bluuebunny/crossref_metadata_2025 huggingface dataset:
Niruriflavone, a New Antioxidant Flavone Sulfonic Acid from Phyllanthus niruri
Authors: Than N. N. , Fotso S. , Poeggeler B. , Hardeland R. , Laatsch H.
Published: February 2015

A new flavone sulfonic acid 1 named niruriflavone was isolated from the 70% ethanolic extract of the whole plant of Phyllanthus niruri (Euphorbiaceae), together with 6,10,14-trimethyl-2- pentadecanone, hypophyllanthin, gallic acid, brevifolin carboxylic acid, methyl brevifolin carboxylate, isoquercetin, quercetin-3-O-β -D-glucopyranosyl(1→ 4)-α-rhamnopyranoside, corilagin, and isocorilagin, whose structures were determined by spectroscopic methods and comparison with published data. In an ABTS cation radical reduction assay, niruriflavone (1) exhibited potent radical scavenging properties. A biological test system based on bioluminescence of the dinoflagellate Lingulodinium polyedrum did not reveal any prooxidant properties of 1 at 50 μM.
Transformation of Lapachol to a Novel Naphthoquinone and Related Compounds
Authors: Jassbi Amir R. , Singh Pahup , Lamba Jyoti , Jain Sonakshi , Baldwin Ian T. , Tahara Satoshi
Published: February 2015

In boiling pyridine, lapachol (1) is transformed into novel asymmetric naphthoquinone derivative, quadrilone (2), and into dehydro-α-lapachone (3), and adenophyllone (4). Lapachol used in the present study was isolated from the heartwood of Heterophragma quadriloculare and found to be the most abundant naphthoquinone.
Synthetic Entry to Tricyclic and Tetracyclic Quinuclidine Derivatives by Cycloaddition and Ring Transformation
Authors: Hamama Wafaa S. , El-Magid Osama M. Abd , Zoorob Hanafi H.
Published: February 2015

The (Z)-2-arylidene-quinuclidines 5 - 8 were synthesized. Their reaction with aliphatic dibasic functional reagents in both basic and acidic conditions afforded the fused heterocycles 9, 10 and 11. However, the reaction of arylidene derivative 5 with an aromatic dibasic functional reagent gave benzimidazole 13 in lieu of the anticipated tetracyclic system, quinuclidino[3,2-e]benzo[b]-1,4-diazepine 12. Cycloadditions of 5 with different reagents gave the heterocyclic derivatives 17, 19, 22 and 23. Acid-catalyzed cyclization of 5 with excess resorcinol gave 24. Compounds 9a, 19 and 24 showed antibacterial activities.
Structure Refinement of AuSn2
Authors: Rodewald Ute Ch. , Hoffmann Rolf-Dieter , Wu Zhiyun , Pöttgen Rainer
Published: February 2015

Well-shaped single crystals of binary AuSn2 were obtained as a side product during the synthesis of LiAu3Sn4. The structure of AuSn2 has been studied by X-ray diffractometer data: Pbca, Z = 8, a = 689.8(1), b = 701.1(1), c = 1177.3(2) pm, wR2 = 0.0533, 1234 F2 values, and 29 variables. The gold atoms show a distorted octahedral coordination by tin at Au-Sn distances ranging from 272 to 283 pm. The structure can be considered as an intergrowth of pyrite and marcasite related slabs. Consequently one observes Sn1-Sn2 dumb-bells with a Sn-Sn distance of 289 pm, while all other Sn-Sn distances are larger than 322 pm.
An Acetylated Eudesmane Glucoside from Apodytes dimidiata Growing in Madagascar
Authors: Harinantenaina Liva , Mananjarasoa Emilienne , Yamasaki Kazuo
Published: February 2015

A new eudesmane glucoside has been isolated from the aerial part of Apodytes dimidiata, an Icacinaceous plant widely used in the Southern African countries for its molluscicidal activities. The structure of the new compound was determined by spectroscopic methods. The chemosystematics of the genus belonging to the family Icacinaceae is discussed.
La(OH)2I(H2O): Closing a Gap in Rare Earth Hydroxide Halide Structural Chemistry
Authors: Nilges Tom
Published: February 2015

UCl3 type La(OH)2I can be stabilized by additional water molecules during a hydrothermal synthesis from hydroiodic acid and lanthanum carbonate hydrate at 453 K to form La(OH)2I(H2O). The new rare earth (RE) hydroxide halide hydrate crystallizes monoclinically, space group C2/m with lattice parameters of a = 19.691(3), b = 4.136(1), c = 6.286(1) Å, β = 108.45(1)° and V = 485.6(2) Å3, wR2 = 0.0695, 648 F2 values and 32 variables. La centered, distorted, tricapped, trigonal prisms formed by iodide, (OH−)- and (H2O) groups are connected via common edges in [001]-direction and common faces in [010]-direction to built up a zigzag like layered arrangement. Hydrogen bonding between the water molecules and iodide ions of adjacent La(OH)2I layers stabilize the UCl3 related structure, which was only observed for the lighter homologues La(OH)2X (X = Cl, Br) so far. DTA/TG and IR measurements substantiated the occurrence of (H2O)- and (OH−)-groups and semiquantitative EDX analyses proved a 1:1 composition for La:I in La(OH)2I(H2O).
The Squaric Acid Derivatives C8O4S2 and C8O4Se2 – Crystal Structures, Explosive Thermal Behavior and the Preparation of Carbon Suboxide Selenide OC3Se by Flash Vacuum Pyrolysis
Authors: Beck Johannes , Krieger-Beck Petra , Kelm Klemens
Published: February 2015

2,7-Diselenatricyclo[6.2.0.03.6]deca-1,3-diene-4,5,9,10-tetraone, C8O4Se2, was prepared from 1,2-diselenosquarate and squaric acid dichloride. Its crystal structure and the structure of the already known sulfur analogue C8O4S2 were determined (C8O4S2: orthorhombic, Pca21, a = 1413.64(2), b = 599.850(9), c = 968.8(1) pm; C8O4Se2: orthorhombic, Pnnm, a = 415.46(2), b = 894.29(5), c = 1160.14(7) pm). The structures are not isotypic and show a different packing of the molecules whose symmetry deviate only slightly from D2h. In the four-membered C4 rings the C-C bonds represent one single bond, one double bond and two slightly shortened single bonds. The C4 rings are thus to be considered as cyclobutene-dione fragments. The vigorous exothermic decomposition of the compounds that occurs on heating to 220 to 240 °C shows that both are energetic materials. The explosions are accompanied by a heat evolution of −192 kJ/mol for C8O4S2 and −224 kJ/mol for C8O4Se2. Performing the decomposition of C8O4S2 in a closed autoclave leaves a residue of the composition “C6S” which was examined by transmission electron microscopy techniques and shown to consist mainly of amorphous carbon. This thermal behaviour is limiting the utilization of C8O4S2 and C8O4Se2 as precursors for the syntheses of OC3S and the yet unknown OC3Se via FVP. The formation of OC3S could be proven by the reaction of the trapped, slightly yellow product (evaporation at 200 °C, pyrolysis at 500 °C, trapping at −196 °C) with aniline which yielded thiomalonic acid dianilide, of which the crystal structure was determined (monoclinic, C2/c, a = 2814.8(16), b = 1201.7(8), c = 809.2(4) pm, β = 91.88(4)°, V = 2736(3) ・ 106 pm3). The mass spectrum of C8O4Se2 shows the strongest signal for OC3Se+, and FVP experiments (evaporation at 220 °C, pyrolysis at 650 °C, trapping at −75 °C) yielded small amounts of a bright yellow material which rapidly converted into a black polymer.
Lanthanide Complexes with D-Penicillamine Methyl Ester: Formation Constants, Spectral and Thermal Properties
Authors: Sallam Shehab A. , Mahmoud Marwa A.
Published: February 2015

