bluuebunny/crossref_metadata_2025 huggingface dataset:
Secondary Interactions in Gold(I) Complexes with Thione Ligands. 1. Three Ionic Chlorides
Authors: Friedrichsa Steffi , Jones Peter G.
Published: August 2018

Secondary interactions in the structures of [(etu)2Au]+Cl−.H2O (1), [(etu)2Au]+Cl− (2) and [(Me-etu)2Au]+Cl− (3) (etu = imidazolidine-2-thione) have been analysed. Within the cations, the torsion angle C-S...S-C is effectively the sole degree of freedom, and varies from almost eclipsed for 1 (−20°) via −79° for 2 to exactly 180° in 3. Both 1 and 2 form ten-membered rings in which the water molecule or the chloride ion respectively act as hydrogen bond acceptor to two NH donors of the cation. Further classical hydrogen bonds lead to the formation of double layer structures. Compound 3, in which the gold atom lies on an inversion centre and the chloride on a twofold axis, utilises its one N-H...Cl contact to form chains of hairpin bends, with Au...Cl contacts in the chain direction. Weak hydrogen bonds C-H...Cl and C-H...Au play at best a minor role in 1, but are more pronounced in 2 and 3.
Chemical Composition and Antitumor Activities from Givotia madagascariensis
Authors: Krebsa Hans C. , Duddeck Helmut , Malik Shahid , Beil Winfried , Rasoanaivo Philippe , Andrianarijaona Mamy
Published: August 2018

Two new erythroxylane diterpenes, named givotin A (1) and givotin B (2) were isolated from the bark of Givotia madagascariensis. Their structures have been established as 3α,12α-dihydroxy- 4(19),15-erythroxyladiene (1) and 3α-hydroxy-4(19),15-erythroxyladiene (2), respectively, on the basis of one and two-dimensional NMR spectroscopic studies (1H, 13C, COSY, HMQC, HMBC, NOESY, NOE difference spectra) as well as on mass spectral analysis. In addition six known compounds (3 - 8) have been isolated and identified. Cleistanthol (3), spruceanol (4) and 1,2- dihydroheudelotinol (5) demonstrated significant antitumor activities against three tumor cell lines (HM02, Hep G2, MCF7).
An Elegant Synthetic Route to 3-Cyano-5,6-dihydro-2-ethoxy-4-phenyl-pyrido[2,3-a]carbazoles
Authors: Danish Isravel A. , Prasad Karnam J. R.
Published: August 2018

2-Benzylidene-1-oxo-1,2,3,4-tetrahydrocarbazoles (1a - e) obtained from the corresponding 1- oxo-1,2,3,4-tetrahydrocarbazoles on reaction with malononitrile in dry benzene with sodium hydride afforded 3-cyano-5,6-dihydro-2-ethoxy-4-phenyl-pyrido[2,3-a]carbazoles (2a - e) in good yields. A plausible mechanism for the formation of the title compound has been proposed and all the compounds were characterised by IR, NMR, mass spectral methods and elemental analysis.
DFT and G2MP2 Calculations of the N-N Bond Dissociation Enthalpies and Enthalpies of Formation of Hydrazine, Monomethylhydrazine and Symmetrical and Unsymmetrical Dimethylhydrazine
Authors: Bohn Manfred A , Klapötke Thomas M
Published: August 2018

In a combined DFT (B3LYP) and G2MP2 theoretical study the following enthalpies of formation (ΔH°f) and bond dissociation enthalpies (BDE) for hydrazine, methylhydrazine (MMH), 1,1- dimethylhydrazine (UDMH) and 1,2-dimethylhydrazine (SDMH) were determined: BDE/kJ mol−1: N2H4, 278±4; MMH, 272±4; UDMH, 259±12; SDMH, 272±12. ΔH°f/kJ mol−1: N2H4, 95±6; MMH, 94±4; UDMH, 80±4; SDMH, 91±4. The bond enthalpy for the N-N bond in hydrazine amounts to BE (N-N, H2N−NH2) = 159±4 kJ mol−1.
The Crystal Structures of [N,N’-Bis(3-methoxysalicylidene)-1,3- diaminopropane]nickel(II) and -copper(II)
Authors: Elmali Ayhan , Zeyrek Celal T , Elerman Yalcin
Published: August 2018

[N,N′’-Bis(3-methoxysalicylidene)-1,3-diaminopropane]nickel(II) dihydrate [Ni(C19H20N2O4)· 2(H2O)] 1 and [N,N′-bis(3-methoxysalicylidene)-1,4-diaminobutane]copper(II) [Cu(C20H22N2O4)] 2 have been synthesized and their crystal structures determined. Crystals of compound 1 are orthorhombic, space group Pnma, a = 7.509(3), b = 22.070(7), c = 11.532(4) Å, V = 1611.1(12) Å3, Z = 4 and Dc = 1.498 g·cm−3. The molecule 1 has mirror symmetry, but the ligand is not planar. The two parts of the Schiff base moieties are folded so as to form an angle of 21.6(1)°. The Ni atom is in a distorted octahedral geometry and coordinated by the donor atoms of the ligand in the horizontal plane and of two water molecules. Crystals of compound 2 are monoclinic, space group P21/c, a = 9.488(1), b = 21.918(3), c = 8.413(1) Å, β = 91.45(1)°, V = 1749.0(4) Å3, Z = 4 and Dc = 1.587 g·cm−3. The Cu atom is coordinated by an N2O2 donor set from the imine-phenol ligand in a distorted planar geometry, with the two phenolate O atoms deprotonated. The Cu-O bond lengths are 1.854(3) and 1.868(3)Å . The Cu-N bond lengths are 1.931(3) and 1.950(3) Å, the dihedral angle between the two 3-methoxysalicylidene groups is 43.4(1)°.
Dialkoxy-Substituted, C1-Symmetric Metallocenes: Synthesis and Catalytic Behavior in the Propylene Polymerization Reaction
Authors: Schlögl Martin , Rieger Bernhard
Published: August 2018

The synthesis of a series of C1-symmetric metallocene complexes rac-[1-(5,6-dialkoxy-2-methyl- 1-η5-indenyl)-2-(9-η5-fluorenyl)ethane]zirconium dichlorides (alkyl: n-butyl, n-hexyl, n-octyl, n-decyl) is described. These complexes are versatile catalysts in the polymerization of propylene after in situ activation with triisobutylaluminum (TIBA) and Ph3C[B(C6F5)4] in toluene and heptane solution. All catalysts show higher solubility and improved polymerization properties in industrially used hydrocarbon solvents (e.g. heptane). However, the molecular weights and isotacticity values of the resulting polypropylene materials are decreased compared to the ethoxy-bridged analogue rac- [1-(5,6-ethylenedioxy-2-methyl-η5-indenyl)-2-(9-η5-fluorenyl)ethane]zirconium dichloride. A possible explanation is based on enhanced interaction of the active catalyst centers with Al(III) scavenger molecules even at low Al : Zr ratios, leading to reversible chain transfer.
Preparation, Crystal Structure and Spectroscopic Characterization of [Ga(OH)(SO4)(terpy)(H2O)] · H2O (terpy=2,2’:6’,2-Terpyridine): The First Characterized Gallium(III) Sulfato Complex
Authors: Sofetis Andreas , Papaefstathiou Giannis S. , Terzis Aris , Raptopoulou Catherine P. , Zafiropoulos Theodoros F.
Published: August 2018

