-Diazido-tetrakis(3-methylpyrazoIe)nickel(II)
Authors: Zhang Cungen , Janiak Christoph , Brombacher Horst
Published: February 2015

The molecular nickel complexes trans-diazido-tetrakis(pyrazole)nickel(II) and trans-diazido- tetrakis(3-methylpyrazole)nickel(II) feature terminal monohapto-bound azide ligands. The pyrazole (pyr) ring planes are aligned along the Nazide-Ni-Nazide axis by intramolecular N-H···Nazide bonds. The crystal packing is controlled by π-stacking between both pyrazole rings and azide ligands, N-H···Nazide hydrogen bonds, and intermolecular N-H-πpyr and C-H···N/πazide interactions.