The complex-formation of the lanthanide(III) cations with D-penicillamine methyl ester have been investigated in acidic and neutral media. The macroscopic protonation constants of the ligand and the formation constants of [Ln·Pme]2+, [Ln·(Pme)2]+, [Ln·Pme·OH]+ and [Ln·Pme·(OH)2] complexes have been determined from pH-metric data using BEST computer program. Species distribution diagrams of the complexes were obtained and plotted using SPE and SPEPLOT computer programs. Elemental analyses of the solid complexes indicate the formation of 1:1 metal:ligand species. Infrared spectra show that coordination takes place through the NH2, the SH and the C=O groups of the ligand. The complexes decompose in four steps as shown by their TG and DTA analysis with the formation of Ln2(SO4)3 as a final product. Activation energy values (ΔEa) are correlated with the atomic radii of the metal ions. The mechanism of the thermal decomposition is proposed.
Synthesis, Crystal Structure, Spectral and Thermal Characterization of cis-Diaquabis(1,10-phenanthroline)zinc(II) Diorotate Hydrate, cis-[Zn(H2O)2(phen)2](H2Or)2 · (H2O)2.125
Authors: Yeşilel Okan Zafer , Uçar İbrahim , Bulut Ahmet , Ölmez Halis , Büyükgüngör Orhan
Published: February 2015

Preparation, X-ray crystal structure, thermal behavior, and IR spectroscopic studies of cis-diaquabis(1,10-phenanthroline)zinc(II) diorotate hydrate are described. In the compound [Zn(H2O)2(C12H8N2)2](C5H3N2O4)2·(H2O)2.125 (1), the zinc ion, located on a twofold axis, is coordinated by two aqua ligands together with a pair of bidentate 1,10-phenanthroline (phen) molecules, and exhibits a distorted octahedral coordination. The orotate anions have a single negative charge each. The metal−coordinated water molecules link the orotate ions to the metal complex via O-H· · ·O hydrogen bonds. Also the uncoordinated water molecules are bonded to orotate ions through O-H· · ·O hydrogen bonds. Thus, an extensive network of hydrogen bonds together with π-π, and π-ring interactions stabilize the crystal structure and form an infinitive three dimensional structure. The thermal decomposition pathway of 1 has been investigated by the help of thermal analysis data (TG, DTG and DTA).
Synthesis, Spectral, Thermal and Structural Characterization of the Copper(II) Saccharinato Complex of 2–Aminopyrimidine, [Cu(sac–O)2(ampym–N)2(H2O)2]·2ampym
Authors: Yeşilel Okan Zafer , Ölmez Halis , Paşaoğlu Hümeyra , Kaştaş Gökhan , Büyükgüngör Orhan
Published: February 2015

Bis(2-aminopyrimidine-N)diaquabis(saccharinato-O)copper(II) di(2-aminopyrimidine), [Cu(sac-O)2(ampym-N)2(H2O)2] · 2ampym was synthesized and characterized by means of elemental analysis, IR and UV-vis spectroscopy, magnetic susceptibility, simultaneous TG, DTG, DTA techniques, and X-ray diffraction. The complex crystallizes in the monoclinic space group P21/c [a = 7.4697(5), b = 10.1679(5), c = 22.743(2)Å , β = 92.844(5), Z = 2, R = 0.0275, wR= 0.0757, V = 1725.26(19) Å3]. The copper atom is bonded to two ampym N atoms and two sac O atoms as well as to two water O atoms in trans positions in the geometry of a distorted octahedron. There are also two ampym moieties as solvate molecules in the unit cell. The crystal structure is stabilized by N-H· · ·O, O-H· · ·N and C-H· · ·O type hydrogen bonding interactions. Intermolecular π−π interactions between the phenyl rings of ampym groups and C-H· · ·π interactions also support the packing of the molecules. The thermal decomposition of the complex has been studied.
Improved Synthesis of 2-(4-Propylphenyl)ethanol
Authors: Hashmi A. Stephen K. , Burkert Tobias , Bats Jan W. , Martyniak Aleksandra
Published: February 2015

A new procedure for the synthesis of 2-(4-propylphenyl)ethanol is provided. This new procedure significantly reduces side-products as 1-(4-propylphenyl)ethanol and 2-bromoethanol, which are obtained when using the previously known procedure. Only with the new procedure an efficient purification on the large scale needed for avoided-level-crossing muon-spin resonance experiments was possible.

Structural details of the title compound could be derived from an X-ray structure analysis of a crystalline derivative, the nitrobenzoyl ester.
Synthesis and Characterization of Silver(I) Saccharinate Complexes with Pyrazole and Imidazole Ligands: [Ag(sac)(pz)(H2O)]n and [Ag(sac)(im)] · 2H2O
Authors: Yilmaz Veysel T. , Hamamci Sevim , Büyükgüngör Orhan
Published: February 2015

Two new silver(I) saccharinate (sac) complexes, [Ag(sac)(pz)(H2O)]n (1) and [Ag(sac)(im)]·2H2O (2) (pz = pyrazole and im = imidazole), have been prepared and characterized by elemental analysis, IR spectroscopy, thermal analysis and single crystal X-ray diffraction. Complexes 1 and 2 crystallize in the monoclinic space group P21/c and triclinic space group P1̅, respectively. The sac, pz and im ligands all are N-coordinated. In 1, the [Ag(sac)(pz)] units are bridged by aqua ligands to generate a one-dimensional helical chain, in which the silver(I) ions exhibit a distorted square-planar AgN2O2 coordination geometry. The polymeric chains are connected by N-H· · ·O hydrogen bonds into sheets, which are further linked by aromatic π(pz) · · ·π(sac) stacking interactions into a three-dimensional supramolecular network. Complex 2 consists of individual molecules containing linearly coordinated silver(I) ions with a slightly distorted coordination of AgN2. The molecules interact with each other through hydrogen bonds and π· · ·π interactions to form a three-dimensional supramolecular network.
Synthesis and Structure of 1-Substituted Benzopyrano- [4’,3’-c]benzo[3”,4”-ƒ]-2,8-dioxabicyclo[3.3.1]nonane
Authors: Manolov Ilia , Maichle-Moessmer Caecilia , Niquet Elke
Published: February 2015

