bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation and Crystal Structures of the Ternary Compounds Ag2SiP2 and AuSiP
Authors: Kaiser Peter , Jeitschko Wolfgang
Published: August 2018

The title compounds were prepared by solid state reaction of the elemental components. Their crystal structures were determined from single-crystal X-ray diffractometer data. Ag2SiP2: 14̄2d, a = 652.75(5) pm, c = 855.0(1) pm, Z = 4, R = 0.024 for 611 structure factors and 14 variable parameters; AuSiP: R3m, a = 345.9(1) pm, c = 1720.0(3) pm, Z = 3, R = 0.023 (352 F values, 11 variables). The silicon atoms in Ag2SiP2 are tetrahedrally coordinated by phosphorus atoms. The compound might therefore be considered as a phosphidosilicate and its formula can be rationalized as (Ag+1)2Si+4(P-3)2. However, Ag2SiP2 is not a tetrahedral compound since the phosphorus atoms have five near neighbors (3Ag + 2Si) and the silver atoms are coordinated by three phosphorus atoms in almost trigonal planar coordination. Weak silver-silver bonding is assumed for the shortest Ag-Ag contacts of 318 pm. In AuSiP the gold atoms are in a linear coordination of one silicon (235.5 pm) and one phosphorus atom (232.6 pm). The silicon and phosphorus atoms are tetrahedrally coordinated (3Si + 1 Au and 3P + 1 Au, respectively). Thus, the elements can be assigned oxidation numbers according to the formula Au+1Si+2P-3 . This structure was also refined in the centrosymmetric space group R3̄m, but in this improper setting the silicon and phosphorus atoms occupy one crystallographic site with random occupancy.
Metallkomplexe von Farbstoffen, VIII [1]. Ein- und zweikernige Palladium- und Platin(II)-Chelat-Komplexe mit dem Mono- und Dianion von Indigo und Indigoderivaten / Metal Complexes of Dyes, VIII [1]. Mono- and Dinuclear Palladium and Platinum (II) Chelate Complexes of the Mono- and Dianion of Indigo and Derivatives thereof
Authors: Lenz Andreas , Schmidt Christoph , Lehmann Annette , Wagner Barbara , Beck Wolfgang
Published: August 2018

A series of mono and bis N,O-chelate complexes 1-32 with the mono and dianion of indigo and indigo derivatives (R3P)(C1)M(L-H+) (M = Pd,Pt), (n3-allyl)Pd(L-H+), (Ph2C=NCH2CO2Et-H+)Pd(L-H+), (PhN=NPh-H+)Pd(L-H+), (C5H5)Fe(C5H3CH2NMe2)Pd(L-H+), [(R3P)(Cl)Pt]2(L-2H+), [(n3-allyl)Pd]2(L-2H+), [(C6H4CH2NMe2)Pd]2(L-2H+) with L = indigo, 4,4′-dichloro-, 6,6′-dichloro-, 6,6′-dibromo-, 6,6′-di-nBu-, 4,4′-dichloro-, 5.5′dibromo-, 5,5′, 6,6′-tetramethoxy-, 4.4′-di-S12H25-, 5,5′-di-SO3Na- indigo, indigo malonic ester and tetrahydro indigo have been prepared from chloro bridged metal complexes. In comparison to the free neutral indigo ligands the complexes show a high bathochromic shift in the VIS spectra (150-300 nm) which is mainly due to the anionic character of the coordinated indigo ligands. The structure of [(Et3P)(Cl)Pt]2(indigo-2H+) has been determined by X-ray diffraction.
Röntgenstrukturanalyse von zwei Verbindungen des Kupfertyps BaMLn2O5 (M = Zn, Ln = Sm, Tm) und von BaSmAIZn3O7 / X-Ray Analysis of Two Compounds of the Copper Type BaMLn2O5 (M=Zn, Ln=Sm, Tm) and of BaSmAlZn3O7
Authors: Rabbow Ch. , Panzer S. , Müller-Buschbaum Hk.
Published: August 2018

Kupfertyps BaMLn2O5 (M=Zn, Ln=Sm, Tm) und von BaSmAIZn3O7 X-Ray Analysis of Two Compounds of the Copper Type BaMLn2O5 (M=Zn, Ln=Sm, Tm) and of BaSmAlZn3O7 The barium zinc lanthanoide oxides BaZnSm2O5 (I) and BaZnTm2O5 (II) crystallize in the BaCuLn2O3 copper type with orthorhombic symmetry, space group D16
2h,Pnma, (I)

a = 12.575(2), b = 5.804(1), c = 7.198(1) Å and (II):

a = 12.258(2), b = 5.684(1), c = 7.010(2) Å, Z = 4. Zinc shows square pyramidal oxygen coordina­ tion, but the strong elongation of the CuO5 pyramid in the copper type is missing. BaSmAlZn3O7 crystallizes in the space group C4
6V-P63mc, a = 6.346(1), c = 10.237(3) Å, Z = 2. The metal coordination of oxygen and the shifts of the ratio Al : Zn at the sites (6c) and (2a) depending on the size of the lanthanoid ions are discussed.
Metal-Mediated Assembly of Hexameric Ethylcycloarsoxane (C2H5AsO)6 in Mono-and Dinuclear Complexes with Tetrahedral and Octahedral Coordination Spheres
Authors: Häusler Thomas , Sheldrick William S.
Published: August 2018

A metal-assisted ring expansion from the preferred solution species (EtAsO)n, n = 3,4, to the hexameric ligand (EtAsO)6 is observed for the reactions of [ReBr(CO)5], [RuCL2(Ph3P)3], RhCl3 ·3H2O and [Cu2CF3SO3)2(C6H6)] with ethylcycloarsoxane. Whereas two metal frag­ments are facially coordinated by the upper and lower three As atoms of a flattened As6O6 cuboctahedron in both [{ReBr(CO)2}2 {μ-[cyclo-(EtAsO)6]}] (1) and [Cu2{μ-[cyclo-(EtAsO)6]}(Me2PhP)2](CF3SO3)2 (4), potential ring strain restricts the reaction with the other compounds to the formation of mononuclear complexes [RuCl2{cyvclo-(EtAsO)6}(Ph3P)] (2)and [RhCl3{cyclo-(EtAsO)6}] (3) with k3As1,3,5 coordination. The structures of 1 - 4 were established by X-ray structure analysis. A shift in the ν(As-O) IR absorption bands to higher wavenumbers (830 - 788 cm-1 ) is characteristic for (EtAsO)6 complexes in comparison to those of the cyclic tetramer (781-747 cm-1 ).
Darstellung und Charakterisierung der Carbosilazane Bis[tris(methylamino)silyl]methan und Bis[tris(phenylamino)silyl]methan/Preparation and Characterization of the Carbosilazanes Bis[tris(methylamino)silyl]methane and B is[tris(phenylamino)silyl]m ethane
Authors: Jansen M. , Bzik S.
Published: August 2018