The reaction of Ga2(SO4)3·18H2O and excess 2,2′:6′,2″-terpyridine (terpy) in MeOH / H2O leads to [Ga(OH)(SO4)(terpy)(H2O)]·H2O (1·H2O] in good yield. The structure of the complex has been determined by single-crystal X-ray crystallography. The GaIII atom in 1·H2O is 6-coordinate and ligation is provided by one terdentate terpy molecule, one monodentate sulfate, one terminal hydroxide and one terminal H2O molecule; the coodination polyhedron about the metal is described as a distorted octahedron. There is an extensive hydrogen-bonding network in the crystal structure which generates corrugated layers parallel to bc. The new complex was characterized by IR and 1H NMR spectroscopy. The spectroscopic data are discussed in terms of the nature of bonding
DNA-Binding Properties of Iron(II) Mixed-Ligand Complexes Containing 1,10-Phenanthroline and Dipyrido[3,2-a:2’,3’-c]phenazine
Authors: Mudasir  , Wijaya Karna , Tjahjono Daryono H. , Yoshioka Naoki , Inoue Hidenari
Published: August 2018

An iron(II) mixed-ligand complex with 1,10-phenanthroline (phen) and dipyrido[3,2-a:2’,3’- c]phenazine (dppz), [Fe(phen)2(dppz)]2+, has been synthesized. The DNA-binding properties of the mixed-ligand complex have been studied in terms of equilibrium binding constant, thermodynamic parameter, thermal denaturation as well as Pfeiffer effect upon binding to DNA. The spectrophotometric titration of [Fe(phen)2(dppz)]2+ with calf thymus DNA (ct-DNA) has shown that the iron(II) mixed-ligand complex binds effectively to ct-DNA in an intercalation mode as indicated by remarkable hypochromicity (ca. 36%) and moderate bathochromic shift (8 nm) of the absorption spectra. This intercalative mode is supported by a significant increase (Δ Tm = 21 °C) in the melting temperature (Tm) of ct-DNA at R([complex]/[ct-DNA]) = 1.5. The binding of [Fe(phen)2(dppz)]2+ to ct-DNA is entropically driven as characterized by a positive enthalpy change and a large negative TΔ S term. An intense CD signal in the UV and visible region develops upon addition of ct-DNA to the racemate solution of [Fe(phen)2(dppz)]2+. This has revealed that a shift in diastereomeric inversion equilibrium takes place in the solution to yield an excess of one enantiomer of the DNA-iron(II) complex (Pfeiffer effect). The striking resemblance of the CD spectral profiles to those of the corresponding Δ -enantiomer indicates that Δ -[Fe(phen)2(dppz)]2+ is preferentially bound to ct-DNA
Regioselective Conversion of Anhydro Sugars into Halohydrins and X-Ray Study
Authors: Shah Syed Tasadaque A. , Abdel-Jalil Raid J. , Khan Khalid M. , Heinrich Angelica M. , Richter Markus , Voeltera Wolfgang
Published: August 2018

A rapid, easy, regio- and stereoselective synthesis of 3-halo-3-deoxy sugars using titanium tetrahalides is described. To fully confirm the stereochemistry of the synthetic products, the X-ray structure of benzyl 3-chloro-3-deoxy-β -L-xylopyranoside was determined
C-Branched Glycals as Monosaccharidic Push-Pull Butadienes
Authors: Rudloff Ivo , Bari Ahmed , Feist Holger , Michalik Manfred , Reinke Helmut , Peseke Klaus
Published: August 2018

Treatment of 2(3)-formyl-glycals 1, 3, 5 with alkyl cyanoacetates afforded 2(3)-[(E)-2-cyano-2- alkoxycarbonyl-vinyl]-2(3)-deoxy-1,5(2, 6)-anhydro-hex-1(2)-enitols 2, 4, 6 which were reacted with aniline to yield nicotinonitrile acyclo-C-nucleosides 7, 9. Nicotinic acid ester acylo-C-nucleosides 11 were obtained by the reaction of 2,6-anhydro-1,4,5-tri-O-benzyl-3-[(E)-2-cyano-2-alkoxycarbonylvinyl]- 3-deoxy-D-erythro-hex-2-enitols 6 with ammonia.
Preparation and Characterisation of N,N-Disubstituted 2-Amino-5H-selenophenes
Authors: Zug Ines , Hartmann Horst
Published: August 2018

The reaction of N,N’-persubstituted selenoacrylamides with alkyl bromoacetates gives rise to the formation of alkyl derivatives of N,N-disubstituted 2-aminoselenophene-5-carboxylates which can be transformed by saponification into corresponding 5-carboxylic acids. These compounds decompose by heating under formation of hitherto unknown N,N-disubstituted 2-amino-5H-selenophenes their spectral and chemical properties were outlined.
Isoxazolinium Salts in Asymmetric Synthesis. 1. Stereoselective Reduction Induced by a 3’-Alkoxy Stereocentre. A New Approach to Polyfunctionalized β-Amino Acids* [1, 2]
Authors: Henneböhle Marco , Le Roy Pierre-Yves , Hein Matthias , Ehrler Rudolf , Jäger Volker
Published: August 2018

A new approach to optically active N-methylamino acids is presented, relying on stereoselective reduction of N-methylisoxazolinium salts with a dioxyethyl side-chain. The diastereoselectivity of the reduction step is studied systematically, in comparison with that of respective isoxazolines. A two-step transformation of isoxazolinium salts - with NaBH3(OAc) and subsequent catalytic hydrogenation as well as a one-pot reduction by catalytic hydrogenation led to high (95:5 and 87:13) diastereomeric ratios of protected erythro-N-methylaminopentanetriols. The hydroxyethyl side-chain is elaborated by oxidation to afford the β -N-methylamino acid 37, exemplifying the potential of this strategy.
Facile Synthesis of Novel N-Aryl-4,5,6,7-tetrahydro-benzosultams by Oxyfunctionalisation of Bicyclic Isothiazolium Salts*
Authors: Siegemund Anja , Hartung Christine , Eilfeld Alexander , Sieler Joachim , Schulze Bärbel
Published: August 2018