The base catalyzed condensation reaction between 4-hydroxycoumarin and 3-acetylcoumarin (3-benzoylcoumarin) in water at reflux led to the formation of 1-methyl (1-phenyl)- benzopyrano[4’,3’-c]-benzo[3”,4”-ƒ ]-2,8-dioxabicyclo[3.3.1]nonane (2a, b) as final products. When 4-hydroxycoumarin and 3-acetylcoumarin reacted in a glacial acetic acid in the presence of potassium acetate the final product was 7-[3-acetyl-2-oxo-3,4-dihydro-2H-[1]benzopyran-4-yl]methyl- 6H,14H,14bH-bis-([1]benzopyrano)[4,3-b:4’,3’-d]pyran-6,14-dione (4). 4-Hydroxycoumarin and 4-(5-bromo-2-hydroxyphenyl)-3-buten-2-one were condensed in water at reflux and 1- methylcoumarino-[4’,3’-c]-bromobenzo[3”,4”-ƒ ]-2,8-dioxabicyclo[3.3.1]nonane was a final product (3).
Synthesis, Semiempirical, Stereoselectivity and Pharmacological Activity of a New Class of Spiro Pyrrolidine and Isoquinoline Derivatives
Authors: Londhe A.V. , Gupta B. , Kohli S. , Pardasani P. , Pardasani R. T.
Published: February 2015

1,3-Dipolar cycloaddition of azomethine ylides derived from acenaphthylene-1,2-dione and 5- methyl-benzo[b]-thiophene-2,3-dione with L-proline, thiazolidine-4-carboxylic acid and 1,2,3,4- tetrahydroisoquinoline-3-carboxylic acid with various electron deficient dipolarophiles leads to the formation of novel spiroheterocycles having two or more chiral centers. Semiempirical studies have been performed to understand the stereochemical course of the reaction. The synthesized cycloadducts have been screened for antimicrobial and toxicological activity.
Structure of the Cocrystal of 2,2’-Diamino-4,4’-bis(1,3-thiazole) and 4,4’-Bipyridine
Authors: Amiri Maryam G. , Ranjbar Zohreh R. , Morsali Ali , Xiao Hong-Ping
Published: February 2015

A new cocrystal based upon 2,2’-diamino-4,4’-bis(1,3-thiazole) and 4,4’-bipyridine has been synthesized and characterized. Self-assembly of this compound in the solid state is likely caused by both hydrogen boding and π-π stacking, and the network contains large vacant voids.
1,1- and 1,2-Allylboration of Alkyn-1-ylsilanes Bearing Si-H Functions. Electron-Deficient Si-H-B Bridges, and Intramolecular Hydrosilylation
Authors: Wrackmeyer Bernd , Tok Oleg L.
Published: February 2015

The reactions of n-hexyn-1-ylsilanes or arylethyn-1-ylsilanes, bearing methyl groups and one (2), two (3) or three hydride functions (4) at the silicon atom, with triallylborane 1 lead primarily to products of 1,1- or 1,2-allylboration. In the alkenes (5, 9, 13) formed by stereoselective 1,1-allylboration, with the silyl and the diallylboryl groups in cis-positions at the C=C bond an electron-deficient Si-H-B bridge is present. The activation of the Si-H bond in these alkenes induces intramolecular hydrosilylation under very mild reaction conditions to give 1,4-silabora-cyclohept-2-enes (7 and 11). The products of 1,2-allylboration (6, 10, 14) are further transformed into 1-boracyclohex-2-enes (8, 12, 15) and 7-borabicyclo[3.3.1]non-2-enes (16, 17) by intramolecular 1,2-allylboration reactions. The proposed structures are based on consistent sets of 1H, 11B, 13C and 29Si NMR data.
Redox Behaviour of Pyrazolyl-Substituted 1,4-Dihydroxyarenes: Formation of the Corresponding Semiquinones, Quinhydrones and Quinones
Authors: Lerner Hans-Wolfram , Margraf Günter , Kretz Tonia , Schiemann Olav , Bats Jan W. , Dürner Gerd , Biani Fabrizia Fabrizi de , Zanello Piero , Boltea Michael , Wagner Matthias
Published: February 2015

Pyrazolyl-substituted 1,4-dihydroxybenzene and 1,4-dihydroxynaphthene derivatives have been synthesized by reaction of 1,4-benzoquinone and 1,4-naphthoquinone, respectively, with pyrazole. Cyclovoltammetric measurements have shown that 1,4-benzoquinone possesses the potential to oxidize 2-(pyrazol-1-yl)- and 2,5-bis(pyrazol-1-yl)-1,4-dihydroxybenzene. The 2,5-bis(pyrazol-1-yl)- 1,4-dihydroxybenzene reacts with air to give quantitatively black insoluble 2,5-bis(pyrazol-1-yl)-1,4- quinhydrone. Black crystals of 2,5-bis(pyrazol-1-yl)-1,4-quinhydrone suitable for X-ray diffraction were grown from methanol at ambient temperature (monoclinic C2/c). The poor yields of pyrazolylsubstituted 1,4-dihydroxybenzene and 1,4-dihydroxynaphthene derivatives can be explained by the formation of insoluble black quinhydrons in the reaction of benzoquinone and naphthoquinone with pyrazole. The dianions of 2-(pyrazol-1-yl)- and 2,5-bis(pyrazol-1-yl)-1,4-dihydroxybenzene react with oxygen to give the corresponding semiquinone anions. 2,5-Bis(pyrazol-1-yl)-1,4-benzoquinone shows two reversible one-electron reduction processes in cyclovoltammetric measurements, whereas pyrazolyl-substituted 1,4-dihdroxybenzene and -naphthene derivatives undergo irreversibile electrontransfer processes.
Dimethylaminomethylene-α-D-xylo-hept-5-ulofuranurononitrile as Building Block in the Synthesis of ‘Reversed’ C-Nucleoside Analogues
Authors: Hashmi Imran Ali , Feist Holger , Michalik Manfred , Reinke Helmut , Peseke Klaus
Published: February 2015