Bis[tris(methylamino)silyl]methane (1) and bis[tris(phenylamino)silyl]methane (2) have been synthesized as potential precursors of porous oxygen-free solids by the reaction of bis(trichlorsilyl)methane with methylamine and with lithiated aniline, respectively. Compound 2 was characterized by a crystal structure analysis. It crystallizes in the monoclinic space group P 21 ,/c with the unit cell parameters a= 10.963(2),b= 17.801(2), c = 17.557(2) Å, β = 97.96(2)° and Z = 4 (R1, = 4,4 %, wR2 = 9,8 %, 5950 independent reflections).
Synthese von Bis[pyridin-phthalocyaninato(1,5-)iridium(II)]iodid und Pyridin-iodo-phthalocyaninato(2-)iridium(III)-Pyridin durch schrittweise Oxydation von Bis[pyridin-phthalocyaninato(2-)iridium(II)]/Synthesis of Bis[pyridine-phthalocyaninato(1,5-)iridium(II)] Iodide and Pyridine-iodo-phthalocyaninato(2-)iridium(III)-Pyridine by Successive Oxidation of Bis[pyridine-phthalocyaninato(2-)iridium(II)]
Authors: Hückstädt Heiner , Homborg Heiner
Published: August 2018

Successive oxidation of bis[pyridine-phthalocyaninato(2-)iridium(II)] with iodine first yields mixed-valent bis[pyridine-phthalocyaninato(1,5-)iridium(II)] iodide ([(Ir(py)pc1.5-}2]I) and then pyridine-iodo-phthalocyaninato(2-)iridium(III)-pyridine ([Ir(py)(I)pc2-]·py). The latter crystallizes monoclinically with the following cell parameters: a = 10.258(1) Å, b = 17.589(3) Å, c = 19.723(2) Å, β = 92.95(1)°, space group P21/n, Z = 4. IrIII is in the centre of a slightly distorted pc2- ligand and coordinates pyridine and iodide in a trans-arrangement. The average Ir-Niso distance is 1.995(5) Å (Niso: isoindole N atom), the Ir-Npy and Ir-I distan­ces are 2.102(5) and 2.657(1)Å, respectively. By a similar oxidation of [{Rh(py)pc2- }2] only [Rh(py)(I)pc2- ]·py is obtained. Solid state spectral properties with diagnostic absorption bands at 1360. 1456, 5620 and 19800 cm-1 confirm the mixed-valent diphthalocyaninate(1.5-).
The Thermal Isomerization of a Tetrahydro-2,3-disilanaphthalene into a 1,2-Disilacyclobutane -The Conversion of a Formal Silene [2+4] Cyclodimer into the [2+2] Cycloadduct
Authors: Krempner Clemens , Kempe Rhett , Oehme Hartmut
Published: August 2018

1,2,3,8a-Tetrahydro-1 -mesityl-5,7,8a-trimethyl-2,2,3,3-tetrakis(trimethylsilyl)-2,3-disilanaphthalene (3), the formal [2+4] cyclodimer of the transient 2-mesityl-1,1-bis(trimethylsilyl)-silene (2), on thermal treatment gradually isomerizes to give a mixture of the [2+2] products (E)-and -predominantly -(Z)-3,4-dimesityl-1,1,2,2-tetrakis(trimethylsilyl)-1,2-disilacyclo-butane [(E/Z)-4], By prolonged heating or at higher temperatures both (E/Z)-3 and (Z)-4 are converted into (E)-4, the thermodynamically most stable head-to-head dimer of 2. Possible pathways of the isomerization processes are discussed.
Hydrogenation of Toluene over La0.8Sr0.2Fe1-xCoxO3-z Perovskite Catalysts
Authors: Schinzer Carsten , Saymeh Riyadh A , Asfour Hassan M
Published: August 2018

The hydrogenation of toluene over perovskites of composition La0.8Sr0.2Fe1-x CoxO3-z (x = 0.0, 0.2, 0.5, 0.8 and 1.0) is reported. The catalyst material has been prepared by the coprecipitation method using maleic acid as the complexing agent. The activity for the gas phase reaction of toluene and hydrogen at temperatures between 50 °C to 300 °C is reported for as-prepared and activated materials.

The conversion has been found to be nearly temperature-independent over the as-prepared-per­ ovskites with a maximum of 40% conversion found for a composition La0.8Sr0.2Fe0.5Co0.5O2.86. Activation by an oxygen treatment at 500 °C was successful to enhance the activity of the Co-rich perovskites. All of these catalysts show a complete conversion of toluene at 100 °C, but activity decreases by time due to a reduction of the catalyst material. Again, La0.8Sr0.2Fe0.5Co0.5O2.86 exhibits the slowest loss of activity. A model for its special properties is mainly attributed to the p-type conduction behaviour.

The conversion behaviour of the perovskite type catalysts investigated here is compared to the results obtained with noble-metal supported catalysts and it can be concluded, that the perovskites exhibit higher conversion rates, maximum temperatures and higher cracking onset temperatures than these.
Über die Bildung von N,N-Bistrifluormethylhydroxylammoniumsalzen (CF3)2N(X)OX+MF6- (X = H, D; M = As, Sb) / On the Formation of N,N-Bistrifluoromethylhydroxylammonium Salts (CF3)2N(X)OX+MF6- (X = H, D; M = As, Sb)
Authors: Minkwitz Rolf , Jakob Jens
Published: August 2018

Abstract The preparation of the N,N-Bistrifluoromethylhydroxylammonium hexafluorometallates (CF3)2N(X)OX+MF6- (X = H, D; M = As, Sb) is reported. The new compounds were characterized by IR, Raman, Mass, 1H , 19F and 13C NMR spectroscopy. In addition we present our approach to the preparation of H-subsituted N,N-Bistrifluoromethylhydroxylammonium hexafluorometallates (CF3)2N(Y)OH+MF6- (Y = CH3, Cl, F; M = As, Sb).
Polysulfonylamine, XC [1] Carbonsäure-Dimere, Wasser-Dimere und 18-Krone-6-Moleküle als Baugruppen eines supramolekularen Kettenpolymers: Darstellung und Struktur von (CH2CH2O)6 • 4H2O • 2HN(SO2C6H4-4-COOH)2 / Polysulfonylamines, XC [1] Carboxylic Acid Dimers, Water Dimers and 18-Crown-6 Molecules as Building Blocks in a Supramolecular Chain Polymer: Synthesis and Structure of (CH2CH2O)6 · 4H2O · 2HN(SO2C6H4-4-COOH)2
Authors: Wijaya Karna , Moers Oliver , Blaschette Armand , Jones Peter G
Published: August 2018

The ternary title complex (2) is readily obtained by co-crystallization of 18-crown-6 (18C6) and di(4-carboxybenzenesulfonyl)amine (1) from hot water and was characterized by low-temperature X-ray diffraction. The crystal structure (triclinic, space group P1̄) displays one-dimensional polymeric sequences [(H2O)2···18C6···(H2O)2···{HN(SO2C6H4-4-COOH)2}2] in which the molecules are associated through seven independent hydrogen bonds. The 18C6 ring lies on a crystallographic inversion centre and adopts the common pseudo-D3d conformation. On both sides, the ring is flanked by a strongly hydrogen-bonded water dimer H2O-H-OH. This species forms three weak O-H-O bonds to alternating ether oxygen atoms and accepts a strong N-H-O bond from the adjacent acid dimer (1)2. The water dimers thus act as ideal donor-acceptor balancing links between the hexafunctional polyether and the monofunctional NH groups of the (1)2 dimers. The (1)2 dimer itself is formed by two symmetry related cyclic O-H···O interactions (both H disordered) of the well-known carboxylic acid dimer type. To this effect, molecule 1 adopts a folded, pseudo-Cs symmetric conformation with stacked carboxyphenyl groups.
Synthese und Eigenschaften von trans-Bisnitro-phthalocyaninato(2-)iridat(III) und Pyridin-nitro-phthalocyaninato(2-)iridium(III); Kristallstruktur von linear- Bis(triphenylphosphin)iminium-trans-Bisnitro-phthalocyaninato(2-)iridat(III) / Synthesis and Properties of trans-Bisnitro-phthalocyaninato(2-)iridate(III) and Pyridine-nitro-phthalocyaninato(2-)iridium(III); Crystal Structure of linear- Bis(triphenylphosphine)iminium trans-Bisnitro-phthalocyaninato(2-)iridate(III)
Authors: Hückstädt Heiner , Homborg Heiner
Published: August 2018