3-Hydroxy- (17a - j) and 3-alkoxy-4,5,6,7-tetrahydro-benzosultams 18a-m were prepared in good yields by oxidation of the bicyclic isothiazolium salts 10 with magnesium monoperoxyphthalate (MMPP·6H2O) in acetonitrile or corresponding alcohol. A HPLC-API-MS(MS) method was used to monitor the oxidation process of 10 with MMPP. 3-Oxo-4,5,6,7-tetrahydro-benzosultams 19a - c, h, j were also obtained.
Neue Barium-Oxoantimonate(III): Darstellung und Kristallstruktur von Ba3[SbO3]2 und Ba2[Sb2O5]/New Barium Oxoantimonates(III): Synthesis and Crystal Structures of Ba3[SbO3]2 and Ba2[Sb2O5]
Authors: Emmerling Franziska , Zimper Sabine , Röhr Caroline
Published: August 2018

The barium oxoantimonates(III) Ba3[SbO3]2 (triclinic, P1̄, a = 615.2(8), b = 981.4(3), c = 1215.4(5) pm, α =74.683(9), β =89.710(6), γ =71.464(7)°, Z =2, R1=0.0802) and Ba2[Sb2O5] (orthorhombic, Cmcm, a = 401.0(3), b = 1450.6(7), c = 636.6(6) pm, Z = 4, R1 = 0.0589) have been synthesized from melts of elemental barium and antimony oxide Sb2O3 at a temperature of 800 °C. Their oxoantimonate building units are strongly influenced by the stereochemically active lone pair electrons of the pentele element: In the Ba rich compound Ba3[SbO3]2, isolated ψ tetrahedra [SbO3]3− are present, in Ba2[Sb2O5], which crystallizes with the Sr2Bi2O5 structure type, two of these ψ tetrahedra are condensed to form nucelar units [Sb2O5]4−. The two compounds are compared in terms of structure and bonding with the alkali antimonates on one hand and with the alkaline earth bismutates on the other.
Magnetic Films of Cobalt/Aluminum Electrodeposited from the Room Temperature Molten Salts AlCl3-BPC-CoCl2
Authors: Yang Chao-Chen , Wu Te-Ho , Shu Min-Fong
Published: August 2018

The electric conductivities of molten mixtures of aluminum chloride-butylpyridinium chloridecobalt chloride (AlCl3-BPC-CoCl2) were measured using a computerized direct-current method. The conductivities of all the melts increased with increasing temperature. The electrodeposition of Co/Al films from the AlCl3-BPC melt containing a small amount of CoCl2 has been studied by cyclic voltammetry. Compact and smooth Co/Al thin films could be obtained at a deposition potential of −0.4 V. The surface morphology and the composition of the electrodeposited thin films were studied using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The magnetic properties of the deposited thin films have been investigated via magnetic force microscopy (MFM) and vibrating sample magnetometry (VSM). Higher magnetization and smooth domains of Co/Al layers could be obtained at the deposition potentials of −0.1 V and −0.4 V, respectively.
Divalent Europium in 1
∞[Eu(Pz)2(Pz-H)2]: The First Unsubstituted Pyrazolate and Cp Analogous Pyrazole Complex of a Rare Earth Element in One
Authors: Quitmann Catharina C. , Müller-Buschbaum Klaus
Published: August 2018

Bright yellow crystals of 1
∞[Eu(Pz)2(Pz-H)2] were obtained by the reaction of europium metal with a melt of pyrazole. According to single crystal X-ray analysis the compound exhibits a onedimensional chain structure including both unsubstituted pyrazolate anions as well as unsubstituted neutral pyrazole molecules as ligands. The latter are isoelectronic with the cyclopentadienyl anion and link two adjacent Europium(II) centers in an η1-σ -bridging as well as Cp analogous η5-π-binding mode, whilst the pyrazolate anions are N-η1-coordinating terminal ligands. In addition to the crystal structure, MIR, FarIR, Raman and UV/vis spectroscopic data are presented.
Convenient Route to Efavirenz Analogues as Potential non-Nucleoside HIV-1 Reverse Transcriptase Inhibitors
Authors: Hamed Atef A.
Published: August 2018

Treating 2-chloro-4-(4-chlorophenyl)-6-methylbenzo[d]-3,1-oxazinium hexachloroantimonate (1) with one equivalent of alcohol or mercaptane led, after hydrolysis with aq. NaOH, to the formation of 4,4-disubstituted-1,4-dihydro-2H-6-methyl-3,1-benzoxazin-2-ones (3). Large excess addition of alcohol afforded either 4’-chloro-2-isocyanato-5-methylbenzophenone disubstitutedketal (4) or N-{2- [(4-chlorophenyl)dialkoxymethyl]-4-methylphenyl} alkylcarbamate (5). Reaction of 4 with primary amines furnished 1-{2-[(4-chlorophenyl)dialkoxymethyl]-4-methylphenyl}-3-substituted urea (6).
Square Planar Complexes of Cu(II) with an N2O Donor Set of a New Schiff Base Ligand: Synthesis and Structural Aspects
Authors: Talukder Pritha , Datta Amitabha , Mitra Samiran , Rosair Georgina
Published: August 2018

The title compounds, [Cu(C16H23N2O)SCN] (1) and [Cu(C16H23N2O)N3] (2), containing a tridentate Schiff base ligand, which is the 1:1 condensation product of benzoylacetone and 2- diethylaminoethylamine, have been synthesised and their crystal structures determined. The structure of 1 is based on a four coordinate copper centre with square-planar geometry formed by the N2O donor set of the Schiff base and an N atom of the thiocyanate anion. A similar arrangement occurs in 2 with the N2O donor set of the Schiff base and an N atom of the azide anion. The Cu-N and Cu-O distances are 1.924(8), 2.073(8), 1.927(9) and 1.910(6)Å , for 1 and 1.960(4), 2.050(4), 1.935(4) and 1.907(3) for 2, respectively.
Polysulfonylamine, CLXIX. Intermolekulare Wechselwirkungen in kristallinen Di(organosulfonyl)aminen. Teil 1. Di(4-brombenzolsulfonyl)amin: Zwei Konformationspolymorphe und Strukturverwandtschaft eines Polymorphs mit dem entsprechenden 2,4-Dimethylpyridinium-Salz / Polysulfonylamines, CLXIX. Intermolecular Interactions in Crystalline Di(organosulfonyl)- amines. Part 1. Di(4-bromobenzenesulfonyl)amine: Two Conformational Polymorphs and the Structural Relationship of one Polymorph to the Corresponding 2,4-Dimethylpyridinium Salt
Authors: Lozano Virginia , Moers Oliver , Jones Peter G. , Blaschette Armand
Published: August 2018