3-O-Benzyl-6-deoxy-1,2-O-isopropylidene-6-(dimethylaminomethylene)-α-D-xylo-hept-5-ulofuranurononitrile (1) was reacted with amidinium salts, S-methylisothiouronium sulfate, and guanidinium chloride, respectively, in the presence of bases to furnish the 4-(3-O-benzyl-1,2-O-isopropylidene- α-D-xylo-tetrofuranos-4-yl)pyrimidine-5-carbonitriles 2 and the 4-(1,2-O-isopropylidene- α-D-glycero-tetr-3-enofuranos-4-yl)pyrimidine-5-carbonitriles 3, respectively. Treatment of 1 with ethyl 5-aminopyrazole-4-carboxylates yielded the ethyl 7-(3-O-benzyl-1,2-O-isopropylidene- α-D-xylo-tetrofuranos-4-yl)-6-cyanopyrazolo[1,5-a]pyrimidine-3-carboxylates 4 and the ethyl 7-amino-6-(3-O-benzyl-1,2-O-isopropylidene-α-D-xylo-pentofuranuronoyl)pyrazolo[1,5-a]pyrimidine- 3-carboxylates 5, respectively. Reaction of 1 with 2-benzimidazolylacetonitrile in the presence of sodium methanolate afforded 1-amino-2-(3-O-benzyl-1,2-O-isopropylidene-α-D-xylo-pentofuranuronoyl) benzo[4,5]imidazo[1,2-a]pyridine-4-carbonitrile (6) and 1-amino-2-(3-deoxy-1,2-O-isopropylidene- α-D-glycero-pent-3-enofuranuronoyl)benzo[4,5]imidazo[1,2-a]pyridine-4-carbonitrile (7).
Oxetanes from Photocycloaddition of 2-Aminopropenenitriles to Methyl Phenylglyoxylate and Benzils
Authors: Wolven Christiane van , Döpp Dietrich , Henkel Gerald
Published: February 2015

By irradiation of methyl phenylglyoxylate (1) in benzene solution in presence of equimolar amounts of 2-aminopropenenitriles H2C=C(NR2)CN (3a - e, NR2 = morpholino, 1-pyrrolidinyl, 1-piperidinyl, hexamethyleneimino, heptamethyleneimino) the corresponding 2R∗,3R∗ head-to-head oxetanes 4a - e were obtained in moderate yields (11 - 52%) along with 2 - 28% of rac-dimethyl 2,3- diphenyltartrate (2). In presence of (S)-2-(2-methoxymethylpiperidin-1-yl)propenenitrile ((+)-3g) 1 is transformed into 26% of 2 and 33% of a mixture of diastereomeric oxetanes 4g,4’g in a ratio of 1.4 : 1 which could be improved to 2.5 : 1 by preparative layer chromatography. The absolute configuration of the major diastereomer 4g was unambiguously confirmed by a single crystal X-ray structure determination to be 2R,3R,2’S. Analogous photoadditions to benzil (5a), 4,4’-bis-(trifluoromethyl)benzil (5b) and 4,4’-dichlorobenzil (5c) with (+)-3g and its lower homologue (S)-2-(2-methoxymethylpyrrolidin- 1-yl)propenenitrile ((-)-3f) gave oxetanes only in low yield as detected by 1H NMR. Byproducts arise from competitive symmetrical α-cleavage of 5.
Oxokohlenstoffe und verwandte Verbindungen, 30 [1]. Über die Umsetzung von Quadratsäure mit Pyrazolinonen / Oxocarbons and Related Compounds, 30 [1]. On the Reaction of Squaric Acid with Pyrazolinones
Authors: Schmidt Arthur H. , Schreck Timo , Rötz Ralf , Freytag-Loringhoven Sarah von
Published: February 2015

Heating of squaric acid (1) with the 1-aryl-3-methyl-5-oxo-2,5-dihydro-1H-pyrazoles 3a - j and the 1,3-disubstituted pyrazolinones 7a - d in the molar ratio of 1:2 in a mixture of n-BuOH/toluene afforded the bis(pyrazolyl)-squaraines 4a - j and 8a - d, respectively. Reaction of an excess of 1 with the pyrazolinone 3j yielded 4j and the 3-hydroxy-4-pyrazolyl-cyclobutene-1,2-dione 6 as a byproduct. In contrast to disubstituted pyrazolinones, the trisubstituted pyrazolinones 9a - e reacted with squaric acid (1) to give the hydroxy-oxopyrazolyl-cyclobutenediones 10a - e.
Prefluostatin and New Urauchimycin Derivatives Produced by Streptomycete Isolates
Authors: Yao C. B. Fondja , Schiebel M. , Helmke E. , Anke H. , Laatsch H.
Published: February 2015

Guided by chemical screening, two new members of the antimycin group, urauchimycin C (1b) and D (1a), were isolated from the marine-derived Streptomyces sp. isolate B1751 and from a terrestrial strain AdM21, together with prefluostatin (2), a new natural derivative of isoprekinamycin (4). Their structures were established on the basis of NMR data and by comparison with known compounds. In the agar diffusion test, urauchimycin C (1b) and D (1a) were antibiotically inactive against some bacteria and fungi at a concentration of 25 μg per paper disk, while the isoprekinamycin derivative 2 showed weak cytotoxicity and moderate activity in the agar diffusion test against Bacillus subtilis, Mucor miehei, Escherichia coli and Staphylococcus aureus at concentrations of 20 μg per paper disk.
Aromatization of Hantzsch 1,4-Dihydropyridines with Urea-Hydrogen Peroxide/Maleic Anhydride
Authors: Momeni Ahmad R. , Aliyan Hamid , Mombeini Heidar , Massah Ahmad R. , Naghash Hamid J.
Published: February 2015

A simple method for the oxidative aromatization of Hantzsch 1,4-dihydropyridines to the corresponding pyridines is reported using urea-hydrogen peroxide/maleic anhydride in acetonitrile.
Synthesis, Characterization and Antibacterial Studies of Some 1,2,4-Triazole Derivatives Containing a 6-Chloropyridin-3-yl methyl Moiety
Authors: Holla Bantwala S. , Prasanna Channamata S. , Poojary Boja , Ashok Mithun , Rao Kottapalli S. , Shridhara Kanakamajalu
Published: February 2015

5-(6-Chloropyridin-3-yl methyl)-4-phenyl-1,2,4-triazole-3-thiol (2) and 5-substituted-4-phenyl- 1,2,4-triazole-3-thiols (3) were synthesized. Alkylation and aminomethylation reactions of these triazoles were also carried out. Some of the newly synthesized compounds were screened for their antibacterial activities.
Crystal Structure of NdNiO3 at 123 and 292 K
Authors: Alonso José A. , Demazeau Gérard , Largeteau Alain , Kurowski Daniel , Hoffmann Rolf-Dieter , Pöttgen Rainer
Published: February 2015