Reaction of bis[phthalocyaninato(2-)iridium(II)] ([(Irpc2-)2]) with nitric oxide in pyridine yields nitrosyl-containing intermediates that are immediately oxidized by air yielding pyri-dine-nitro-phthalocyaninato(2-)iridium(III) ([Ir(py)(NO2)pc2-]). Linear-bis(triphenylphos-phine)iminium trans-bisnitro-phthalocyaninatoiridate(III) (1(PNP)trans[Ir(NO2)2pc2-]) is prepared by air-oxidation of [(Irpc2-)2] in dichloromethane in the presence of (PNP)NO2. It crystallizes in the triclinic space group P1̄ (no. 2) with the following cell parameters: a =10.649(1) Å, b = 12.357(1) Å, c = 12.841(1) Å, α = 75.47(1)°, β = 67.88(1)°, γ = 65.31(1)°, Z = 1. IrIII is in the centre of a slightly waving pc2- ligand coordinating two nitro ligands in an eclipsed fram-arrangement. The average Ir-Niso distance is 1.993(2) Å (Niso: isoindole N atom), the Ir-N distance is 2.189(3) Å (N: nitrite N atom), respectively. The structural data of the nitrite ion are: d(N-O) = 1.194(4) and 1.042(5) Å, ∠(O-N-O) = 131.7(4)°). Spectral properties with diagnostic IR absorption bands at 820, 1331 and 1398 cm-1 confirm the nitro coordination.
Preparation of Some New C19-Gibberellin Derivatives for Biochemical Studies
Authors: Ali Muhammad Shaiq , Hanson James R. , Ahmad Viqar Uddin
Published: August 2018

During the course of synthetic studies on gibberellins, three new derivatives (5, 6 , 10) of C19-gibberellin series have been prepared. These derivatives will be used as precursors for the biochemical preparations of plant growth regulating inhibitors.
Chemischer Transport intermetallischer Phasen IV: Das System Fe - Ge/Chemical Vapour Transport of Intermetallic Phases IV: The System Fe - Ge
Authors: Bosholm O. , Oppermann H. , Däbritz S.
Published: August 2018

Six phases exist in the binary system iron-germanium Fe3Ge, β, η, Fe6Ge5, FeGe and FeGe2. All phases could be prepared by chemical transport with iodine as transport agent in the temperature range between T1 (600 °C) and T2 (950 °C). Two phase diagrams have been known in the literature from specific experiments of chemical vapour transport. It is now possible to decide which phase diagram is the most valid description.
A Simple High-Yield Synthesis of Gallium(I) Tetrachlorogallate(III) and the Reaction of Digallium Tetrachloride Tetrahydrofuran Solvate with 1,2-Diols
Authors: Schmidt Eva S. , Schier Annette , Mitzel Norbert W. , Schmidbaur Hubert
Published: August 2018

Gallium(I) tetrachlorogallate(III) Ga[GaCU] was prepared in quantitative yield by thermal de­composition of dichlorogallane [HGaCl2]2, which is readily available from Et3SiH and [GaCl3]2. The reaction of catechol with solutions of this gallium(I) tetrachlorogallate(III) in tetrahydrofuran leads to the evolution of hydrogen gas and affords a dinuclear gallium(III) complex with penta-coordinate metal atoms chelated and bridged by mono-deprotonated catechol ligands. In the crystalline phase tetrahydrofuran molecules are hydrogen-bonded to the hydroxy groups: [Ga(1,2 -OC6H4OH)Cl2(C4H8O)]2. The reaction with pinacol also gives hydrogen and the analogous product [Ga(OCMe2CMe2OH)Cl2(C4H8O)]2. The structures of the two compounds have been determined by X-ray diffraction. A mechanism of the new reaction has been proposed which involves oxidative addition of the diol to the solvate (THF)Cl2Ga-GaCl2(THF) present in the tetrahydrofuran solution to give a gallium hydride intermediate.
Ethylboration of Stannyl-Substituted Sulfur Diimides
Authors: Herberhold Max , Gerstmann Silke , Wrackmeyer Bernd
Published: August 2018

Bis(sulfurdiimido)tin compounds of the type R2Sn[(NSN)tBu]2 [R = Me (2a), Et (2b)] re­ act with triethylborane Et3B by rearrangement and N-ethylation to give the novel aminoborane derivatives R2Sn[N(tBu)SN(Et)BEt2]2 (5a, b), in the same way as nBu3Sn(NSN)tBu (1) reacts with Et3B to give nBu3Sn[N(tBu)SN(Et)BEt2] (4). In contrast, 2c (R = tBu) and tris(sulfurdiimido)tin compounds RSn[(NSN)tBu]3 [R = Me (3a), nBu (3d)] react with Et3B mainly by Sn- and S-ethylation, accompanied by extensive decomposition. 1H, 11B , 13C, 15N and 119Sn NMR spectroscopy served for the structural assignment in solution.
Synthesis of Novel Tetracarboxylato Dirhenium(III) Compounds and Crystal Structure of [Re2(1-Adamantylcarboxylate)4Cl2] · 4 CHCl3
Authors: Shtemenko Alexander V. , Golichenko Alexander A. , Domasevitch Konstantin V.
Published: August 2018

The coordination compounds o f the general formula Re2 (L)4X2 (X = Cl, Br; L = 1 -adamantyl-carboxylate and 1 -adamantylacetate) have been prepared and characterized by means of UV-VIS spectroscopy (20000 cm-1 , δ → δ*). The crystal and molecular structure of Re2(AdCOO)4Cl2 · 4 CHCl3 solvate was determined by X-ray diffraction. The units Re2(AdCOO)4Cl2 adopt a centrosymmetric dinuclear array with each metal atom coordinated in a distorted octahedron comprising one rhenium and one chlorine atoms (Re-Cl 2.505(2) Å) and four carboxylate oxygen atoms in the equatorial plane. The rhenium-rhenium separation of 2.2300(5) Å corresponds to quadruple bond between the metal atoms. All R e-0 bonds have an almost uniform length (2.017(4) -2.032(4) Å) and do not differ essentially from the parameters reported for related compounds. The closest environment of the Re2(AdCOO)4Cl2 molecules in the crystal comprises weak Cl---HC hydrogen bonds with the chloroform molecules and significantly shortened van der Waals contacts Cl---Cl, 3.46 Å.
Synthesis of α-Tocopheryl Glycosides
Authors: Witkowski S. , Wałejko P.
Published: August 2018