Two crystal structures (polymorphs) of di(4-bromobenzenesulfonyl)amine (1), as determined by low-temperature single-crystal X-ray diffraction, are reported: Form A, monoclinic, P21/c, Z' = 1; form B: monoclinic, P21/c, Z' = 2. In A, the molecule adopts an extended conformation approximating to C2 symmetry, whereas the two independent molecules of form B display a folded hair-pin conformation with pseudo-mirror symmetry [torsion τ (C-S···S’-C’) and intercentroid distance dIC of the aromatic rings in A: 173.2° and 750.8 pm, in B: −5.4/−8.90° and 364.1/366.5 pm]. The packings of both polymorphs consist of layers, in which the molecules are connected by N-H···O hydrogen bonds in one and by Br···O interactions in the other dimension. The 1:1 onium salt (2; monoclinic, P21/n, Z' = 1) produced on N-deprotonation of 1 with 2,4-dimethylpyridine is structurally related to B. Its packing involves strands of formula units, whereby the anions retain the folded conformation (τ = 5.8°, dIC = 372.5 pm) and perfectly mimic the catemeric Br···O pattern of B, while the cations are isotactically connected to the anion backbone via an N-H(···O)2 three-centre bond. In all structures, a three-dimensional network of weak hydrogen bonds C-H···A (A = O, in 2 also N−) and C-H···Br contacts supports the controlling N-H···O and Br···O interactions; moreover, an intermolecular (π···π) stacking dimer of the type phenyl/phenyl and a (π···π) stacking trimer of the type phenyl/pyridinium/phenyl have been identified in A and 2, respectively. None of the structures exhibits very short bromine-bromine contacts suggestive of specific attractive forces.
The Structure of the Ligand Tri(1-cyclohepta-2,4,6-trienyl)phosphane, P(C7H7)3, in the Hexafluoroacetylacetonato Copper(I) Complexes, (hfac)Cu[P(C7H7)3]n (n = 1, 2)
Authors: Herberhold Max , Milius Wolfgang , Akkus Nilgün
Published: August 2018

The reaction of CuCl[P(C7H7)3] (1a) with sodium hexafluoroacetylacetonate, Na(hfac), leads to (hfac)Cu[P(C7H7)3] (2a), which in the presence of excess P(C7H7)3 (a) gives (hfac)Cu[P(C7H7)3]2 (3a). Whereas the 1:2 compound 3a is a pseudo-tetrahedral copper(I) complex with relatively long Cu-P (224.85(10) and 223.75(10) pm) and Cu-O (212.7(3) and 212.0(3) pm) distances, the 1:1 complex 2a may be described as having a distorted pseudo-trigonal coordination sphere (Cu-P 214.32(11) pm, Cu-O 196.6(3) and 208.1(3) pm), although one of the cyclohepta-2,4,6-trienyl substituents develops a weak additional interaction with the metal through its central C=C double bond (Cu-C 275.1 and 272.9 pm). The molecular geometries of the tri(1-cyclohepta-2,4,6-trienyl) complexes 2a and 3a are compared with those of the known tri(cyclohexyl)phosphane complexes, (hfac)Cu[P(C6H11)3]n (n = 1 (2b) and 2 (3b)), and related compounds.
Optically Active Transition Metal Compounds, 136 [1]. An Octahedral Molybdenum Complex (P-P’)Mo(CO)4 with a Chiral Secondary Phosphorus Atom
Authors: Brunner Henri , Grau Ilias , Zabel Manfred
Published: August 2018

Reaction of (η6-C6H5CH3)Mo(CO)3 with the easily accessible chiral chelate ligand P,P,Pʹ-tris- [(+)-9-phenyldeltacyclan-8-yl]-1,2-bis(phosphanyl)benzene P-P’ afforded the octahedral molybdenum carbonyl derivate (P-P’)Mo(CO)4 1 as a diastereomer mixture 1a (74%) and 1b (26%). Crystallization gave single crystals of (SP)-(P-P’)Mo(CO)4 1a. The X-ray structure analysis of compound 1a revealed the formation of an unusual triple-decker π-stack in the solid state.
Synthesis and Biological Evaluation of a “Natural” Insect Repellent
Authors: Csuk René , Niesen Anja
Published: August 2018

(11Z)-11,19-Icosadienyl acetate (1) has been shown to be an efficient repellent against the ant Myrmica rubra whereas its corresponding (11E) stereoisomer 2 does not exhibit any repellent activity at all. Several synthetic strategies for these two compounds have been evaluated.
Homoleptic Nickel(0) Phenyl Isocyanide Complexes
Authors: Hahn F. Ekkehardt , Münder Marco , Fröhlich Roland
Published: August 2018

The tetrakis(phenyl isocyanide)nickel(0) complexes [Ni(CNR)4](R = C6H5, 1; R= C6H3-2,6-Me2, 2; R = C6H4-2-NO2, 3) have been synthesized from [Ni(COD)2] and the corresponding phenyl isocyanides in toluene. Complexes 1 - 3 were characterized by X-ray diffraction. All three complexes contain a nickel atom which is coordinated in a slightly distorted tetrahedral fashion.
Antiferromagnetic Ordering in GdRhIn5
Authors: Łątkaa Kazimierz , Kmieć Roman , Rams Michał , Pacyna Andrzej W. , Zaremba Vasyl’ I. , Pöttgend Rainer
Published: August 2018

A polycrystalline sample of tetragonal GdRhIn5 (HoCoGa5 type, space group P4/mmm) was obtained by induction melting of the elements in a glassy carbon crucible in a water-cooled sample chamber and subsequent annealing at 670 K. X-ray powder data yielded the cell parameters a = 460.65(7), c = 743.52(12) pm. The magnetic and electronic properties of GdRhIn5 have been studied by magnetic susceptibility, electrical resistivity, and 155Gd Mössbauer spectroscopic measurements. Antiferromagnetic ordering is detected at 41.0(2) K. The results are discussed using a simple molecular field approximation.
Synthesis and Crystal Structure of a New Oxysulfide Gd6+xTi4 –xS10 – yO6+y (where x ~ 0.04 and y ~ 0.27)
Authors: Meignen Vincent , Meerschaut Alain , Cario Laurent , Lafond Alain
Published: August 2018

A new phase in the quaternary system Gd/Ti/S/O was obtained from a mixture of Gd2O3, Gd2S3, TiO2, TiS2 and Ti by a solid state reaction at 1323 K in a sealed fused-silica tube. The structure of Gd6+xTi4−xS10−yO6+y (where x ~ 0.04, and y ~ 0.27), was solved by single-crystal X-ray diffraction, with R(obs) = 2.69% for 2391 reflections (I > 3σ (I)) and 155 variables. This compound crystallizes with four formula units in the orthorhombic space group Pnma, and the lattice constants (Å ): a = 13.991(1), b = 3.7124(2), c = 34.029(3) Å. The structure is built up from the stacking of ribbons of five Gd-polyhedra alternating with ribbons of five Ti- and Gd/Ti-polyhedra along the a-axis. This is the first example of a rare earth (RE) and titanium oxysulfide compound that shows mixed RE/Ti sites together with pure RE- and Ti-sites. Gd6+xTi4−xS10−yO6+y is a mixed-valent titanium oxysulfide in which half of the Ti cations are Ti3+ and half are Ti4+.
On the Silicides EuIr2Si2 and Lu5Si3
Authors: Rodewald Ute Ch. , Heying Birgit , Johrendt Dirk , Pöttgen Rainer
Published: August 2018