Well-shaped, small single crystals of the NdNiO3 perovskite were grown under high oxygen pressure conditions in a belt-type press at 4 GPa. The reaction took place in sealed platinum capsules in the presence of KClO3 as oxidizing agent. It seems that the choice of hydroxides of the involved cations as precursor reagents is crucial for the success of the crystal growth, via water vapor transport reactions. NdNiO3 was investigated by X-ray powder and single crystal diffraction at 123 and 292 K: GdFeO3 type, Pbnm, a = 538.10(7), b = 537.91(7), c = 760.26(10) pm, wR2 = 0.0434, 338 F2 values, and 29 variables at 292 K. The lowtemperature data gave no hint for a monoclinic distortion: Pbnm, a = 537.91(8), b = 538.49(8), c = 760.02(12) pm, wR2=0.0299, 338 F2 values, and 29 variables. At room temperature, the Ni-O distances vary from 193.9 to 194.2 pm, and the O-Ni-O angles cover the range from 89.5 to 90.5°. Similar small distortions are observed for the NiO6 octahedra at 123 K. Due to the strong orthorhombic distortion, the neodymium atoms have only nine oxygen neighbors at Nd-O distances from 236.0 to 295.7 pm.
Physical, Chemical, and Technological Property Correlation with Chemical Structure: The Potential of QSPR
Authors: Katritzky Alan R. , Dobchev Dimitar A. , Karelson Mati
Published: February 2015

Correlations of simple and complex physical, and chemical, biological and technological properties with chemical structure are reviewed. When an adequate training set of structures and experimentally determined property values are available, the equations produced enable the prediction of these properties of molecules as yet synthesized or indeed as yet unknown. Frequently they also offer considerable insights into the manner in which the structure controls the property. Many further applications of this methodology can be anticipated
Synthesis and Transformations of Ethyl 3-Formyl-1H-indole-2-carboxylate. Preparation of Aplysinopsin and β-Carboline Thiohydantoin Analogues
Authors: Jakše Renata , Bevk David , Golobič Amalija , Svete Jurij , Stanovnik Branko
Published: February 2015

Various aplysinopsin and β -carboline thiohydantoin analogues were prepared starting from ethyl 3-formyl-1H-indole-2-carboxylate by condensation with the active methylene group of 2-thiohydantoin, rhodanine, or thiobarbituric acid derivatives
Synthesis of 5-Methoxy-4-benzyloxazoles from Tyrosine and m-Tyrosine under Bischler-Napieralski Conditions
Authors: Tussetschläger Stefan , Baro Angelika , Laschat Sabine
Published: February 2015

Various 2-substituted 5-methoxy-4-benzyloxazoles 6 and 9 were obtained from tyrosine and m-tyrosine derived amides 5 and 8 by treatment with phosphoryl chloride. A mechanism is proposed in order to explain the observed steric effects of the substituents in 2-position
Syntheses and Properties of Cycloamidines Based on 4H-Imidazoles
Authors: Beckert Rainer , Hippius Catharina , Gebauer Tillmann , Stöckner Frances , Lüdigk Christina , Weiß Dieter , Raabe Dietrich , Günther Wolfgang , Görls Helmar
Published: February 2015

Employing three different syntheses a broad spectrum of 4H-imidazoles 3a - 3s has been synthesized. In the course of the two-fold aminolysis reaction leading to derivatives 3q - 3s, deeply colored byproducts could be isolated and structural characterized.These novel donor-acceptor derivatives of type 7 consist of an 1H- and 4H-imidazole which are connected by a nitrogen bridge and rearrange via rapid 1,3-/1,5-hydride shifts. Using 1H NMR experiments the aminolysis product 3p shows prototropic isomers which could be detected in equilibrium for the first time. Cyclovoltammetric measurements of a series of substituted 2-aryl derivatives 3d - 3i displayed two reversible single electron transfer steps with relatively small semiquinone formation constants between 102 and 4×103. The 4H-imidazole 3d was successfully converted into boratetraaza-pentalene 8a, which showed two well separated reduction potentials. The value of semiquinone formation constant of 8a (1.8×1015) is even higher than those reported for similar derivatives. 4H-imidazoles can also be employed for the efficient complexation of catalytically important metals as exemplified by copper complexes 11 and 12. Derivative 3m, which possesses an additional chelating pyridine substructure, formed a stable complex of structural composition Zn(3m)2 with diethyl zinc
Bromocyclization of Unsaturated Oximes. Synthesis of Five-Membered Cyclic Nitrones (Pyrroline N-Oxides)
Authors: Gulla Mahendra , Bierer Lars , Schmidt Stefan , Redcliffe Leo , Jäger Volker
Published: February 2015

The cyclization of a ribose-derived pentenose oxime with various halogen electrophiles showed bromine to be the most effective reagent, leading to 80% of L-lyxo/D-ribo-pyrroline N-oxides in an 84:16 diastereomeric ratio. In order to explore the scope of this facile process, several other γ,δ - unsaturated oximes were submitted to this reaction. Depending on the substitution pattern, 23 - 87%, yields of pyrroline N-oxides of were registered. With α-allyl-β -ketoester oximes the alkoxycarbonyl group proved a similar (ethoxy) or even better (t-butoxy) trapping nucleophile, leading preferentially to the corresponding bromolactone oxime. - With 2,2-dimethyl-3-butene aldoxime, the corresponding 3-bromopyrroline N-oxide was formed, due to a formal, unusual N-endo cyclization to the chain terminus. This was exploited for a new access to six-membered nitrones from a γ,δ -pentene aldoxime, with addition of Br/OH to the C=C of the 4-pentenal first, and oximation/cyclization following then
The Solid Solution CeAuIn1–xMgx – Structure, Magnetic Properties and Specific Heat Data
Authors: Rayaprol Sudhindra , Heying Birgit , Pöttgen Rainer
Published: February 2015