An unusual course of d-α-tocopherol glucosylation by the Helferich method was observed. The product distribution very depended on acid catalyst and solvent used. The β-glucoside was accompanied by an unsaturated α-glucoside. Other unsaturated d-α-tocopheryl glucosides were obtained by reactions with acetylated glucal and 2-acetoxy glucal.
Synthesis of 3,4-Dihydro-2H-pyrans by Hetero-Diels-Alder Reactions of Functionalized α,β-Unsaturated Carbonyl Compounds with Styrenes
Authors: Bogdanowicz-Szwed Krystyna , Pałasz Aleksandra
Published: August 2018

Cycloadditions of 3-aryl-2-benzoyl-2-propenenitriles 1a,b to styrene (2a) and its methyl or methoxy-substituted derivatives 2b-d proceed regio- and diastereoselectively yielding cis and trans diastereoisomers of 2,4,6-triaryl-3,4-dihydro-2H-pyran-5-carbonitriles 3 and 4 in 59-72% yield. Cycloadducts cis-3 were the major products. Reaction of 5-(4-nitrobenzylidene)-1,3-dimethylbarbituric acid (5) with styrenes 2a-d afforded diastereoisomeric mixtures of 2H-pyrano[2,3-d]pyrimidine-2,4(3H)-diones cis-6 and trans-7 in 71 - 78% yield.
Notizen: Optical Outer-Sphere Charge Transfer and Photoreactivity of the Ion Pair Tetrabutylammonium Tetrabutylborate
Authors: Kunkely Horst , Vogler Arnd
Published: August 2018

The ion pair [N(n-butyl)4]+[B(n-butyl)4]- in CCl4 shows a BR4
- → NR4
+ outer-sphere charge transfer (OSCT) absorption at λ = 306 nm (sh, ε = 420 dm3 M-1 cm-1). OSCT excitation of the ion pair in CH2Cl2 (λirr > 275 nm) leads to a photo­ lysis with ∅ = 1.5 x 10-3 at λirr = 280 nm. Octane is formed as photoproduct.
Notizen: Cocrystallisation of Trimethylchlorostannane with a Distannoxane
Authors: Mitzel N orbert W. , Lustig Christian , Scharfe Sandra
Published: August 2018

Partial hydrolysis of a mixture of Me2SnCl2 and Me3SnCl affords an aggregate of the composition [Sn2Cl(O)(OSnMe3)(Me)4]2, which cocrystallises with two equivalents of Me3SnCl to form endless bands of {[Sn2Cl(O)(OSnMe3)(Me)4]2·2Me3SnCl}∞ linked through Sn ··· Cl intermolecular contacts.
Bleispezies PbX und PbX2 als Brückenliganden in übergangsmetallorganisch geschützten Koordinationsverbindungen/ Leadspecies PbX and PbX2 as Bridging Ligands in Organometallic Protected Coordination Compounds
Authors: Rutsch Peter , Huttner Gottfried
Published: August 2018

The disodium salt Na2[{(CO)5Cr}2Pb(NO3)2], Na2·1, which contains a lead center in a (4+2) coordination mode, reacts with tetraphenylphosphonium halides [Ph4P]X to give the tetrahedral compounds [Ph4P]2[{(CO)5Cr}2PbX2] (X = Cl: 2a; X = Br: 2b; X = I: 2c). Substitution of the nitrate groups of Na2·1 by alcoxides leads to binuclear compounds of the type [{(CO)5Crg2Pb(μ2-OR)2Pb{Cr(CO)5}2]2- (R = Et: 3a; R = n -Pr: 3b; R = i-Pr: 3c; R = Allyl: 3d). NMR experiments show that these dimeric compounds are in equilibrium with the monomeric species [{(CO)5Cr}2PbR]- .Trialkylphosphanes react with Na2·1 to give the neutral phosphane complexes [{(CO)5Cr}2Pb(PR3)2] (R=Me: 4a; R=Et: 4b; R = n-Bu: 4c), which show dynamic behaviour in solution. All of the novel compounds have been characterized by X-ray analysis, as well as by the usual analytic and spectroscopic techniques. 207Pb-NMR data of Cr(CO)5- bound lead species are reported for the first time.
Crystal Structure and Vibrational Behaviour of Aqua Di(saccharinato)di(nicotinamide)copper(II)
Authors: Parajón-Costaa Beatriz S. , Baran Enrique J. , Piro Oscar E. , Castellano Eduardo E
Published: August 2018

The crystal structure of [Cu(sac)2(nic)2(H2O)] (sac = saccharinate anion; nic = nicotinamide) has been determined by single-crystal X-ray diffraction. It crystallizes in the monoclinic space group C2/c with Z = 4 and the Cu(II) ion presents a CuN4O square pyramidal coordination. Some comparisons with related structures are made and the most important features of its IR spectrum were also discussed.
Neue bifunktionelle Silazane und ihr Kondensationsverhalten: 3-Methyl-2,2,4,4-tetrakis(methylamino)-1-phenyl-[1,3,2,4]diazadisiletidin, 1,3-Dichloro-2-phenyl-1,1,3,3-tetrakis(dimethylamino)disilazan, 3-Methyl-2,2,4,4-tetrakis(dimethylamino)-1-phenyl-[1,3,2,4]diazadisiletidin und 2,2,4,4-Tetrakis(dimethylamino)-1-phenyl-[1,3,2,4]diazadisiletidin/New Bifunctional Silazanes and their Condensation Reactions: 3-Methyl-2,2,4,4-tetrakis(methylamino)-1-phenyl-[1,3,2,4]diazadisiletidine, 1,3-Dichloro-2-phenyl-1,1,3,3-tetrakis(dimethylamino)disilazane, 3-Methyl-2,2,4,4-tetrakis(dimethylamino)-1-phenyl-[1,3,2,4]diazadisiletidine and 2,2,4,4-Tetrakis(dimethylamino)-1-phenyl-[1,3,2,4]diazadisiletidine
Authors: Bzik S. , Jansen M.
Published: August 2018

3-Methyl-2,2,4,4-tetrakis(methylamino)-1-phenyl-[1,3,2,4]diazadisiletidine (1), 1,3-Dichloro- 2-phenyl-1,1,3,3-tetrakis(dimethylamino)disilazane (2), 3-Methyl-2,2,4,4-tetrakis(dimethylamino)- 1-phenyl-[1,3,2,4]diazadisiletidine (3) and 2,2,4,4-Tetrakis(dimethylamino)-1-phenyl-[ 1,3,2,4]diazadisiletidine (4) have been synthesized as potential precursors for the preparation of porous oxygen-free solids. All compounds were characterized by crystal structure analysis. 1 crystallizes monoclinically, P21/c, a = 8.44(1), b = 19.56(1), c = 10.68(1) Å, β = 109.4(1)° and Z = 4 (R1 = 8.7%, wR2 = 20.7%, 1545 independent reflections). 2 crystallizes triclinically, P1̄, a = 8.011(2), b = 8.424(2), c = 16.082(2) Å, β = 91.08(1)°, β = 93.89(1)°, γ= 105.71(1)° and Z = 2 (R1 = 3.0%, wR2 = 7.9%, 3657 independent reflections). 3 crystallizes monoclinically, P21/c, a = 29.746(2), b = 21.590(2), c = 13.331(2) ) Å, β = 102.95(1)° and Z = 16 (R1 = 4.3%, wR2 = 9.3%, 6667 independent reflections). 4 crystallizes triclinically, P1̄, a = 10.450(1), b = 10.467(1), c = 17.948(1) ) Å, α = 97.43(1)°, β = 98.73(1)°, γ = 90.08(1)° and Z = 4 (R1 = 10.2%, wR2 = 25.8%, 3586 independent reflections). Polycondensation of 1 and ammonolysis and polycondensation of 2 yield amorphous solids with different porosities.
N,N′-Bis(silyl)ethylendiamine und 1,3-Diaza-2-silacyclopentane – Synthese, Reaktionen, Strukturen/ N,N′-Bis(silyl)ethylenediamines and 1.3-Diaza-2-silacyclopentanes – Synthesis, Reactions, Crystal Structures
Authors: Diedrich Friedhelm , Ebker Christina , Klingebiel Uwe , Reiche Clemens , Labahn Thomas , Magull Jörg , Noltemeyer Mathias
Published: August 2018