EuIr2Si2 was synthesized from the elements in a sealed tantalum tube in a water-cooled sample chamber of an induction furnace. Lu5Si3 was obtained by arc-melting of the elements. Both silicides were investigated by X-ray powder and single crystal diffraction: BaAl4 type, I4/mmm, a = 407.4(1), c = 1010.8(7) pm, wR2 = 0.0492, 134 F2 values, 9 variables for EuIr2Si2 and Mn5Si3 type, P63/mcm, a = 820.0(1), c = 614.2(1) pm, wR2 = 0.0511, 311 F2 values and 12 variables for Lu5Si3. The iridium and silicon atoms in EuIr2Si2 build up a three-dimensional [Ir2Si2] network with Ir-Si and Si-Si interactions. The europium atoms fill cages within the network. The metal-rich silicide Lu5Si3 contains columns of face-sharing, empty Lu6 octahedra and isolated silicon atoms in a distorted tri-capped trigonal prismatic coordination. Chemical bonding in these silicides is briefly discussed.
From Yellow to Black: New Semiconducting Ba Chalcogeno-Germanates
Authors: Assoud Abdeljalil , Soheilnia Navid , Kleinke Holger
Published: August 2018

The new germanates Ba2GeSe4−δ Teδ (δ < 2.5) were prepared by reacting the elements under exclusion of air at 800°C, followed by slow cooling to room temperature. These germanates form the Sr2GeS4 type, monoclinic space group P21/m, with lattice dimensions of a = 699.58(4), b = 709.38(4), c = 917.38(6) pm, β = 109.135(1)◦, V = 430.11(4) ・ 106 pm3 (Z = 2) for Ba2GeSe4. The structure contains isolated GeSe4 tetrahedra. The oxidation states are assigned to be BaII, GeIV, and Se−II. The yellow color of this ortho-seleno-germanate is indicative of semiconducting behavior with an activation energy of 2.6 - 3.0 eV, and the black appearance of the seleno-telluro-germanates points towards gaps < 1.7 eV. Electronic structure calculations based on the LMTO approximation resulted in smaller gaps of 1.7 - 0.8 eV, a tendency that is typical for this calculation method.
Synthesis and Crystal Structure of the Tetra-nickel Substituted [Ni4(H2O)2(AsW9O34)2]10- Polyoxoanion
Authors: Drewes Daniel , Limanski Eva Melanie , Krebs Bernt
Published: August 2018

The new polyoxotungstate (NH4)6Na4[Ni4(H2O)2(AsW9O34)2] · 20 H2O (1) was synthesized in aqueous solution and characterized by IR and UV/Vis spectroscopy, energy dispersive X-ray fluorescence and single-crystal X-ray analysis. It contains the tetra-nickel substituted [Ni4(H2O)2(AsW9O34)2]10− polyoxoanion, in which the four Ni atoms are in a common plane and form a regular rhombus. 1 crystallizes in the monoclinic crystal system, space group P21/n with a = 11.849(2), b = 16.718(3), c = 21.243(4) Å , β = 100.48(3)◦, and Z = 2. The anions are linked via hydrogen bonds and sodium cations.
Chirale Erkennung bei Tris(diimin)-Metallkomplexen, 10. Vergleich der intermolekularen Wechselwirkungs- und Packungsmuster in der Reihe [Cr(bpy)3]n+(PF6)n (n = 0 – 3) / Chiral Recognition among Tris(diimine)-metal Complexes, 10. Comparison of Intermolecular Interactions and Packing Patterns in the Series [Cr(bpy)3]n+(PF6)n (n = 0–3)
Authors: Breu Josef , Zwicknagel Andrea
Published: August 2018

Due to their conformational rigidity, the corrugated, chiral molecular structure, and the variability in the central metal and its oxidation state, [M(bpy)3]n+ complexes are particularly well suited to study chiral recognition and to identify intermolecular interaction patterns in the crystalline state. For [Cr(bpy)3]n+(PF6)n (n=0 - 3) four oxidation states are readily accessible which allows to investigate the influence of the cation/anion ratio on the observed packing patterns.

The crystal structures of all four oxidation states are governed by so-called ‘π-π-interactions’. Apparently, in molecular salts the Madelung energy is less important as compared to classical inorganic salts.

Interestingly, [Cr(bpy)3](PF6) and [Cr(bpy)3](PF6)2 comprise the same homochiral layers. However, while the former crystallises as true racemate, the latter spontaneously resolves into a conglomerate. This two-dimensional building block of homochiral layers is the most popular structural motif in this class of compounds which has been observed in a great variety of racemic and homochiral stackings.
Crystal Engineering of a New Layered Polyiodide Using 1,9-Diammoniononane as a Flexible Template Cation
Authors: Reiß Guido J. , Engel Judith S.
Published: August 2018

The reaction of 1,9-diaminononane with hydroiodic acid in the presence of iodine gave a compound best described as 1,9-diammoniononane bis-triiodide iodine, (H3N-(CH2)9-NH3)[I3]2 · I2. The structure is built from two crystallographically independent I3
− anions, which are connected via secondary I···I interactions to the iodine molecules, and the 1,9-diammonioalkane cations are connected via weak hydrogen bonds to neighbouring iodine atoms. By a cooperative phenomenon, the shape and the functionality of the cation lead to a solid state structure that includes a polyiodide substructure with the formula 2
∞[I8]2− or 2
∞[I3 · I2 · I3]2−, is best described as a brick-shaped layered array. Its rectangular pores fit excellently with the hydrogen bonding functionality as well as with the conformational needs of the 1,9-diammoniononane template. The Raman spectrum shows typical bands of coordinated triiodide anions and iodine molecules. The thermal analysis (DSC/TG) of the title compound indicates decomposition at temperatures above 210°C.
Synthesis and Solid-State Structures of Alkyl-Substituted 3-Cyano-2-pyridones
Authors: Fischer Christian B. , Polborn Kurt , Steininger Harald , Zipse Hendrik
Published: August 2018