Four different samples of the solid solution CeAuIn1−xMgx with x = 0.2, 0.4, 0.6, and 0.8 have been prepared from the elements in sealed tantalum tubes in an induction furnace. The samples were characterized through X-ray powder and single crystal data: ZrNiAl type, P6̅2m, Z = 3, a = 774.54(7), c = 420.32(10) pm, wR2 = 0.0203, 395 F2 values, 15 variables for CeAuIn0.871Mg0.129, a = 775.25(7), c = 419.36(10) pm, wR2 = 0.0488, BASF = 0.10(1), 397 F2 values, 16 variables for CeAuIn0.640Mg0.360, a = 774.62(7), c = 420.13(10) pm, wR2 = 0.0435, 376 F2 values, 15 variables for CeAuIn0.445Mg0.555, a = 773.80(11), c = 420.82(8) pm, wR2 = 0.0415, 392 F2 values, 15 variables for CeAuIn0.228Mg0.772. The lattice parameters show no pronounced changes within the solid solution. The largest shift occurs for the x parameter of the mixed occupied In/Mg positions. Due to the difference in size, the trigonal prisms around the Au1 atoms at the origin become smaller with an increasing content of magnesium. The In/Mg-In/Mg distances decrease from 334.5 (CeAuIn0.871Mg0.129) to 328.3 (CeAuIn0.228Mg0.772) pm, and consequently one observes also shorter bonds to the Au1 atoms with an increasing content of magnesium concentration. Susceptibility measurements reveal trivalent cerium for all CeAuIn1−xMgx compounds, with no evidence sign of magnetic ordering down to 2 K. The disorder created by chemical substitution destroys the longrange magnetic ordering which can be attributed to the triggering of non Fermi-liquid (NFL) like behavior.
Synthese und Charakterisierung der Lanthanoidbleioxidnitrate LnPbO2NO3 mit Ln = La, Pr, Nd und Sm/ Synthesis and Characterisation of Lanthanide Lead Oxide Nitrates LnPbO2NO3 with Ln = La, Pr, Nd, and Sm
Authors: Dill Simone , Kawamoto Yoriko , Grigoraviciute Inga , Kareiva Aivaras , Meyer Hans-Jürgen
Published: February 2015

The lanthanide lead oxide nitrates LnPbO2NO3 with Ln = La, Pr, Nd, and Sm were synthesised by solid state reactions of the nitrates in air and subsequent reactions in sealed silica tubes under in situ generated NOx atmosphere. The crystal structure of LaPbO2NO3 was refined isotypically with BiPbO2NO3 in the tetragonal space group I4/mmm by means of Rietveld powder XRD. According to this refinement, an orientational disorder is present for the NO3
− ions. The homologous LnPbO2NO3 compounds were indexed isotypically for Ln = Pr, Nd, and Sm, and their lattice parameters were refined. The structures contain [LnPbO2]+ layers, alternating with single [NO3]− layers. Thermal analyses (DTA/TG) were performed for LnPbO2NO3 compounds and magnetic measurements for NdPbO2NO3. The employment of LaPbO2NO3 as a precursor for oxide materials, or as an NOx storage material is considered.
Synthesis and Structures of Cycloalkanetellurium(IV) Fluorides and Azides
Authors: Klapötke Thomas M. , Krumm Burkhard , Mayer Peter , Scherr Matthias
Published: February 2015

Telluracycloalkanes were fluorinated with XeF2 and the resulting tellurium(IV) fluorides were reacted with (CH3)3SiN3 to obtain the corresponding tellurium(IV) azides. The products, (CH2)5TeF2, (CH2)4TeF2, (CH2)5Te(N3)2 and (CH2)4Te(N3)2, were characterized by spectroscopic methods. The molecular structure of (CH2)4TeF2 as well as the structure of an oxygen bridged species, [(CH2)5TeN3]2O, have been determined by X-ray diffraction.
Synthesis and Characterization of Cadmium and Mercury Saccharinate Complexes with 2-Dimethylaminoethanol: cis-[Cd(sac)2(dmea)2] and [Hg(sac)2(dmea)(H2O)]
Authors: Yilmaz Veysel T. , Kars Vecdi , Kazak Canan
Published: February 2015

The new cadmium and mercury saccharinate (sac) complexes, cis-[Cd(sac)2(dmea)2] (1) and [Hg(sac)2(dmea)(H2O)] (2) (dmea = 2-dimethylaminoethanol), have been prepared and characterized by elemental analysis, IR spectroscopy, thermal analysis and single crystal X-ray diffraction. In complex 1, the cadmium(II) ion is coordinated by two neutral dmea ligands and two sac anions in a distorted octahedral CdN3O3 coordination geometry. The dmea ligand acts as a bidentate N, O chelate, while the sac ligands behave as an ambidentate ligands. One of them coordinates to the cadmium(II) ion through the carbonyl oxygen atom, while the other is N-bonded. In complex 2, the mercury(II) ion is coordinated by an aqua ligand, a chelating dmea ligand and two N-bonded sac ligands, forming a distorted trigonal bipyramidal coordination HgN3O2. The molecules interact with each other through O-H···O hydrogen bonds and aromatic π(sac)···π(sac) stacking interactions, leading to a three-dimensional supramolecular network.
An Amperometric Acetone Sensor by Using an Electro-Deposited Pb-Modified Electrode
Authors: Wang Chia-Chi , Weng Yu-Ching , Chou Tse-Chuan
Published: February 2015

An amperometric acetone sensor was developed by using an electrodeposited Pb electrode in a sodium tartrate electrolyte. The major factors determining the electrode and sensing characteristics such as the applied potential, electrodeposition current density, electrodeposition temperature, agitation rate, and sensing temperature were explored. The best conditions for preparation of the electrodeposited Pb electrode were obtained at a 30 mA cm−2 electrodeposition current density and a 30 °C electrodeposition temperature. Additionally, the optimal sensing conditions are a 155 rpm agitation rate and 50 °C sensing temperature with the applied potential in the range from −2.25 ~−2.35 V (vs. Ag/AgCl). The results also revealed that the electrodeposited Pb electrode has a good linearity between the response current and the acetone concentration. This type of acetone sensor has excellent selectivity and shows the highest sensitivity at 8 μAppm−1cm−2.
Synthesis of Pentalene Systems Employing a Sequence of Pauson-Khand Reaction, Michael Reaction, and Desilylation
Authors: Becheanu Armand , Bell Thomas , Laschat Sabine , Baro Angelika , Frey Wolfgang , Steinke Nelli , Fischer Peter
Published: February 2015

The utility of cyclopentadiene (4) in intermolecular Pauson-Khand reactions was investigated. Subsequently, a 1,4-addition of lithium organocuprates was carried out followed by desilylation. This synthetic concept allows the preparation of β -functionalized bicyclo[3.3.0]octane derivatives 1a - c in only three steps in total yields up to 53%.
Influence of a Nitro Side Group on Liquid Crystalline Properties of Trimellitimides
Authors: Orzeszko Andrzej
Published: February 2015

Two series of ester imides from trimellitic anhydride as well as 6-nitrotrimellitic anhydride (4-carboxy-6-nitrophthalic anhydride) have been synthesized. Their thermotropic properties have been compared. Only one nitro compound, N-dodecyl-4-[(4’-decyloxybiphenyl-4-yl)oxycarbonyl]- 6-nitrophthalimide has shown liquid crystalline properties.
Two New Glycosides from Sanicula lamelligera
Authors: Zhou Ling-Yun , Liu Hai-Yang , Xie Bai-Bo , Liu Zhi-Hai , Chen Chang-Xiang
Published: February 2015