Ethylenediamine reacts with chlorosilanes to give N,N′-bis(silyl)ethylenediamines [(H2CNHSiRR′R″)2, 3: R, R′ = Me; R″ = CMe3; 4: R = H; R′, R″= CMe3; 5: R,R′ = CMe3, R″ = OH]. In the reaction of N,N,N′-tris(trimethylsilyl)ethylenediamine with SiF4 the difluoro-bis(1.1.4- tris(trimethylsilyl)ethylenediamino)silane (6) is obtained. The 1.3-diaza-2-silacyclopentanes R2Si[N(SiMe2R′)CH2]2, 7 - 10 (7: R = Cl, R′= Ph; 8: R = Cl, R′ = CMe3; 9: R = H, Cl, R′ = CMe3; 10: R = Br, R′ = CMe3) are isolated from the reactions of the corresponding bis(silyl)ethylenediamines and halosilanes in Et2O with NEt3 as HHal acceptor. Dilithium derivatives of N,N′-bis(silyl)ethylenediamines react with fluorosilanes with formation of the 1.3-diaza-2-silacyclopentanes, R2Si[N(SiMe2R′)CH2]2 (11 - 13) (11: R = F,R′ =Me; 12: R = F, R′ = CMe3; 13: R = CHMe2, R′ = Me). N-Fluoro-di(tert-butyl)silyl-N,N′-bis(trimethylsilyl)- ethylenediamine (14) is formed in the reaction of lithiated bis(trimethylsilyl)ethylenediamine with F2Si(CMe3)2. 8 reacts in amolar ratio 1:2 withNaNH2 or NaOMe with formation of 15 and 16, respectively · R2Si[N(SiMe2CMe3)CH2]2, 15: R = NH2; 16: R = OMe]. 1.3-Bis(tert-butyldimethylsilyl)- 2-tert-butyldimethylsiloxy-2-fluoro-1.3-diaza-2-silacyclopentane is the product of the reaction of 12 with LiOSiMe2CMe3. The crystal structures of 6 and 13 have been determined.
Synthesis and Separating Properties of Tris(Merrifield Peptide Resin)
Authors: Kim Dong Won , Kim Chang Suk , Lee Nam-Soo , Ryu Haiil , Kim Jong Seung
Published: August 2018

A triazacrown ion exchanger, 1,13,16-trioxa-4,7,10-triazacyclooctadecane (TOTA)-4,7,10- tris(Merrifield peptide resin) was synthesized. This resin has a capacity of 0.1 meq/g dry resin. The resin was used for the elution chromatographic separation of lithium isotopes. Upon column chromatography [0.2 cm I. D. x 35 cm height] using 3.0 M NH4Cl solution as an eluent, the single stage separation factor of 1.027 was obtained. The heavier isotope, 7Li+, was enriched in the resin phase, while the lighter isotope, 6Li+, was enriched in the solution phase.
Metallkomplexe mit biologisch wichtigen Liganden, CXLXXX [1]. Kationische Bis(α-Aminosäuremethylester)-N,O-Chelatkomplexe von Palladium(II) [Pd(NH2CHRCO2Me)2]2+(BF4–)2/ Metal Complexes of Biologically Important Ligands, CXLXXX [1]. Cationic Bis(α-Amino Acid Methylester)-N,O-Chelate Complexes of Palladium(II) [(Pd(NH2CHRCO2Me)2]2+(BF4–)2
Authors: Schapp Jan , Beck Wolfgang
Published: August 2018

Reactions of the palladium(II) complexes trans-Cl2Pd(L-NH2CHRCO2Me)2 with AgBF4 in dichloromethane give the cationic chelate complexes [Pd(L-NH2CHRCO2Me)2]2+(BF4-)2 (R =CHMe2, CMe3, CH2CHMe2, CH2Ph, CH2CO2Me) inwhich the α-amino acid methylesters function as bidendate ligands. The complexes 1 - 5 are highly sensitive towards water.
57Fe NMR Spectroscopy of Some Sila-[1]ferrocenophanes and a Phospha-[1]ferrocenophane
Authors: Wrackmeyer Bernd , Tok Oleg L. , Ayazi Anahid , Hertel Frank , Herberhold Max
Published: August 2018

57Fe NMR spectra (11.66 MHz) of the 1,1-diorganosila-[1]ferrocenophanes, [Fe(C5H4)2]- SiR1R2 (1) (R1 = R2 = Me) and (2) (R1 = Me, R2 = Ph), the 1-chloro-1-organosila-[1]ferrocenophanes [Fe(C5H4)2]Si(Cl)R1 3 (R1 =Me) and 4 (R1 = Ph), and of 1,1-dichlorosila-[1]ferrocenophane, [Fe(C5H4)2]SiCl2 5, were measured. All 57Fe resonance signals are shifted to lower frequencies with respect to ferrocene, the largest shift being observed for 5 (-147.7 ppm). The influence of chloro substituents at silicon in comparison to organo groups is much more pronounced in the ferrocenophanes than in non-cyclic 1-silyl- or 1,1-di(silyl)-ferrocene derivatives. In the case of -2,2,6,6-tetramethylpiperidin-1-yl-phospha-[1]ferrocenophane, [Fe(C5H4)2]P(tmp) 6, the 57Fe nucleus is deshielded (129.8 ppm) with respect to ferrocene, and the coupling constant 2J(57Fe,31P) = 3.4 Hz was measured for the first time.
Polymeric Double [Cu(NCS)] Chains in the Crystal Structure of [Cu2(Me2Ea)2(SCN)2]∞ (HMe2Ea = 2-Dimethylaminoethanol) (NewP olymorph) and the Dimeric Structure of its DMSO Adduct
Authors: Vinogradova Elena A. , Vassilyeva Olga Yu. , Kokozay Volodymyr N. , Skelton Brian W.
Published: August 2018

A new polymorph of the copper(II) thiocyanate complex with 2-dimethylaminoethanol, [Cu2(Me2Ea)2(NCS)2]∞ (HMe2Ea = 2-dimethylaminoethanol, HL) 1, was isolated in the attempted synthesis of a mixed-metal complex from zerovalent copper, cadmium oxide and ammonium thiocyanate in CH3CN solution of HL in air. [Cu2(Me2Ea)2(NCS)2(DMSO)2] 2 is a product of recrystallization of 1 from DMSO. X-ray analysis carried out on single crystals for both compounds revealed that 1 is a rare example of a 1D coordination polymer consisting of two chains in which the metallic centres are connected through single end-to-end NCS groups. The chains are inter-linked through alkoxo-bridges of L groups between the neighboring copper atoms. Complex 2 is a centrosymmetric dimer composed of two CuL(NCS)DMSO units linked by alkoxo-bridges of L groups.
Notizen: Synthesis and Characterization of Nadorite: PbSbO2Cl
Authors: Porter Yetta , Halasyamani P. Shiv
Published: August 2018