A series of 3-cyano-pyridones carrying a variety of alkyl substituents at C-5 and C-6 has been synthesized and their solid-state structures have been studied. Hydrogen bonding interactions between individual pyridone molecules lead either to the formation of symmetric dimers of the R2
2 (8) type or to helical chains of the C(4) type. Based on known and calculated structures for the 2-pyridone parent system, the solid-state structures can be divided in two groups representing cases with little external influence on the hydrogen bonding array (group A) and those with a larger external influence (group B).
Synthesis, Spectroscopic Studies and Crystal Structure of 5,5’-Dimethoxy- 3,3’-methanediyl-bis-indole as the Inhibitor of Cell Proliferation of Human Tumors
Authors: Maciejewska Dorota , Niemyjska Maria , Wolska Irena , Włostowski Marek , Rasztawicka Magdalena
Published: August 2018

5,5’-Dimethoxy-3,3’-methanediyl-bis-indole (3) was synthesized in a reductive cyclisation process from (E)-5-methoxy-2-nitro-β -morpholinestyrene. The solid state structure was probed by single crystal X-ray diffraction and 13C CP/MAS NMR methods. The results of the X-ray analysis indicate insignificantly different structure of both methoxyindole fragments of the molecule, and this is the main reason for the appearance of the double resonances in the solid state NMR spectrum. Interesting N-H· · ·π interactions were observed which may have a functional role in biological features of 3. 5,5’- Dimethoxy-3,3’-methanediyl-bis-indole at conc. 1 · 10−4 M reduces the growth of MCF7 (breast), NCI-H460 (lung), and SF-268 (NCS) cells to 21, 0, and 48%, respectively.
Luminescent Gold(I)-Thallium(I) Arrays through N-Bidentate Building Blocks
Authors: Fernández Eduardo J. , Jones Peter G. , Laguna Antonio , López-de-Luzuriaga José M. , Monge Miguel , Montiel Manuel , Olmos M. Elena , Pérez Javier
Published: August 2018

Heteropolynuclear gold(I)-thallium(I) complexes of the type [TlLn][Au(C6F5)2] (L = py (2), 2,2’- bipy (3), 1,10-phen (4) or 4,4’-bipy and THF (5); n = 1, 2) have been obtained from reactions of the corresponding N-donor ligands with the precursor {Tl[Au(C6F5)2]}n (1). The crystal structures of complexes 3 - 5 have been determined by X-ray diffraction showing one- (3, 4) or three-dimensional (5) arrays. All complexes are photoluminescent in the solid state at RT and at 77 K. The strong visible emissions of complexes 2 - 5 are displayed over a wide range of wavelengths (460 - 620 nm) depending on the environment of the thallium(I) centres and on the nature of the N-donor ligand.
Crystal and Molecular Structure of P(C6H5)5 · 0.5 THF
Authors: Müller Gerhard , Bildmann Ulrich Jürgen
Published: August 2018

Pentaphenylphosphorus crystallizes from tetrahydrofuran (THF) as P(C6H5)5・0.5 THF (triclinic space group: P1̅, a = 10.095(4), b = 10.252(3), c = 12.725(3) A° , α = 71.21(1), β = 76.98(3), γ = 87.12(1)°, Z = 2). Its molecular structure is an almost perfect trigonal bipyramid with significantly longer axial than equatorial P-CPh bonds (P-Cax 1.982(2)/1.979(2), P-Ceq 1.853(2)/1.845(2)/1.847(2) Å). It differs from the well established structure of solvent-free P(C6H5)5 (P. J. Wheatley, J. Chem. Soc. 2206 (1964)) in the relative orientation of the phenyl rings with respect to each other (axial rings) and with respect to the equatorial PC3 plane (equatorial rings) but not in the trigonal-bipyramidal (tbp) geometry at phosphorus. Differences in the geometry around the central atom had been found previously for Sb(C6H5)5 (square pyramid) and Sb(C6H5)5 · 0.5C6H12 (tbp) but not in As(C6H5)5 and As(C6H5)5 · 0.5 C6H12 (both tbp).
Intramolecular Carbene and Carbenoid Reactions of α-(Vinyloxy)silyl-α-diazoacetates
Authors: Daucher Birgit , Gettwert Volker , Striegler Ruth , Maas Gerhard
Published: August 2018

Thermolysis of α-[diisopropyl-1-(methylvinyl)oxysilyl]-α-diazoacetate 5a at 160 °C yields mainly 2,5-dihydro-1,2-oxasilole-3-carboxylate 6a and 3-[diisopropyl(methoxy)silyl]-2(5H)-furan- 2-one 7. From the thermolysis reaction of α-[diisopropyl-1-(phenylvinyl)oxysilyl]-α-diazoacetate 5b, only 1-oxa-2-sila-3-cylopentene-3-carboxylate 6b could be isolated in low yield. UV-irradiation of 5a,b generates 6a,b as the main products. The Rh2(C3F7COO)4-catalyzed decomposition of 5a provides primarily the ketene 2-[diisopropyl(methoxy)silyl]-pent-1-ene-1,4-dione (9) in high yield. After work-up, 3-[diisopropyl(methoxy)silyl]-2(3H)-furan-2-one 10a and 2(5H)-furanone 7 are obtained in relative amounts that depend on work-up conditions. Mechanistic pathways leading to the various products are proposed.
Base Catalyzed Synthesis of Novel Fused-Imidazoles from N-Vinyl-1H-imidazole
Authors: Aly Ashraf A.
Published: August 2018

Syntheses of various classes of fused-imidazoles are reported. The key to their successful synthesis depends on the reaction of N-vinyl-1H-imidazole with the π-deficient compounds under basic conditions. Reaction of the target imidazole with 1,1,2,2-tetracyanoethylene and dimethyl acetylenedicarboxylate afforded pyrrolo[1,2-a]imidazoles. On the other site, reaction of the target imidazole with 2-dicyanomethyleneindane-1,3-dione, 2,3-dicyano-1,4-naphthoquinone gave indanylimidazolo- [1,2-a]azepine and imidazolo[2,1-a]phenanthridine derivatives, respectively. Under basic reaction condition, various classes of imidazolo[2,1-a]isoquinolines were obtained by the reaction of N-vinyl- 1H-imidazole with 2,3,5,6-tetrachloro-1,4-benzoquinone, 2,3-dichloro-1,4-naphthoquinone, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone and 3,4,5,6-tetrachloro-1,2-benzoquinone.
Structure Refinement of BaIrIn2
Authors: Riecken Jan F. , Pöttgen Rainer
Published: August 2018

BaIrIn2 was synthesized from the elements in a sealed tantalum tube in an induction furnace. The indide was investigated by powder and single crystal X-ray data: Cmcm, a = 443.3(1), b = 1151.3(2), c = 806.0(1) pm, wR2 = 0.0471, 352 F2 values, and 16 variable parameters. The iridium and indium atoms build up two-dimensional [IrIn2]2− polyanions (279 - 281 pm Ir-In and 310-314 pm In-In) which are separated and charge-balanced by the barium atoms. The two-dimensional character of the polyanion is responsible for the strong moisture sensitivity of BaIrIn2. The coordination numbers for barium, iridium, and indium are 15, 9, and 12, respectively.
Synthesis and Structures of Some Aluminum Pseudohalides
Authors: Knabel Klaus , Nöth Heinrich
Published: August 2018