Two new glycosides, 21-O-β -D-glucopyranosyl-olean-12-ene-3β , 16α, 21β , 22α, 28-pentol-3-O- β -D-glucopyranosyl (1→2)-[β -D-arabinopyranosyl (1→3)]-β -D-glucopyranoside (1) and 4-O-β - D-glucopyranosyl rosmarinic acid (3), along with the known compound rosmarinic acid (2) were isolated from the whole plants of Sanicula lamelligera Hance. Their structures were elucidated by spectroscopic analysis and chemical means.
Two New Phenolic Glycosides from Rhizomes of Curculigo crassifolia
Authors: Li Ning , Chen Ji-Jun , Zhou Jun
Published: February 2015

Curculigo crassifolia (Bak.) Hook. f. (Hypoxidaceae) is a tall perennial herb used as a folk medicine to treat child pneumonia by local people in Yunnan Province. Two new phenolic glycosides named crassifoside C (1) and crassifoside D (2) were isolated from the ethanolic extract of rhizomes of Curculigo crassifolia, and their structures were identified by 2D-NMR spectroscopic techniques and chemical transformations. In addition, seven known compounds (3 - 9) were isolated and identified by spectroscopic analysis and comparison of their spectral data with those reported previously.
Xyloccensins X1 and X2, Two New Mexicanolides from the Fruit of a Chinese Mangrove Xylocarpus granatum
Authors: Cheng Fan , Zhou Yuan , Wu Jun , Zou Kun
Published: February 2015

Two new mexicanolides, named xyloccensins X1 and X2 (1 - 2), were isolated from the fruit of the Chinese mangrove Xylocarpus granatum. Their structures were elucidated on the basis of spectroscopical data, especially 2D NMR techniques including HSQC, HMBC, and NOESY.
Crotasteroiridocin: A New Steroiridoid from Crotalaria emarginella and its anti-Inflammatory Activity
Authors: Ahmed Bahar , Al-Howiriny Tawfeq A. , Mossa Jaber S.
Published: February 2015

The aerial parts of Crotalaria emarginella Vatke (Leguminosae) have afforded a new steroidiridoid, characterized as 1’-hydroxy-isoiridomyrmecinyl- 1’-O-β -3-O-α-stigmast-5-ene, designated as crotasteroiridocin (1), which shows a unique combination of iridoid and sterol units, found very rarely in nature. Furthermore, a rare iridoid glucoside namely, bis-desoxy-dihydro-monotropein (2) has also been isolated from the aerial parts of the plant. The structures of the isolated products were elucidated on the basis of spectral and chemical studies. The anti-inflammatory activity has also been screened, wherein compounds 1 and 2 have shown 25.92% and 28.39% activity respectively, with respect to phenyl butazone against carrageenan employing the rat paw method.
Lanthanoidhaltige Komplexe monovakanter Keggin- und Dawson-Polyoxoanionen / Novel Lanthanide Complexes of Monovacant Keggin- and Dawson-Type Polyoxoanions
Authors: Drewes Daniel , Krebs Bernt
Published: February 2015

The new polyoxotungstates Cs6nK2n[{(Pr(H2O)7)(Pr(H2O)2)(α-SiW11O39)}4]n ・ 33nH2O (1), (NH4)14[{Tb(H2O)3(α2-P2W17O61)}2] ・ 39H2O (2) and (NH4)7.33K2.67Ho1.33[{Ho(H2O)3(α2- P2W17O61)}2] ・45H2O (3) were synthesized in aqueous solution and characterized by IR and Raman spectroscopy, 31P NMR spectroscopy (for 2 and 3), energy dispersive X-ray fluorescence analysis and single-crystal X-ray analysis. 1 exhibits a novel one-dimensional chain-like structure which is built up from of monovacant (α-SiW11O39)8− Keggin-type anions linked by Pr(III) atoms. Half of the Pr(III) atoms are eight-coordinate (square antiprism), with four sites occupied by one anion, three by water molecules, and the eighth site by a terminal oxygen atom of a second anion. The other Pr(III) atoms are coordinated by seven water molecules and two terminal oxygen atoms of two Keggin moieties. The dimeric [{Ln(H2O)3(α2-P2W17O61)}2]14− anions in 2 (Ln = Tb) and 3 (Ln = Ho) consist of two (α2-P2W17O61)10− Dawson-type anions linked by two trivalent lanthanides. The lanthanides exhibit a square-antiprismatic coordination sphere which is built up by three water molecules, four terminal oxygen atoms of one Dawson-anion and one oxygen atom of the second Dawson-anion. The crystal structures of the new compounds are compared with known species and the influence of the Ln(III) ionic radii is discussed
Fluorite-Type Solid Solutions in the System Y-Ta-O-N: A Nitrogen-Rich Analogue to Yttria-Stabilized Zirconia (YSZ)
Authors: Schilling H. , Wolff H. , Dronskowski R. , Lerch M.
Published: February 2015

Fluorite-type phases in the system Y-Ta-O-N have been prepared by ammonolysis of Y-Ta-O precursors. X-ray powder patterns show unusual asymmetrical reflection profiles explained by DFT and MD methods. The anion vacancy concentration of some of these oxynitrides is similar to that of yttria-doped zirconia, commercially used as solid electrolyte in fuel cells. Hence, these compounds are interesting candidates for mixed oxygen-nitrogen superion conductors
Kristallstrukturen mit Bausteinen des CaBe2Ge2-Typs – Die Verbindungen Sm2Pt6P3 und Ca2Pd3Sb4 / Crystal Structures with CaBe2Ge2-Type Units – The Compounds Sm2Pt6P3 and Ca2Pd3Sb4
Authors: Imre Anette , Johrendt Dirk , Mewis Albrecht
Published: February 2015

Single crystals of Sm2Pt6P3 (a = 4.095(1), c = 45.313(9) Å ) were prepared by heating the elements in a melt of NaCl/KCl at 1100°C. The compound crystallizes with a new tetragonal type of structure (I41/amd; Z = 4) consisting of units which correspond to the CaBe2Ge2 type except for one significant difference: In the layer of PPt4 tetrahedra only two of four P positions are occupied. Therefore this layer is built up by corner- instead of edge-sharing PPt4 tetrahedra. Four of these units are stacked along [001]. Single crystals of Ca2Pd3Sb4 (a = 4.506(1), c = 41.538(8) Å ) were obtained by reaction of the elements at 900°C. The crystal structure (I4/mmm; Z = 4) consists of two blocks. The first one has the composition CaPd2Sb3 and can be derived from the CaBe2Ge2 type. In the second one (formula CaPdSb) the atoms are arranged analogous to the CeMg2Si2 type. Both blocks alternate along [001]
Synthesis, Crystal Structure and Magnetic Behaviour of Dimeric and Polymeric Gadolinium Trifluoroacetate Complexes
Authors: John Daniela , Rohde Alexander , Urland Werner
Published: February 2015