The first labortory synthesis and characterization of the mineral Nadorite, PbSbO2Cl, is reported. The material was synthesized by combining PbCl2, PbO and Sb2O3. Powder X-ray diffraction data on the polycrystalline product is consistent with the previously reported crystal structure on the mineral. Infrared and thermogravimetric data are also present.
Dicyanomethylene Compounds as Cyanation Reagents
Authors: Döpp Dietrich , Jüschke Sabine , Henkel Gerald
Published: August 2018

Ethenetetracarbonitrile (2, in benzene solution) and 1,3-dioxoindan-2-ylidene propanedinitrile (4, in ethanol or acetonitrile solution) act on N-aryl-2,3-dihydro-1H-benz[d,e]isoquinolines 6a-d and N-aryl-6,7-dihydro-5H-dibenz[c,e]azepines 11a-d via hydride abstraction followed by addition of cyanide to the iminium carbon atom forming the corresponding 1- and 5-carbonitriles 9a-d and 13a-d, respectively, in moderate to medium yields.Additionally , the known 1,3-dihydroxy-2H-inden-2-ylidenepropanedinitrile 15 and a novel dispirocyclopropane (17) are formed from 4 in the reaction with 6 in acetonitrile and ethanol, respectively. The structures of 17 and 6-(4-methylphenyl)-6,7-dihydro-5H-dibenz[c,e]azepine-5-carbonitrile have been unambiguously confirmed by single-crystal X-ray crystallography.
Synthesis and Reactivity of Diborane(4)yl Complexes
Authors: Braunschweig Holger , Koster Margot
Published: August 2018

Reaction of various 1,2-dihalodiboranes(4) with Na[(η5-C5H4R)M(CO)3] yielded the diborane(4)yl complexes [X(Me2N)B-B(NMe2){ η5-(C5H4R)M(CO)3}] (5, X = Cl, R = H, M = Mo; 6, X = Br, R = Me, M = Mo; 7, X = Br, R = H, M = W ;8, X = Br, R = Me, M = W )and [Cl(C4H8N)B-B(NC4H8){ η5-(C5H5)W(CO)3}] (9). The reactivity of diborane(4)yl complexes of the type [X(Me2N)B-B(NMe2){η5-(C5H5)M(CO)n}] (X = Cl, Br; M(CO)n = Fe(CO)2, Mo(CO)3) with respect to substitution of X and CO, respectively, was investigated. The novel derivatives [MeO(Me2N)B-B(NMe2){η5-(C5H5)Mo(CO)3}] (10), [MeO(Me2N)B-B(NMe2){η5-(C5H5)Fe(CO)2}] (11), and [Br(Me2N)B-B(NMe2){η5-(C5H5)- Mo(CO)2(PMe3)}] (12) were obtained. All compounds were fully characterised in solution by NMR spectroscopy and by elemental analysis.
Crystal Structures of Piperazinium Tetrabromocadmate(II)-Monohydrate [C4H12N2]CdBr4 · H2O, PiperaziniumTetraiodocadmate(II) [C4H12N2]CdI4, and Bis(trimethylsulphonium) Tetrabromocadmate(II) [(CH3)3S]2CdBr4
Authors: Ishihara Hideta , Horiuchi Keizo , Gesing Thorsten M. , Dou Shi-qi , Buhl J.-Christian , Erk Peter
Published: August 2018

Piperazinium tetrabromocadmate(II)-monohydrate, [C4H12N2]CdBr4 · H2O (1) crystallizes with isolated [CdBr4]2- anions, piperazinium cations, and water molecules (monoclinic, P21/c, Z = 4, a = 698.7(1), b = 1348.6(3), and c = 1432.4(3) pm, β = 92.97(3)˚ at 293 K). The crystal structure of 1 is almost the same as that reported in Inorg. Chim. Acta 187, 141 (1991). The crystal of piperazinium tetraiodocadmate(II), [C4H14N2]CdI4 (2) consists of isolated [CdI4]2- anions and piperazinium cations (orthorhombic,P212121, Z=4, a = 903.2(5), b = 1226.3(6), and c = 1307.9(7) pm at 293 K). The room temperature phase of bis(trimethylsulphonium) tetrabromocadmate( II), [(CH3)3S]2CdBr4 (3) has isolated [CdBr4]2- anions and trimethylsulphonium cations (orthorhombic, P212121, Z = 4, a = 911.3(1), b = 1329.2(2), and c = 1454.7(2) pm at 293 K).
Crystal Structures and Magnetic Properties of (2,2'-Dipyridyl)-(3-methoxysalicylaldiminato)copper(II) Perchlorate and (2,2'-Dipyridyl)-(4-methoxysalicylaldiminato)copper(II) Perchlorate
Authors: Elerman Y. , Elmali A. , Svoboda I.
Published: August 2018

The mixed-ligand dinuclear complexes (2,2'-dipyridyl)-(3-methoxysalicylaldiminato)copper( II) perchlorate (1) and (2,2'-dipyridyl)-(4-methoxysalicylaldiminato)copper(II) perchlorate (2)were synthesized and their crystal structures determined. Both structures consist of a dimeric unit involving a planar Cu2O2 group. In both structures, the coordination sphere of the Cu atoms can be described as an elongated octahedron where the basal plane is formed by the twoN atoms of the 2,2'-dipyridyl molecule and the two O atoms of the salicylaldehyde anion. The phenoxo O atom is the negative ligand of the monomeric unit. Two apical Cu-O contacts complete the 4+2 coordination of the Cu atoms. They correspond to one of the O atoms of the perchlorate anion and to the O atom of the nearest salicylaldehyde molecule. Variable-temperature magnetic susceptibility data obey the Curie-Weiss law with Θ = -10.3(2) K for 1 and -10.1(2) K for 2. The decrease of the effective magnetic moment from 1.89(7) μB at 300 K to 1.77(7) μB at 70 K for 1 and from 1.88(8) μB at 300 K to 1.76(8) μB at 70 K for 2 and the negative Weiss constants indicate weak antiferromagnetic interactions between the two copper atoms in the dimeric units.
Studies in the Acid Catalysed Glycosylation of α-Tocopherol
Authors: Witkowski S. , Wałejko P.
Published: August 2018

Condensation of α-tocopherol and 2,2,5,7,8-pentamethyl-6-hydroxychroman (the model compound) with peracetylated glucose, mannose and galactose was carried out. The influence of various acidic catalysts on the chemical yield and the stereochemical outcome of the glycosylation was investigated.
Two Hydroxo Bridged Dinuclear Lanthanide Phen Complexes: [Ln2(phen)4(H2O)4(OH)2](phen)2(NO3)4 with Ln = Tm, Yb
Authors: Wei Dan-Yi , Zheng Yue-Qing , Lin Jian-Li
Published: August 2018