The reactions of bis(2,2,6,6-tetramethylpiperidino)aluminum bromide (tmp2AlBr) with Me3SiN3 or Me3SiCN lead to trimeric tmp2AlN3 and tmp2AlCN, respectively, while the reaction with Me3SiOCN produces the bicyclic compound [tmpCON(SiMe3)2]2′ , 3. Similarly, di(tertbutyl) aluminum bromide reacts with Me3SiCN to give tetrameric (Me3C)2AlCN, 4. The compounds (Me3C)2AlN3 and (Me3C)2AlOCN, obtained as oily products, have tetracoordinated Al atoms as shown by NMR spectroscopy, but the degree of oligomerization has not been determined.
Juglorescein, Juglocombins and Juglochromans: Structure of Juglomycin Dimers from Streptomycetes
Authors: Lessmann H. , Maskey R. P. , Fotso S. , Lackner H. , Laatsch H.
Published: August 2018

Novel juglomycin derivatives with a C28 skeleton were isolated from the Streptomyces strains 815 and GW4184. Juglorescein (1a) and juglocombin A (2a) and B (3a) are C,C dimers of juglomycin C (10) with a five membered ring between the two monomeric moieties. In the juglochromans A-D (4a, 5a, 6a, 6c), two juglomycin C (10) units are connected by C,C and C,O bonds forming a central isochroman or a chroman system. The structures of the new natural products were elucidated by detailed spectra analyses, by comparison of the NMR data with those of related compounds and by biosynthetic considerations. The new natural products were antimicrobially inactive.
Sesquiterpene Lactones from Elephantopus scaber
Authors: Than Ni Ni , Fotso Serge , Sevvana Madhumati , Sheldrick George M. , Fiebig Heinz H. , Kelter Gerhard , Laatsch Hartmut
Published: August 2018

The ethanolic and acetone extracts of the whole plant of Elephantopus scaber were found to contain ethyl hexadecanoate, ethyl-9,12-octadecadienoate, ethyl-(Z)-9-octadecenoate, ethyl octadecanoate, lupeol, stigmasterol, stigmasterol glucoside, deoxyelephantopin (1) and two new germacranolide sesquiterpene lactones named 17,19-dihydrodeoxyelephantopin (2) and iso-17,19- dihydrodeoxyelephantopin (3) whose stereostructures were determined by spectroscopic methods, comparison with reported data and single-crystal X-ray analysis.
Synthesis of Dimethylphosphinoyl Substituted α-Aminoarylmethanephosphonates
Authors: Cholakova Tsvetanka , Zagraniarsky Yulian , Hägele Gerhard , Tosheva Tania , Ivanova Bojidarka , Scopelliti Rosario , Varbanov Sabi
Published: August 2018

New dimethylphosphinoyl-substituted α-aminoarylmethanephosphonates 1a - f have been synthesized via addition of dimethyl or diethyl phosphites to Schiff bases and via Kabachnik-Fields reaction. The structure of the compounds was confirmed by elemental analysis, IR, 1H and 31P{1H} NMR spectroscopy, mass spectrometry and in two cases by X-ray diffraction.
The Crystal Structures Of Dimeric Di(tert-butyl)Aluminium And -Gallium Iodides
Authors: Tian Xin , Fröhlich Roland , Mitzel Norbert W.
Published: August 2018

The syntheses of ditbutylaluminium and -gallium iodide via metathesis reactions of the respective chlorides with lithium iodide are reported. The compounds were identified by elemental analyses, multinuclear NMR spectroscopy (1H, 13C, 27Al) and mass spectra (EI). The structures obtained by single crystal X-ray diffraction reveal that the new compound tBu2AlI crystallizes in the monoclinic crystal system, space group P21/n, as a dimer with a planar Al2I2 four-membered ring. The crystal structure of the monoclinic structure of tBu2GaI was redetermined. Its mass spectra reveal the existence of trimers and dimers in addition to the predominant monomeric species in gas phase
Ternary Thallides REMgTl (Re = Y, La – Nd, Sm, Gd – Tm, Lu)
Authors: Kraft Rainer , Pöttgen Rainer
Published: August 2018

The rare earth metal (RE)-magnesium-thallides REMgTl (RE = Y, La-Nd, Sm, Gd-Tm, Lu) were prepared from the elements in sealed tantalum tubes in a water-cooled sample chamber of a high-frequency furnace. The thallides were characterized through their X-ray powder patterns. They crystallize with the hexagonal ZrNiAl type structure, space group P62m, with three formula units per cell. Four structures were refined from X-ray single crystal diffractometer data: α = 750.5(1), c = 459.85(8) pm, wR2 = 0.0491, 364 F2 values, 14 variables for YMgTl; α = 781.3(1), c = 477.84(8) pm, wR2 = 0.0640, BASF = 0.09(2), 425 F2 values, 15 variables for LaMgTl; α = 774.1(1), c = 473.75(7) pm, wR2 = 0.0405, 295 F2 values, 14 variables for CeMgTl; a = 760.3(1), c = 465.93(8) pm, wR2 = 0.0262, 287 F2 values, 14 variables for SmMgTl. The PrMgTl, NdMgTl, GdMgTl, TbMgTl, and DyMgTl structures have been analyzed using the Rietveld technique. The REMgTl structures contain two cystallographically independent thallium sites, both with tri-capped trigonal prismatic coordination: Tl1Mg3RE6 and Tl2Mg6RE3. Together the magnesium and thallium atoms form three-dimensional [MgTl] networks with Mg-Mg distances of 327 and Mg-Tl distances in the range 299 - 303 pm (data for CeMgTl)
Syntheses And Characterization Of Mixed-Ligands Lead(Ii) Complexes, [Pb(bpy)(CH3COO)X] (X = I–, NO3 –, and ClO4 –), Crystal Structure Of [Pb(bpy)(NO3)(CH3COO)]N (A New 1-D Polymeric Compound)
Authors: Morsali Ali , Mahjoub Ali R. , Soltanian Mohammad J. , Pour Parisa E.
Published: August 2018