The gadolinium(III) trifluoroacetates ((CH3)2NH2)[Gd(CF3COO)4] (1), ((CH3)3NH)[Gd(CF3 COO)4(H2O)] (2), Gd(CF3COO)3(H2O)3 (3) as well as Gd2(CF3COO)6(H2O)2(phen)3 · C2H5OH (4) (phen = 1,10-phenanthroline) were synthesized and structurally characterized by X-ray crystallography. These compounds crystallize in the space group P1̅ (No. 2, Z = 2) (1, 2 and 4) and P 21/c (No. 14, Z = 4) (3), respectively, with the following lattice constants 1: a = 884.9(2), b = 1024.9(2), c = 1173.1(2) pm, α = 105.77(2), β = 99.51(2), γ = 107.93(2)°; 2: a = 965.1(1), b = 1028.6(1), c = 1271.3(2) pm, α = 111.83(2), β = 111.33(2), γ = 90.44(2)°; 3: a = 919.6(2), b = 1890.6(4), c = 978.7(2) pm, β = 113.94(2)°; 4: a = 1286.7(8), b = 1639.3(8), c = 1712.2(9) pm, α = 62.57(6), β = 84.13(5), γ = 68.28(5)°. The compounds consist of Gd3+ ions which are bridged by carboxylate groups either to chains (1 and 2) or to dimers (3 and 4). In addition to the Gd3+ dimers, compound (4) also contains monomeric Gd3+ units. The magnetic behaviour of 2 and 3 was investigated in a temperature range of 1.77 to 300 K. The magnetic data for these compounds indicate weak antiferromagnetic interactions
(C6N2H18)Sb4S7 a Thioantimonate(III) with a Layered [Sb4S7]2– Anion in the Presence of a Diprotonated Amine as Structure Director
Authors: Spetzler Volker , Näther Christian , Bensch Wolfgang
Published: February 2015

The new thioantimonate(III) (C6N2H18)Sb4S7 (C6N2H16 = 1,6-diaminohexane) was synthesized under solvothermal conditions using Sb, S and 1,6-diaminohexane (1,6-DAH). The compound crystallizes as orange needles in the triclinic space group P1̅ with lattice parameters a = 6.9834(5), b = 11.8748(10), c = 13.6588(12) Å , α = 115.248(9), β = 100.165(9) and γ = 92.568(9)°. A central SbS4 group shares edges with two other SbS4 moieties forming Sb3S8 units which are joined by SbS3 pyramids sharing vertices to form a chain of alternating Sb3S8 and SbS3 units. One S atom of the SbS3 pyramid connects neighboring chains into sheets which contain large Sb10S10 heterorings. The sheets are then further connected into four atoms thick double sheets. Six edge-linked SbS4 units are condensed yielding a complex Sb6S14 building block. Layers of diprotonated amines and thioantimonate( III) layers are stacked along [001] in a sandwich-like fashion with an interlayer distance of 8.46 Å . The amine layer is two molecules thick with the amines being oriented parallel to the anionic layers. The title compound represents the first example for a layered [Sb4S7]2− anion with a diamine as structure director. The compound is an optical semiconductor with a band-gap of about 1.9 eV
Konkurrierende Liganden: Theophyllin als nicht- und stark koordinierender Ligand in Quecksilber(II)-Komplexen / Competing Ligands: Theophylline as Non- and Strongly Coordinating Ligand in Mercury(II) Complexes
Authors: Nolte Matthias , Pantenburg Ingo , Meyer Gerd
Published: February 2015

[{Hg(CF3)2}(ThpH)(H2O)](H2O) (1), [{Hg4(Thp)4}(ClO4)4(H2O)8](H2O)4 (2), [{Hg(ThpH)2} (NO3)](NO3) (3) and {Hg(Thp)Cl}(H2O) (4) (ThpH = theophylline, C7H8N4O2) have been synthesized by slow evaporation of aqueous solutions of the mercuric salts Hg(CF3)2, Hg(ClO4)2, Hg(NO3)2, or HgCl2 and theophylline. Their crystal structures were determined on the basis of single crystal X-ray data. The coordination polymers 1 and 2 crystallize with triclinic symmetry, P1̅ (no. 2), with a = 468.8(2), b = 1256.4(5), c = 1445.5(6) pm, α = 67.15(3), β = 89.21(3), γ = 89.40(3)° and a = 833.6(1), b = 1862.7(2), c = 2182.9(2) pm, α = 111.61(1), β = 90.98(1), γ = 95.51(1)°, respectively. 3 and 4 crystallize with monoclinic symmetry, Pc (no. 7), a =1194.1(1), b=1258.8(2), c=735.5(2) pm, β =96.96(2)° and P21/n (no. 14), a=1069.0(2), b =911.6(1), c=1089.9(2) pm and β = 96.87(2)°. In 1 the theophylline molecules are non-coordinating to mercury and leave the Hg(CF3)2 molecule unchanged. Only weak electrostatic attractions to one keto-oxygen atom of theophylline and one water molecule hold this co-crystallisate together. In 2, the theophyllinate anion, Thp−, strongly coordinates with both N(7) and N(9) to HgII forming a large ring with eight Hg atoms that incorporates the water molecules. One sort of nitrate ions in 3 is weakly attached to HgII with the theophylline molecules still bound strongly through N(9). The chloride ligand and the theophyllinate ion seem to have the same strengths as ligands in 4 as they are both attached to HgII with the shortest distances possible
New Compounds RE(Zn,Al)8 and Yb4Zn20.3Al12.7 and their Crystal Structures
Authors: Stel’makhovych Ol’ga , Kuz’ma Yurij
Published: February 2015

The crystal structures of several new compounds have been determined using X-ray analysis. The intermetallic compound HoZn5Al3 (a = 8.586(3), c = 16.538(5) Å , RF = 0.0413, RW = 0.0521) has its own structure type (space group I4/mmm), which has been found for the first time. The following compounds are isostructural with the previous one: YZn5.52Al2.48 (a = 8.6183(1), c = 16.5048(3) Å , RI = 0.078, RP = 0.116), DyZn4.96Al3.04 (a = 8.5887(1), c = 16.5002(3) Å , RI = 0.077, RP = 0.114), ErZn5.37Al2.63 (a = 8.5525(2), c =16.3997(5) Å , RI = 0.081, RP = 0.111), TmZn5.64Al2.36 (a = 8.70429(8), c = 16.3943(4) Å , RI = 0.088, RP = 0.095), LuZn5.58Al2.42 (a = 8.5616(1), c= 16.3052(3) Å , RI =0.081, RP =0.101). The intermetallic compound Yb4Zn20.3Al12.7 (a = 8.6183(1), c = 16.5048(3) Å , RI = 0.085, RP = 0.112) adopts the Yb8Cu17Al49 - type structure (space group I4/mmm). The relationship between the HoZn5Al3-type and the Yb8Cu17Al49-type structures is discussed.