Two isostructural hydroxo bridged dinuclear lanthanide phen complexes of general composition [Ln2(phen)4(H2O)4(OH)2](phen)2(NO3)4 with Ln = Tm (1), Yb (2) were prepared by reactions of the corresponding lanthanide nitrate and phenanthroline monohydrate in CH3OH/H2O at pH = 5.5. They crystallize in the triclinic space group P1̄ (no. 2) with the cell dimensions: a = 11.233(1), b = 11.456(1), c = 14.011(2) Å , α = 93.91(1)°, β = 98.20(1)°, γ = 108.21(1)°, V = 1683.0(3)Å3, Z = 1 for 1 and a = 11.236(1), b = 11.480(2), c = 13.986(2)Å , α = 93.91(1)°, β = 98.17(1)°, γ = 108.33(1)°, V = 1682.9(3) Å3, Z = 1 for 2. The crystal structures are composed of the hydroxo bridged dinuclear [Ln2(phen)4(H2O)4(OH)4]4+ complex cations, hydrogen bonded NO3
- anions and π-π stacking (phen)2 dimers. The lanthanide atoms are each surrounded by two phen ligands, two H2O molecules and two μ-OH groups to complete a tetragonal antiprismatic LnN4O4 coordination. Via two common μ-OH groups, two neighboring tetragonal antiprisms are condensed to form a centrosymmetric dinuclear [Ln2(phen)4(H2O)4(OH)4]4+ complex cation. The complex cations and (phen)2 dimers are assembled via π-π stacking interactions and hydrogen bondings into 2D layers parallel to (101̄), between which the hydrogen bonded NO3
- anions are sandwiched. The Tm compound shows paramagnetic behavior with an experimental magnetic moment of 7.51 μB at room temperature. No magnetic ordering is evident down to 5 K. Over the temperature range 70 - 300 K, the Yb compound obeys the Curie-Weiss law with an experimental magnetic moment of 4.32 μB at room temperature and shows weak ferrimagnetic behavior at low temperature.
Synthesis and Electronic Spectra of (N-1-Naphthyl-ethylenediamine)- dichloroplatinum(II). Fluorescence of the Appended Naphthyl Substituent
Authors: Kunkely Horst , Vogler Arnd
Published: August 2018

Pt(naph-en)Cl2 with naph-en =N-(1-naphthyl)- ethylenediamine was synthesized and spectroscopically characterized. The complex shows a fluorescence at λmax = 405 nm, which originates from the appended naphthyl substituent present as an electronically isolated chromophore.
Synthesis and Structure of Bis-Urea Phenazines
Authors: Fricke Tom , Dickmans Anton , Jana Umasish , Zabel Manfred , Jones Peter G. , Dix Ina , König Burkhard , Herges Rainer
Published: August 2018

Substituted phenazines 7 and 15 with two urea units have been prepared and characterized. X-ray structure analyses are reported for intermediates 5, 9, 11b and 12. According to theoretical calculations the geometry of the two urea moieties in phenazines 7 and 15 should be well suited for the binding of trigonal planar anions, such as nitrate. NMR titration revealed that compound 15 indeed shows a weak interaction with nitrate ions in DMSO.
Synthesis and Structural Characterization of [Cu(NH2CH2C6H4N=CHC5H5N)Cl2]
Authors: Datta Amitabha , Karan Nirmal Kumar , Mitra Samiran , Rosair Georgina
Published: August 2018

The compound [Cu(NH2CH2C6H4N=CHC5H5N)Cl2] (1) containing the tridentate Schiff base ligand, which is the 1:1 condensation product of pyridine- 2-carboxaldehyde and 2-amino benzyl amine, was synthesised and its crystal structure has been determined. It is monomeric, space group P1, a = 7.704(1), b = 9.308(2), c = 11.228(2) A˚ , α= 68.97(2), β= 82.23(1), γ= 67.70(1)° and Z = 2. The crystal structure of 1 is based on a five coordinate copper centre with trigonal bipyramidal geometry. The six membered chelate ring possesses a half-chair conformation with C7 most out of the plane made by Cu1, N2, N3, C8 and C9. There is a hydrogen bond between Cl2 and an amine hydrogen H2A of a neighbouring molecule related by a centre of inversion
A Simple Conversion of 2'-Benzyloxyflavanone to Pterocarpan
Authors: Kiss Loránd , Szilágyi László , Antus Sándor
Published: August 2018

A new synthesis of cis-6aH,11aH-pterocarpan (1a) was achieved via its trans-isomer 1b starting from the readily available 2'-benzyloxyflavanone (2b).
Manganese(II), Iron(II), Cobalt(II) and Nickel(II) Complexes of Methanesulfonic Acid Hydrazide. Crystal Structure of trans-Dichlorotetrakis(methanesulfonic Acid Hydrazide-N2)cobalt(II) and trans-Dichlorotetrakis(methanesulfonic Acid Hydrazide-N2)nickel(II)
Authors: Dodoff Nicolay I. , Kubiak Maria , Kuduk-Jaworska Janina
Published: August 2018

The complexes [M(MSH)4Cl2] (MSH = CH3SO2NHNH2; M = Mn (1), Fe (2), Co (3) and Ni (4)) were synthesized and characterized by elemental analysis, molar electric conductivity, IR and d-d electronic spectra. The X-ray single crystal analysis revealed for 3 (triclinic, P1̄ , a = 8.077(2), b = 8.622(2), c = 8.742(2) A° , α = 71.98(3), β = 75.30(3), γ = 64.11(3)°, V = 515.8(2)A° 3, Z = 1) and 4 (triclinic, P1̄ , a = 8.050(2), b = 8.588(2), c = 8.686(2) Å , α = 73.35(3), β = 75.76(3), γ = 63.94(3)°, V = 511.8(2) Å3, Z = 1) that MSH is coordinated via the amino N atom, the donor atoms and the metal are coplanar, and the Cl ligands are in trans-configuration. On the basis of IR data a similar structure is suggested for 1 and 2. The electronic spectra of 3 and 4 are interpreted by the Angular Overlap Model and bonding parameters are derived: eσ(N) = 3384(15), eσ(Cl) = 2788(25), eπ(Cl) = 150(21) cm-1 for 3, and eσ(N) = 3668(21), eσ(Cl) = 2602(150), eπ(Cl) = -21(128) cm-1 for 4.
Crystal Structure of trans- [ReCl2(dppp)2]Cl · ½H2O (dppp = 1,3-bis(diphenylphosphino)propane)
Authors: Piro Oscar E. , Gambino Dinorah , Benítez Julio , Kremer Eduardo , Baran Enrique J.
Published: August 2018

The crystal structure of trans-[ReCl2(dppp)2]- Cl · ½H2O (dppp = 1,3-bis(diphenylphosphino)- propane), a potentially useful radiopharmaceutical agent, was determined by single crystal X-ray diffractometry. It belongs to the tetragonal space group P4̄ with Z = 2. The Re(III) ion is in a quasioctahedral environment coordinated to a pair of symmetry related dppp molecules, acting as bidentate ligands, and two axial chloride ions.
Synthesis and Structure of 1,3-Diisopropyl-4,5-dimethylimidazolium N,N'-Diphenylureate
Authors: Kuhn Norbert , Al-Sheikh Ahmed , Steimann Manfred
Published: August 2018