Lead(II) complexes with 2,2′-bipyridine (bpy) containing two different anions, [Pb(bpy)(CH3- COO)X] (X = I-, NO3
-, and ClO4
-), have been synthesized and characterized by CHN elemental analysis, IR-, 1H NMR- and 13C NMR spectroscopy. The structure of [Pb(bpy)(ClO4)(CH3COO)]n was confirmed by X-ray crystallography. The complex is a one-dimensional polymer as a result of perchlorate ligand bridging. The Pb atom has an unsymmetrical eight-coordinate geometry. The arrangement of the bpy, acetate and nitrate ligands leaves a coordination gap at the Pb(II) ion, occupied probably by a stereo-active lone pair of electrons. There is a π- π stacking interaction between the parallel aromatic rings that may be formed by influence lone pair activity
Alp Inhibitors: Vanadyl(IV) Complexes Of Ferulic And Cinnamic Acid
Authors: Ferrer Evelina G. , Salinas María V. , Correa María J. , Vrdoljak Fernanda , Williams Patricia A. M.
Published: August 2018

Two new vanadyl(IV) carboxylate complexes have been obtained: Na2[VO(Fer)2(CH3OH)2] and Na2[VO(Cin)2(CH3O)2] and characterized by elemental analysis and UV-vis, diffuse reflectance and IR and Raman spectroscopies (FerH2 = ferulic acid, CinH= cinnamic acid). The thermal behavior was also investigated. The inhibitory effect on alkaline phosphatase activity was tested for the compounds and ferulic and cinnamic acids as well as for the vanadyl(IV) complex of quinic acid for comparison. The ferulic complex together with the free ligands exhibited the lowest inhibitory effect, while the VO/quinic and VO/cinnamic complexes showed an intermediate inhibition potential
Synthesis And Luminescence Of RhIII(phpy)2(S∪E) Complexes With phpy– = Deprotonated 2-Phenylpyridine And S∪E– = Diethyldithiocarbamate, 2-Pyridinethiolate And 2-Quinolinethiolate
Authors: Pawlowski Valeri , Kunkely Horst , Vogler Arnd
Published: August 2018

Complexes of the general composition RhIII(phpy)2(S∪E) with phpy− = 2-(2-pyridyl)phenyl and S∪E− = diethyldithiocarbamate, 2-pyridinethiolate and 2-quinolinethiolate were prepared and characterized. The complexes with S∪E− = diethyldithiocarbamate and 2-pyridinethiolate show a low-temperature luminescence which originates from a phpy ππ∗ intraligand triplet. For the complex with S∪E− = 2-quinolinethiolate (or thiooxinate) the lowest-energy excited state is of the quinolinethiolate intraligand type. This complex displays a fluorescence as well as a phosphorescence under ambient conditions
Syntheses and Characterization of Two New Mixed-Ligand Bismuth(III) Complexes, Crystal Structure of [Bi(phen)2(NO3)(NCS)2(MeOH)]
Authors: Morsali Ali
Published: August 2018

Complexes [Bi(phen)2(NO3)(NCS)2(MeOH)] and [Bi(phen)2(NO3)2(NCS)] have been synthesized and characterized by their IR spectra and elemental analyses. The structure of the [Bi(phen)2(NO3)(NCS)2(MeOH)] complex has been confirmed by X-ray crystallography. The Bi atoms are unsymmetrically eight-coordinated, N6O2. The arrangement of the ligands does not show a gap in the coordination geometry around the Bi(III) ion, indicating that its lone pair of electrons is not active. The thiocyanate ligands are coordinated to the bismuth atom via the nitrogen atom. There is π-π stacking interactions between the parallel aromatic rings belonging to adjacent chains
On the Solid Solutions Eu1–xPt2Inx, Gd1–xPt2Inx, and Tm1–xNi2Inx
Authors: Lukachuk Mar’yana , Kalychak Yaroslav M. , Nilges Tom , Pöttgen Rainer
Published: August 2018

The binary cubic Laves phases EuPt2, GdPt2, and TmNi2 form extended solid solutions Eu1−xPt2Inx, Gd1−xPt2Inx, and Tm1−xNi2Inx. Samples within these homogeneity ranges have been prepared from the elements by arc-melting on water-cooled copper chills or by induction melting in sealed tantalum tubes and subsequent annealing. The indides were characterized by X-ray powder and single crystal diffraction: MgCu2 type, Fd3̅m, a = 770.68(6) pm, wR2 = 0.0251, 67 F2 values, 6 variables for Eu0.94(3)Pt2In0.06(3), a = 769.16(6) pm, wR2 = 0.0244, 67 F2 values, 6 variables for Eu0.85(2)Pt2In0.15(2), a = 760.12(9) pm, wR2 = 0.0693, 65 F2 values, 6 variables for Gd0.79(5)Pt2In0.21(5), and MgCu4Sn type, F 4̅3m, a=700.27(6) pm, wR2=0.0368, BASF=0.13(2), 175 F2 values, 8 variables for TmNi4In. The platinum and nickel atoms build up three-dimensional networks of corner-sharing Pt4/2 and Ni4/2 tetrahedra. These networks leave larger voids of coordination number 16 that are filled with the rare earth (RE) and the indium atoms. While the thulium and indium atoms are ordered in TmNi4In, one observes mixed RE/In occupancies in Eu0.94(3)Pt2In0.06(3), Eu0.85(2)Pt2In0.15(2), and Gd0.79(5)Pt2In0.21(5)
trans-Bis(saccharinato)zinc and -cadmium Complexes with N-(2-Aminoethyl)piperazine: Synthesis, Crystal Structures and IR Spectra
Authors: Yilmaz Veysel T. , Guney Serkan , Harrison William T. A.
Published: August 2018

The reactions of N-(2-aminoethyl)piperazine (aeppz) with tetraaqua-bis(saccharinato)zinc(II) and -cadmium(II) in ethanol solution yield the new complexes trans-[Zn(sac)2(aeppz)2] (1), and trans- [Cd(sac)2(aeppz)2] (2) (sac = saccharinate), respectively. The complexes were characterized by elemental analyses, IR spectroscopy and X-ray crystallography. Both complexes 1 and 2 are mononuclear of Ci symmetry. The zinc(II) and cadmium(II) ions are coordinated by two neutral aeppz ligands and two sac anions in an elongated distorted octahedral environment. The aeppz ligand acts as a bidentate N, N’ donor through the central heterocyclic N atom and the N atom of the aminoethyl group, while the sac ligand is O-coordinated via the carbonyl O atom. The packing of the molecules in the crystals in both complexes is consolidated by arene π −π stacking interactions between the sac rings and by intermolecular hydrogen bonds involving the amine groups of aeppz and the sulfonyl oxygen atoms of the sac ligands
Facile Syntheses of Novel Acyclic Polycarboxylic Acids
Authors: Lutz Matthias , Pursiainen Jouni , Aksela Reijo
Published: August 2018

The synthesis of novel di- and tricarboxylic acids is described. Starting from diethanolamine, a series of N-substituted diethanol derivatives were prepared which were converted in the subsequent reaction step into the corresponding carboxylic acids by treatment with chloroacetic acid. N,N-bis[2- (carboxymethoxy)ethyl]glycine was obtained by N-alkylation of glycine ethylester with ethyl 2-(2- bromoethoxy)acetate