1,3-Diisopropyl-4,5-dimethylimidazolium diphenylureate (4) has been obtained from 2,3- dihydro-1,3-diisopropyl-3,4-dimethylimidazol-2-ylidene (3) and N,N'-diphenylurea in good yield. The crystal structure of 4 contains dimeric ureate anions linked by unsymmetrical NHN hydrogen bonds while only weak interactions are detected between the imidazolium cations and the anions.
Novel and Facile Synthesis of Pyrazolo[3,4-d]pyrimidines
Authors: Abu Elmaati Tarek M.
Published: August 2018

The reaction of 6-hydrazinopyrimidine-2,4-dione derivative 1 with alkyl or aryl isocyanates 2a-d resulted in a novel and facile synthesis of pyrazolo[3,4-d]pyrimidine derivative 5a-d in good yield.
NdClSeO3 and ErClSeO3: First Chloride-Selenites of the Rare Earth Elements
Authors: Wickleder Mathias S.
Published: August 2018

Violet single crystals of NdClSeO3 (Pnma, Z = 8, a = 1115.3(2), b = 535.19(6), c = 1356.8(1) pm, Rall = 0.0281) were obtained from the reaction of Nd2O3, NdCl3, and SeO2 in evacuated silica ampoules. The analogous procedure using Er2O3 and ErCl3 led to pink single crystals of ErClSeO3 (Pnma, Z = 4, a = 721.8(1), b = 692.2(1), c = 874.3(2) pm, Rall = 0.0305). The crystal structure of NdClSeO3 contains two crystallographically different neodymium ions. Nd(2)3+ is coordinated by four oxygen atoms and four chloride ions while eight oxygen atoms and one Cl− ion are connected to Nd(1)3+. The linkage of the polyhedra leads to a three-dimensional structure. In the structure of ErClSeO3 the Er3+ ion is coordinated by two Cl− ions, three O-monodentate SeO3
2− and one O,O-chelating SeO3
2− groups. The [ErO5Cl2] polyhedra can be seen as pentagonal bipyramids, which are connected in the [010] direction via opposite edges of oxygen atoms to infinite chains. These are further linked via chloride ions to give a three-dimensional network. In both crystal structures a prominent stereochemical activity of the lone electron pairs of the selenite ions can be observed.
Quadratate Und Hydrogenquadratate Cyclischer Stickstoffbasen Mit Schicht-, Ketten- und Leiterstrukturen / Squarates and Hydrogensquarates of Cyclic Nitrogen Bases with Layer-, Chainand Ladder-Structures
Authors: Mattes Rainer , Ebbing Jörg , Grüss Annette , Köppe Jens , Majcher Krystyna
Published: August 2018

The synthesis and single crystal X-ray structures of four adducts of squaric acid with cyclic nitrogen bases are reported. Extensive hydrogen bonding, ionic interactions and (in one case) π-π-interactions lead to layered, and to two- and three-dimensional assemblies. [Pyrimidinium][ hydrogenquadratate] (1) has a layer structure, consisting of head-to-tail infinite chains of pyrimidinium and [HC4O4]− ions, which are cross-linked by short N-H···O and C-H···O hydrogen bonds. [C9H11N2][HC4O4] ・0.5H2C4O4 (2), the adduct of a benzodiazepin and squaric acid, has a ladder-structure. Chains of [HC4O4]− ions and H2C4O4 molecules in alternating order form the ladder-beam. Layers of cations and anions in the ratio 2:1 build the crosspieces at an angle of 49° to the beam. The layers contain dimers of [HC4O4]− ions. [H2L2][HC4O4]2 (3) with L2 = 5,6,7,8,9,14,15,16,17,18-decahydrodibenzo[e,l]-1,4,8,11-tetraaza-cyclotetradecine shows zigzag chains made of [HC4O4]− ions. Between the [H2L2]2+ and the [HC4O4]− ions π-π interactions exist besides up to four N-H···O hydrogen bonds. The [H2L2]2+ ions possess two different conformations. [H2cyclam][C2O4] ·4H2O (4) contains strongly undulated layers of the composition [C4O4 ·4H2O]2−. The cations, which show two intramolecular N-H···N hydrogen bonds with N···N distances of 2.870 (3) Å , are interlinked at an angle of 41.5°.
The Reduction of Pyridine to 1,4-Dihydropyridine by Lithiumtetrahydroborate in the Presence of Water
Authors: Nöth Heinrich , Warchhold Marcus
Published: August 2018

In the presence of water lithium tetrahydroborate is capable of reducing pyridine to 1,4- dihydropyridine. The product, lithiumtetrakis(pyridine) tetrakis(1,4-hydropyridyl)borate, was isolated and characterized by NMR and IR spectroscopy and single crystal X-ray diffraction. [Li(py)4][B(pyH)4].2(1,4-dioxane) crystallized in space group P42/n, Z = 2. Similarly, NaBH4 can also reduce pyridine in the presence of water and equivalent amounts of LiCl or ZnCl2.
Conductivity, Electrodeposition and Magnetic Property of Cobalt(II) and Dysprosium Chloride in Zinc Chloride-1-Ethyl-3-Methylimidazolium Chloride Room Temperature Molten Salt
Authors: Hsu Hsin-Yi , Yang Chao-Chen
Published: August 2018

Electric conductivity of the molten zinc chloride-1-ethyl-3-methylimidazolium chloride phases has been measured by a computerized system using the d.c. four-probes method. The sequence of the conductivities for the different component melts is ZnCl2-EMIC > ZnCl2-EMIC-CoCl2 > ZnCl2- EMIC-DyCl3 > ZnCl2-EMIC-CoCl2-DyCl3. The results may be explained in terms of the viscosity increase due to the complex formation.

The electrochemistry and the nucleation mechanism of cobalt(II) or/and dysprosium chloride in acidic ZnCl2-EMIC melts have been investigated by cyclic voltammetry and chronoamperometry at different temperatures, respectively. The results of the SEM and VSM analyses reveal that reduction of Dy3+ to Dy2+ may have occurred, while reduction of Dy3+ to Dy(0) is conjectured to play no role. Moreover, the results of chronoamperometry experiments show that nucleation in the alloy electrodeposition is instantaneous, and that, as the applied deposition potential becomes more negative, the nucleation density increases, which rapidly shortens the time required for the diffusion zones to overlap.

Electrodeposition of a Dy-Co-Zn alloy on a Ni or Cu sheet from the 50-50 mol% ZnCl2-EMIC melt containing 1.687 mol% CoCl2 and 1.114 mol% DyCl3 has been accomplished, and the morphology and the composition have been analyzed by SEM and EDS, respectively. The magnetism of the deposited layer is discussed based on the results of the VSM analysis.
Rietveld Refinement of the Crystal Structure of α-Be3N2 and the Experimental Determination of Optical Band Gaps for Mg3N2, Ca3N2 and CaMg2N2
Authors: Reckeweg Olaf , Lind Cora , Simon Arndt , DiSalvo Francis J.
Published: August 2018

α-Be3N2 powder was obtained by reacting Be metal with dry, flowing N2 at 1600 K. The product contained 5.9(7) wt.% of BeO. The anti-bixbyite structure suggested earlier was verified through Rietveld refinement on the basis of X-ray powder data (Ia3 (#206); a = 814.518(6) pm). The optical band gaps of α-Be3N2, Mg3N2 and Ca3N2 are compared with newly measured values for Mg3N2, Ca3N2 and CaMg2N2.